Forecast Discussions mentioning any of "ACARS" "MDCRS" "AIRCRAFT" "TAMDAR" "AMDAR" "WVSS" received at GSD on 05/28/16

Area Forecast Discussion
National Weather Service Columbia SC
239 PM EDT FRI MAY 27 2016

.SYNOPSIS...
High pressure will remain over the forecast area through tonight.
Moisture will increase Saturday through Sunday associated with
low pressure nearing the Southeast coast.

&&

.NEAR TERM /THROUGH TONIGHT/...
Cumulus continue developing across the Midlands and CSRA with a
mid level cap suppressing any showers development. Clouds will
dissipate with sunset and loss of heating with mostly clear skies
expected through the early morning hours. System in the Atlantic
will continue slowly moving toward the coast overnight with
moisture and clouds ahead of the system reaching the coast around
daybreak. As such expect some increasing clouds across the area
during the early morning hours...however no showers are
anticipated overnight. Low temperatures tonight will be in the
lower 60s.

&&

.SHORT TERM /SATURDAY THROUGH MONDAY NIGHT/...
The NHC is monitoring the area of low pressure in the western
Atlantic, and future forecasts will be based more on their
guidance if the system develops sub-tropical or tropical
characteristics.

Models showing moisture increasing from the east through the day
Saturday as an area of low pressure in the eastern Atlantic
progresses westward towards the South Carolina Coast. The models
are coming into a somewhat better agreement with the track and
movement of the area of low pressure through the period. General
consensus seems to bring the low towards the coast, moving inland
somewhere north of Charleston, then slowing the low as it moves
into eastern South Carolina. Models then trend towards moving the
low northeastward as we move into Monday.

For Saturday, expecting the morning to remain mainly dry across
the cwa, then increasing shower and thunderstorm chances across
the east during the afternoon. Rain/thunderstorm chances continue
Sunday into Monday as the low slowly moves through the region.
Highest chances for precip will remain greatest across the eastern
counties, with pops trending lower the further west you go. Trended
towards the WPC qpf amounts through the period. With the potential
slow movement to the low, can not rule out periods of heavy
rainfall which could produce localized flooding.

Used the guidance consensus for the temperature forecast.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
Much uncertainty in the longer term forecast period. Models
differ on the upper air solutions through the middle of the week,
with the gfs showing a weak ridge north of the cwa and a weak low
just east. The ecmwf shows a trough east of the area, and high
pressure over the region. All in all, can not rule out any
isolated or scattered afternoon showers and thunderstorms any day
next week. Temperature forecast was a general blend of guidance,
which is generally at or above normal through the period.

&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
VFR conditions to dominate the taf period...with early morning
mvfr fog possible at AGS/OGB.

Satellite imagery shows some cumulus have formed across the taf
sites with the system in the Atlantic slowly moving west
northwestward. expect cumulus to linger through the afternoon and
evening hours then dissipate with sunset. Moisture will continue
slowly increasing overnight with additional moisture arriving
Saturday morning as winds turn northeasterly. Showers associated
with the Atlantic system will move into the taf sites on Saturday
reaching OGB around midday and the remainder of the sites just
after the end of the period. As such have included VCSH for OGB
near the end of the period with no mention elsewhere. Winds will
be light and variable overnight then become northeasterly at 8
knots or less from 14z onward.

EXTENDED AVIATION OUTLOOK...Restrictions probable in showers and
thunderstorms Saturday through Monday as a system moves into the
area from the Atlantic Basin.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...None.

&&

$$



  [top] Area Forecast Discussion National Weather Service Charleston SC 159 PM EDT FRI MAY 27 2016 .SYNOPSIS... Atlantic high pressure will prevail today. A wave of low pressure will develop over the southwest Atlantic and approach the Southeast coast Saturday and Sunday. The low could affect the area into early next week before eventually lifting northeast. && .NEAR TERM /THROUGH TONIGHT/... Today: deep layered dry air and subsidence will maintain mostly sunny skies with highs in the mid to upper 80s. Few to scattered cumulus will likely develop along the sea breeze and quickly push inland this afternoon given the prevailing onshore flow. Tonight...Mainly clear skies this evening will give way to an increase in clouds along and east of I-95 later tonight. Deeper moisture ahead of an advancing inverted trough and surface low pres north of the Bahamas will be approaching the Carolina Coast. Model timing and low level convergence patterns remain consistent and we maintained a slight chance of showers late tonight with chance pops along upper Charleston County nearing daybreak. Given the advancing cloud shield late...some lows may be reached earlier in the overnight with rising temps along coastal areas late. && .SHORT TERM /SATURDAY THROUGH MONDAY/... The forecast through the short term period remains quite complex and uncertain as it is dependent on the evolution of developing low pressure over the western Atlantic. An area of low pressure will be located around 250-300 miles off coastal SC/GA Saturday morning. The strength and classification of the low is still uncertain, however the latest National Hurricane Center outlook indicates that the low has a high likelihood of becoming a tropical or sub-tropical system within 48 hours. A reconnaissance AIRCRAFT is scheduled to investigate the system Friday afternoon. Models are in fairly good agreement that the low will track northwest towards the SC coast Saturday into Saturday night. Thereafter, model solutions diverge. Consensus takes the low into Charleston county sometime Sunday afternoon. Regardless of whether or not this system is classified as tropical, the primary hazard of interest at this time is potential heavy rain. Should persistent heavy rain affect coastal areas coincident with high tide, the threat for localized flooding will be enhanced. Currently, the SC coast looks to have the biggest threat for heavy rain/localized flooding. Of course, a shift in forecast track could result in a different scenario. Continued uncertainty into Monday as the low could meander over the area or in the vicinity. GFS and NAM keep the low spinning in the vicinity for a couple days, while the Euro is more progressive and has it lifting northeast pretty quickly, similar to it`s run 24 hours ago. Overall, the weather will be fairly unsettled given the deep-layered moisture in place and the low pressure system in the vicinity. The forecast features at least chance POPs through the period, highest on Sunday. Needless to say, significant adjustments will likely be needed with future forecast packages when details are better defined. && .LONG TERM /MONDAY NIGHT THROUGH THURSDAY/... Forecast for the work week continues to be quite uncertain as it remains highly dependent on the evolution of a low pressure system that will impact the Southeast. A couple models are more progressive in lifting the low northeast away from the area quickly leaving a rather benign weather pattern mid week, while others want to keep it spinning in the vicinity before eventually dissipating. Have maintained rain chances in the forecast through the period. && .AVIATION /18Z FRIDAY THROUGH WEDNESDAY/... VFR at KCHS/KSAV through 12Z Sat though there is a small chance for MVFR ceilings at KCHS around daybreak Sat. Increasing chances for showers moving into the KCHS terminal during the day Sat but the best chances will be after 18Z when the Atlantic low moves closer to the coast. EXTENDED AVIATION OUTLOOK...Chances for at least periodic flight restrictions this weekend into early next week as a low pressure system approaches from the southeast. && .MARINE... Low pressure northeast of the Bahamas and sprawling high pressure from Bermuda to the mid-Atlantic states will maintain onshore flow through tonight. Slowly backing wind directions will range ENE to E 10 kt or less this morning, increasing to near 15 kt tonight. Seas will be on a slow uptick with 2 ft heights building to 3 to 4 ft tonight. Saturday through Wednesday: The marine forecast remains low confidence as it is highly dependent on evolution of a low pressure system over the Western Atlantic. On Saturday, pressure gradient will tighten as an area of low pressure lifts northeast towards the area and potentially develops into a tropical or sub-tropical system. This will result in northeast winds increasing to 15-20 knots. Thereafter, models differ greatly on the strength and track of the low, but general consensus takes the low into Charleston county Sunday afternoon. Then, it could either lift northeast or remain spinning in the vicinity through early next week. Given this uncertainty, significant changes should be expected in future forecast packages. Rip Currents: An increased risk of rip currents for the upcoming holiday weekend appears likely as onshore flow and swell energy increases in advance of an approaching low pressure system. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...None. SC...None. MARINE...None. && $$ SYNOPSIS... NEAR TERM...JRL SHORT TERM...ECT LONG TERM...ECT AVIATION...ECT/JRL MARINE...ECT Area Forecast Discussion National Weather Service Columbia SC 139 AM EDT SAT MAY 28 2016 .SYNOPSIS... High pressure will remain over the forecast area through tonight. Newly formed tropical depression two is forecast to become tropical storm Bonnie on Saturday and push into the coastal plain early Sunday. Chances of rain will increase over the weekend with potential for locally heavy rainfall. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... Moisture will begin increasing in advance of the approaching tropical depression two, with increasing mid to high level cloudiness expected. && .SHORT TERM /6 AM THIS MORNING THROUGH MONDAY NIGHT/... Tropical depression two will be steady moving northwestward approaching the coast on Saturday while a plume of deep tropical moisture moves inland over the forecast area with precipitable water values pushing well over 1.5 inches. Expecting Saturday morning to remain mainly dry across the cwa, then increasing shower and thunderstorm chances across the east during the afternoon. Rain/thunderstorm chances continue Sunday into Monday as the low slowly moves through the region. Highest chances for precip will remain greatest across the eastern counties, with pops trending lower the further west you go. Trended towards the WPC qpf amounts through the period due to wide spread in the forecast qpf guidance. With the potential slow movement to the low, can not rule out periods of heavy rainfall which could produce localized flooding. Used the guidance consensus for the temperature forecast. && .LONG TERM /TUESDAY THROUGH FRIDAY/... Much uncertainty in the longer term forecast period. Models differ on the upper air solutions through the middle of the week, with the gfs showing a weak ridge north of the cwa and a weak low just east. The ecmwf shows a trough east of the area, and high pressure over the region. All in all, can not rule out any isolated or scattered afternoon showers and thunderstorms any day next week. Temperature forecast was a general blend of guidance, which is generally at or above normal through the period. && .AVIATION /06Z SATURDAY THROUGH WEDNESDAY/... VFR conditions expected today, with the possible exception of fog in the very near term at AGS. Main focus will be on tropical cyclone over the Atlantic progged to move NW towards the SC coast today and tonight, then slow down or become nearly stationary near the SC coast Sunday. Current satellite and surface obs indicate area of stratocumulus cloudiness, with CIGS above VFR level, near the coast drifting north. This would appear to preclude fog at OGB, and may impede fog at AGS later tonight, although appearance of clear skies at AGS in the very near term may allow some fog to form there. Latest array of high resolution models indicate shower activity ahead of the approaching cyclone could reach mainly the southern and eastern forecast area (FA) this afternoon, with some increasing chances of rain and associated lowering of CIGS tonight, again mainly CAE/CUB and OGB, with bulk of activity appearing to stay mainly east of AGS/DNL through tonight. EXTENDED AVIATION OUTLOOK...Restrictions probable in showers and possible thunderstorms Sunday and Sunday night, possibly lingering into Monday or longer, as a tropical system stalls or moves only slowly up the coast. && .CAE WATCHES/WARNINGS/ADVISORIES... GA...None. SC...None. && $$
Area Forecast Discussion National Weather Service Columbia SC 239 PM EDT FRI MAY 27 2016 .SYNOPSIS... High pressure will remain over the forecast area through tonight. Moisture will increase Saturday through Sunday associated with low pressure nearing the Southeast coast. && .NEAR TERM /THROUGH TONIGHT/... Cumulus continue developing across the Midlands and CSRA with a mid level cap suppressing any showers development. Clouds will dissipate with sunset and loss of heating with mostly clear skies expected through the early morning hours. System in the Atlantic will continue slowly moving toward the coast overnight with moisture and clouds ahead of the system reaching the coast around daybreak. As such expect some increasing clouds across the area during the early morning hours...however no showers are anticipated overnight. Low temperatures tonight will be in the lower 60s. && .SHORT TERM /SATURDAY THROUGH MONDAY NIGHT/... The NHC is monitoring the area of low pressure in the western Atlantic, and future forecasts will be based more on their guidance if the system develops sub-tropical or tropical characteristics. Models showing moisture increasing from the east through the day Saturday as an area of low pressure in the eastern Atlantic progresses westward towards the South Carolina Coast. The models are coming into a somewhat better agreement with the track and movement of the area of low pressure through the period. General consensus seems to bring the low towards the coast, moving inland somewhere north of Charleston, then slowing the low as it moves into eastern South Carolina. Models then trend towards moving the low northeastward as we move into Monday. For Saturday, expecting the morning to remain mainly dry across the cwa, then increasing shower and thunderstorm chances across the east during the afternoon. Rain/thunderstorm chances continue Sunday into Monday as the low slowly moves through the region. Highest chances for precip will remain greatest across the eastern counties, with pops trending lower the further west you go. Trended towards the WPC qpf amounts through the period. With the potential slow movement to the low, can not rule out periods of heavy rainfall which could produce localized flooding. Used the guidance consensus for the temperature forecast. && .LONG TERM /TUESDAY THROUGH FRIDAY/... Much uncertainty in the longer term forecast period. Models differ on the upper air solutions through the middle of the week, with the gfs showing a weak ridge north of the cwa and a weak low just east. The ecmwf shows a trough east of the area, and high pressure over the region. All in all, can not rule out any isolated or scattered afternoon showers and thunderstorms any day next week. Temperature forecast was a general blend of guidance, which is generally at or above normal through the period. && .AVIATION /18Z FRIDAY THROUGH WEDNESDAY/... VFR conditions to dominate the taf period...with early morning mvfr fog possible at AGS/OGB. Satellite imagery shows some cumulus have formed across the taf sites with the system in the Atlantic slowly moving west northwestward. expect cumulus to linger through the afternoon and evening hours then dissipate with sunset. Moisture will continue slowly increasing overnight with additional moisture arriving Saturday morning as winds turn northeasterly. Showers associated with the Atlantic system will move into the taf sites on Saturday reaching OGB around midday and the remainder of the sites just after the end of the period. As such have included VCSH for OGB near the end of the period with no mention elsewhere. Winds will be light and variable overnight then become northeasterly at 8 knots or less from 14z onward. EXTENDED AVIATION OUTLOOK...Restrictions probable in showers and thunderstorms Saturday through Monday as a system moves into the area from the Atlantic Basin. && .CAE WATCHES/WARNINGS/ADVISORIES... GA...None. SC...None. && $$
  [top] Area Forecast Discussion National Weather Service Charleston SC 159 PM EDT FRI MAY 27 2016 .SYNOPSIS... Atlantic high pressure will prevail today. A wave of low pressure will develop over the southwest Atlantic and approach the Southeast coast Saturday and Sunday. The low could affect the area into early next week before eventually lifting northeast. && .NEAR TERM /THROUGH TONIGHT/... Today: deep layered dry air and subsidence will maintain mostly sunny skies with highs in the mid to upper 80s. Few to scattered cumulus will likely develop along the sea breeze and quickly push inland this afternoon given the prevailing onshore flow. Tonight...Mainly clear skies this evening will give way to an increase in clouds along and east of I-95 later tonight. Deeper moisture ahead of an advancing inverted trough and surface low pres north of the Bahamas will be approaching the Carolina Coast. Model timing and low level convergence patterns remain consistent and we maintained a slight chance of showers late tonight with chance pops along upper Charleston County nearing daybreak. Given the advancing cloud shield late...some lows may be reached earlier in the overnight with rising temps along coastal areas late. && .SHORT TERM /SATURDAY THROUGH MONDAY/... The forecast through the short term period remains quite complex and uncertain as it is dependent on the evolution of developing low pressure over the western Atlantic. An area of low pressure will be located around 250-300 miles off coastal SC/GA Saturday morning. The strength and classification of the low is still uncertain, however the latest National Hurricane Center outlook indicates that the low has a high likelihood of becoming a tropical or sub-tropical system within 48 hours. A reconnaissance AIRCRAFT is scheduled to investigate the system Friday afternoon. Models are in fairly good agreement that the low will track northwest towards the SC coast Saturday into Saturday night. Thereafter, model solutions diverge. Consensus takes the low into Charleston county sometime Sunday afternoon. Regardless of whether or not this system is classified as tropical, the primary hazard of interest at this time is potential heavy rain. Should persistent heavy rain affect coastal areas coincident with high tide, the threat for localized flooding will be enhanced. Currently, the SC coast looks to have the biggest threat for heavy rain/localized flooding. Of course, a shift in forecast track could result in a different scenario. Continued uncertainty into Monday as the low could meander over the area or in the vicinity. GFS and NAM keep the low spinning in the vicinity for a couple days, while the Euro is more progressive and has it lifting northeast pretty quickly, similar to it`s run 24 hours ago. Overall, the weather will be fairly unsettled given the deep-layered moisture in place and the low pressure system in the vicinity. The forecast features at least chance POPs through the period, highest on Sunday. Needless to say, significant adjustments will likely be needed with future forecast packages when details are better defined. && .LONG TERM /MONDAY NIGHT THROUGH THURSDAY/... Forecast for the work week continues to be quite uncertain as it remains highly dependent on the evolution of a low pressure system that will impact the Southeast. A couple models are more progressive in lifting the low northeast away from the area quickly leaving a rather benign weather pattern mid week, while others want to keep it spinning in the vicinity before eventually dissipating. Have maintained rain chances in the forecast through the period. && .AVIATION /18Z FRIDAY THROUGH WEDNESDAY/... VFR at KCHS/KSAV through 12Z Sat though there is a small chance for MVFR ceilings at KCHS around daybreak Sat. Increasing chances for showers moving into the KCHS terminal during the day Sat but the best chances will be after 18Z when the Atlantic low moves closer to the coast. EXTENDED AVIATION OUTLOOK...Chances for at least periodic flight restrictions this weekend into early next week as a low pressure system approaches from the southeast. && .MARINE... Low pressure northeast of the Bahamas and sprawling high pressure from Bermuda to the mid-Atlantic states will maintain onshore flow through tonight. Slowly backing wind directions will range ENE to E 10 kt or less this morning, increasing to near 15 kt tonight. Seas will be on a slow uptick with 2 ft heights building to 3 to 4 ft tonight. Saturday through Wednesday: The marine forecast remains low confidence as it is highly dependent on evolution of a low pressure system over the Western Atlantic. On Saturday, pressure gradient will tighten as an area of low pressure lifts northeast towards the area and potentially develops into a tropical or sub-tropical system. This will result in northeast winds increasing to 15-20 knots. Thereafter, models differ greatly on the strength and track of the low, but general consensus takes the low into Charleston county Sunday afternoon. Then, it could either lift northeast or remain spinning in the vicinity through early next week. Given this uncertainty, significant changes should be expected in future forecast packages. Rip Currents: An increased risk of rip currents for the upcoming holiday weekend appears likely as onshore flow and swell energy increases in advance of an approaching low pressure system. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...None. SC...None. MARINE...None. && $$ SYNOPSIS... NEAR TERM...JRL SHORT TERM...ECT LONG TERM...ECT AVIATION...ECT/JRL MARINE...ECT Area Forecast Discussion National Weather Service Charleston SC 732 AM EDT SAT MAY 28 2016 .SYNOPSIS... Tropical Depression Two over the southwest Atlantic will approach the South Carolina coast through tonight, before moving onshore over Sunday before weakening. The low could linger in the vicinity into early next week before eventually lifting away to the northeast. A cold front will approach the region late next week. && .NEAR TERM /THROUGH TONIGHT/... Today: Tropical Storm Warnings remain in effect for the South Carolina Coastal areas. This ahead of the early season tropical system expected to remain a depression for much of the day prior to reaching the Gulf Stream tonight. Deep moisture will continue to advect into the Coastal Carolinas today with bands of showers expected to increase in coverage across Eastern South Carolina; especially during the afternoon hours from Beaufort northward. Widespread clouds will hold temps down into the lower 80s across northern zones. Across inland Georgia, only some high clouds to start the day and models indicate a fair amount of destabilization by the afternoon. we maintain a slight chance of showers and tstms to the west of I-95 this afternoon as convection will tend to be more diurnal bound on a decent 850 MB theta-e ridge across our inland Georgia Zones. It will become breezy along coastal areas this afternoon as the sea breeze develops along with various mesoscale shower bands. Tonight...The tropical low will reach the Gulf Stream waters and just about all of the model guidance indicates that any strengthening should be modest as upper level wind shear atop the system is forecast to remain rather substantial. Pops will be categorical across across much of the Charleston Tri-County area as strong low level convergence and deep tropical moisture with pwats of 2 inches or better in place. Rain will likely be heavy at times with potential for tstms. Most of the rain will likely fall to the north of the Savannah River overnight. Winds ahead of the tropical system will ramp up along the coast with potential of tropical storm force winds in the warning area. && .SHORT TERM /SUNDAY THROUGH TUESDAY/... The forecast through the short term period continues to remain quite complex and still somewhat uncertain, highly dependent upon the evolution of Tropical Depression Two over the southwest Atlantic between Bermuda and the Bahamas. The official forecast from the National Hurricane Center continues to track a weakening tropical storm/depression along coastal Charleston County on Sunday Afternoon. Gusty winds associated with the low are expected to gradually subside as the low either stalls or hooks briefly before beginning to slide slowly to the northeast sunday night. the ECMWF had an interesting solution on the 00Z run with a good bit of upper forcing from a 45 kt upper jet streak enhancing heavy rain across the South Carolina forecast area on the western side of the surface low. The QPF differences between the models remain quite substantial and revolve not only on complex mesoscale details but on synoptic forcing and atop the system. We have bumped up QPF to 2-3 inches across the Charleston Tri-County but some higher amounts could fall back west into places like Hampton and Allendale Counties. Due to the small and likely compact nature to the system there will likely only be some occasional convective bands that contain thunder storms, so we are showing no more than chance t-storms through the period. If deep convection were to develop on a knot near the center, there could be small chances for rotation given 25-30 kt of deep layered shear but the window at this time appears too small to play any tornado risk across Eastern Charleston and Berkeley Counties.The risk for Tropical Storm force winds will be highest Tonight into early Sunday as the storm reaches the coast. the areas most likely to experience Tropical Storm winds with gusts up to 40 mph, will be immediate coastal South Carolina, including the Charleston metro. Winds of this magnitude may bring down a few trees and powerlines. Some power outages are possible. Model solutions still vary on the evolution of Tropical Depression Two into Tuesday, but consensus slowly lifts the weakening low northeast from north coastal South Carolina towards the North Carolina Outer Banks by Tuesday. Thus, the main window for any threats with this system will have ended. Assuming this track holds, precipitation chances should decrease through the day Monday as deepest moisture moves out of the area. Locations across southeast Georgia could very well be dry much of the day given the position relative to the low. Current forecast has PoPs ranging from 40-50% north to around 20% in the south. On Tuesday, rain chances revolve around the more typical summertime diurnal convection. High temperatures will be near normal in the mid 80s to around 90 (highest across southeast Georgia), with lows mainly in the upper 60s to around 70. && .LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/... Models are in fairly good agreement for the long term period. Weak pressure pattern will be in place for the latter half of the work week as whatever remnants of the tropical system remains meanders off the mid-Atlantic coast and eventually dissipates. A cold front is then forecast to approach the region Friday into Saturday, resulting in an increase in precipitation chances. Temperatures will be near to slightly above normal as heights aloft build. && .AVIATION /12Z SATURDAY THROUGH WEDNESDAY/... KCHS: VFR until later today. Could see cigs dropping to mvfr this afternoon or evening, as Tropical Depression 2 approaches. Showers associated with very out fringes of the system may develop in the vicinity by mid to late morning, but greater chances still appear to be in the late afternoon and evening hours. Diurnal enhancements including the sea breeze will result in some wind gusts near 20 kt this afternoon. Tonight rains will increase and become heavier, winds should become gusty as the gradient tightens but have not shown any gusts topping 20 kt as yet. KSAV: VFR conditions will likely persist. Deeper moisture is forecast to remain north of the terminal. There may be a few spotty light showers around the area this morning and again this afternoon into the overnight, but potential not enough to add any vchs or shra to the KSAV terminal forecast. EXTENDED AVIATION OUTLOOK...Chances for at least periodic flight restrictions into early next week, especially at KCHS, as the tropical system impacts coastal South Carolina. && .MARINE... Tropical Depression Two currently located around 265 miles southeast of Charleston this morning will track northwest towards the area today, and eventually move onshore somewhere in the vicinity of Charleston Sunday afternoon. Winds/seas will deteriorate as result, with tropical storm conditions expected over the nearshore SC waters (including the Charleston Harbor) and portions of the outer Georgia waters late tonight into Sunday, where Tropical Storm Warnings remain in effect. Some uncertainty still remains in the track of Tropical Depression Two, but consensus has the low meandering in the vicinity early Monday before slowly lifting to the northeast into Tuesday. Latest National Hurricane Center forecast indicates that the system will weaken as this occurs, so marine conditions are expected to steadily improve. Thereafter, winds/seas should remain below any headline criteria through late week. Rip Currents: A high risk of rip currents all beaches today and elevated risks into early next week. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...HIGH RISK FOR RIP CURRENTS through this evening for GAZ117-119- 139-141. SC...Tropical Storm Warning for SCZ045-047>052. HIGH RISK FOR RIP CURRENTS through this evening for SCZ048>051. MARINE...Tropical Storm Warning for AMZ330-350-352-374. && $$ SYNOPSIS... NEAR TERM... SHORT TERM...ECT LONG TERM...ECT AVIATION...ECT MARINE...ECT
  [top] Area Forecast Discussion...Updated for Aviation National Weather Service Peachtree City GA 735 AM EDT SAT MAY 28 2016 .SHORT TERM /Today through Sunday/... Tropical depression two will be moving northwestward toward the SC coast during the short term period. At this time...at least part of GA should be under the subsidence around the depression...however a few showers and thunderstorms approaching the east central zones are possible. So...have continued with slight chance pops for that area this afternoon and tonight. Also...the far northwest corner of the state may be affected by the increase in southerly moist flow into the central Gulf Coast area. a slight chance of convection still looks reasonable for the area north and west of Cedartown to Ellijay for this afternoon. Depending on the location of the depression on Sunday...it may be possible for showers or thunderstorms to circulate into GA. The westward extent of any precipitation is still questionable. For now...chance or slight chance pops have been included for much of the north and east central zones for Sunday. 41 && .LONG TERM /Sunday Night through Friday/... Models in better consensus with main influencing features of fcst period. The either tropical depression or storm approaching the SC coast should slowly turn north to NE late Sunday then hug the coastline placing it off the NC Outerbanks by late Wednesday. Weak subsidence west of this system should limit diurnally driven convection across the CWA into Monday then the chances gradually increase thru the week with greatest potential Wednesday thru Friday as we get a south to southwest fetch of deep gulf moisture and ramped up instability. Some discrepancies exist among guidance in the evolution of a weak 850-mb low translated from an amplifying upper trough into the southeast CONUS by Friday/Saturday. While this could serve to focus more organized or widespread storm development...the environment should be favorable of at least scattered coverage anyway with daytime heating. Above normal temps /AOA 3-7 degrees more than climo/ are on tap this week with Tuesday expected to be the warmest as progged highs in the upper 80s to low 90s should be reached for most areas. Better cloud coverage and storm potential after midweek should keep local temps moderated a bit more. Baker && .AVIATION... 12Z UPDATE... VFR to continue for this cycle. Few to scattered 050-060 mainly during the afternoon. Winds east to southeast 6 to 9kt after 14z. Only isolated convection mainly north and east of the taf sites today. //ATL CONFIDENCE...12Z UPDATE... High on all elements. 41 && .PRELIMINARY POINT TEMPS/POPS... Athens 86 64 86 66 / 10 20 30 10 Atlanta 86 66 87 69 / 5 10 20 5 Blairsville 82 60 82 62 / 10 20 30 10 Cartersville 87 62 88 65 / 20 10 20 5 Columbus 87 66 89 70 / 5 10 5 5 Gainesville 84 65 85 66 / 5 20 30 10 Macon 88 64 89 66 / 10 10 20 5 Rome 87 62 89 65 / 20 10 20 10 Peachtree City 86 61 87 65 / 5 10 20 5 Vidalia 86 67 87 70 / 20 20 20 5 && .FFC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...41 LONG TERM....Baker AVIATION...41
  [top] Area Forecast Discussion National Weather Service Columbia SC 139 AM EDT SAT MAY 28 2016 .SYNOPSIS... High pressure will remain over the forecast area through tonight. Newly formed tropical depression two is forecast to become tropical storm Bonnie on Saturday and push into the coastal plain early Sunday. Chances of rain will increase over the weekend with potential for locally heavy rainfall. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... Moisture will begin increasing in advance of the approaching tropical depression two, with increasing mid to high level cloudiness expected. && .SHORT TERM /6 AM THIS MORNING THROUGH MONDAY NIGHT/... Tropical depression two will be steady moving northwestward approaching the coast on Saturday while a plume of deep tropical moisture moves inland over the forecast area with precipitable water values pushing well over 1.5 inches. Expecting Saturday morning to remain mainly dry across the cwa, then increasing shower and thunderstorm chances across the east during the afternoon. Rain/thunderstorm chances continue Sunday into Monday as the low slowly moves through the region. Highest chances for precip will remain greatest across the eastern counties, with pops trending lower the further west you go. Trended towards the WPC qpf amounts through the period due to wide spread in the forecast qpf guidance. With the potential slow movement to the low, can not rule out periods of heavy rainfall which could produce localized flooding. Used the guidance consensus for the temperature forecast. && .LONG TERM /TUESDAY THROUGH FRIDAY/... Much uncertainty in the longer term forecast period. Models differ on the upper air solutions through the middle of the week, with the gfs showing a weak ridge north of the cwa and a weak low just east. The ecmwf shows a trough east of the area, and high pressure over the region. All in all, can not rule out any isolated or scattered afternoon showers and thunderstorms any day next week. Temperature forecast was a general blend of guidance, which is generally at or above normal through the period. && .AVIATION /06Z SATURDAY THROUGH WEDNESDAY/... VFR conditions expected today, with the possible exception of fog in the very near term at AGS. Main focus will be on tropical cyclone over the Atlantic progged to move NW towards the SC coast today and tonight, then slow down or become nearly stationary near the SC coast Sunday. Current satellite and surface obs indicate area of stratocumulus cloudiness, with CIGS above VFR level, near the coast drifting north. This would appear to preclude fog at OGB, and may impede fog at AGS later tonight, although appearance of clear skies at AGS in the very near term may allow some fog to form there. Latest array of high resolution models indicate shower activity ahead of the approaching cyclone could reach mainly the southern and eastern forecast area (FA) this afternoon, with some increasing chances of rain and associated lowering of CIGS tonight, again mainly CAE/CUB and OGB, with bulk of activity appearing to stay mainly east of AGS/DNL through tonight. EXTENDED AVIATION OUTLOOK...Restrictions probable in showers and possible thunderstorms Sunday and Sunday night, possibly lingering into Monday or longer, as a tropical system stalls or moves only slowly up the coast. && .CAE WATCHES/WARNINGS/ADVISORIES... GA...None. SC...None. && $$
Area Forecast Discussion National Weather Service Columbia SC 239 PM EDT FRI MAY 27 2016 .SYNOPSIS... High pressure will remain over the forecast area through tonight. Moisture will increase Saturday through Sunday associated with low pressure nearing the Southeast coast. && .NEAR TERM /THROUGH TONIGHT/... Cumulus continue developing across the Midlands and CSRA with a mid level cap suppressing any showers development. Clouds will dissipate with sunset and loss of heating with mostly clear skies expected through the early morning hours. System in the Atlantic will continue slowly moving toward the coast overnight with moisture and clouds ahead of the system reaching the coast around daybreak. As such expect some increasing clouds across the area during the early morning hours...however no showers are anticipated overnight. Low temperatures tonight will be in the lower 60s. && .SHORT TERM /SATURDAY THROUGH MONDAY NIGHT/... The NHC is monitoring the area of low pressure in the western Atlantic, and future forecasts will be based more on their guidance if the system develops sub-tropical or tropical characteristics. Models showing moisture increasing from the east through the day Saturday as an area of low pressure in the eastern Atlantic progresses westward towards the South Carolina Coast. The models are coming into a somewhat better agreement with the track and movement of the area of low pressure through the period. General consensus seems to bring the low towards the coast, moving inland somewhere north of Charleston, then slowing the low as it moves into eastern South Carolina. Models then trend towards moving the low northeastward as we move into Monday. For Saturday, expecting the morning to remain mainly dry across the cwa, then increasing shower and thunderstorm chances across the east during the afternoon. Rain/thunderstorm chances continue Sunday into Monday as the low slowly moves through the region. Highest chances for precip will remain greatest across the eastern counties, with pops trending lower the further west you go. Trended towards the WPC qpf amounts through the period. With the potential slow movement to the low, can not rule out periods of heavy rainfall which could produce localized flooding. Used the guidance consensus for the temperature forecast. && .LONG TERM /TUESDAY THROUGH FRIDAY/... Much uncertainty in the longer term forecast period. Models differ on the upper air solutions through the middle of the week, with the gfs showing a weak ridge north of the cwa and a weak low just east. The ecmwf shows a trough east of the area, and high pressure over the region. All in all, can not rule out any isolated or scattered afternoon showers and thunderstorms any day next week. Temperature forecast was a general blend of guidance, which is generally at or above normal through the period. && .AVIATION /18Z FRIDAY THROUGH WEDNESDAY/... VFR conditions to dominate the taf period...with early morning mvfr fog possible at AGS/OGB. Satellite imagery shows some cumulus have formed across the taf sites with the system in the Atlantic slowly moving west northwestward. expect cumulus to linger through the afternoon and evening hours then dissipate with sunset. Moisture will continue slowly increasing overnight with additional moisture arriving Saturday morning as winds turn northeasterly. Showers associated with the Atlantic system will move into the taf sites on Saturday reaching OGB around midday and the remainder of the sites just after the end of the period. As such have included VCSH for OGB near the end of the period with no mention elsewhere. Winds will be light and variable overnight then become northeasterly at 8 knots or less from 14z onward. EXTENDED AVIATION OUTLOOK...Restrictions probable in showers and thunderstorms Saturday through Monday as a system moves into the area from the Atlantic Basin. && .CAE WATCHES/WARNINGS/ADVISORIES... GA...None. SC...None. && $$
Area Forecast Discussion National Weather Service Charleston SC 159 PM EDT FRI MAY 27 2016 .SYNOPSIS... Atlantic high pressure will prevail today. A wave of low pressure will develop over the southwest Atlantic and approach the Southeast coast Saturday and Sunday. The low could affect the area into early next week before eventually lifting northeast. && .NEAR TERM /THROUGH TONIGHT/... Today: deep layered dry air and subsidence will maintain mostly sunny skies with highs in the mid to upper 80s. Few to scattered cumulus will likely develop along the sea breeze and quickly push inland this afternoon given the prevailing onshore flow. Tonight...Mainly clear skies this evening will give way to an increase in clouds along and east of I-95 later tonight. Deeper moisture ahead of an advancing inverted trough and surface low pres north of the Bahamas will be approaching the Carolina Coast. Model timing and low level convergence patterns remain consistent and we maintained a slight chance of showers late tonight with chance pops along upper Charleston County nearing daybreak. Given the advancing cloud shield late...some lows may be reached earlier in the overnight with rising temps along coastal areas late. && .SHORT TERM /SATURDAY THROUGH MONDAY/... The forecast through the short term period remains quite complex and uncertain as it is dependent on the evolution of developing low pressure over the western Atlantic. An area of low pressure will be located around 250-300 miles off coastal SC/GA Saturday morning. The strength and classification of the low is still uncertain, however the latest National Hurricane Center outlook indicates that the low has a high likelihood of becoming a tropical or sub-tropical system within 48 hours. A reconnaissance AIRCRAFT is scheduled to investigate the system Friday afternoon. Models are in fairly good agreement that the low will track northwest towards the SC coast Saturday into Saturday night. Thereafter, model solutions diverge. Consensus takes the low into Charleston county sometime Sunday afternoon. Regardless of whether or not this system is classified as tropical, the primary hazard of interest at this time is potential heavy rain. Should persistent heavy rain affect coastal areas coincident with high tide, the threat for localized flooding will be enhanced. Currently, the SC coast looks to have the biggest threat for heavy rain/localized flooding. Of course, a shift in forecast track could result in a different scenario. Continued uncertainty into Monday as the low could meander over the area or in the vicinity. GFS and NAM keep the low spinning in the vicinity for a couple days, while the Euro is more progressive and has it lifting northeast pretty quickly, similar to it`s run 24 hours ago. Overall, the weather will be fairly unsettled given the deep-layered moisture in place and the low pressure system in the vicinity. The forecast features at least chance POPs through the period, highest on Sunday. Needless to say, significant adjustments will likely be needed with future forecast packages when details are better defined. && .LONG TERM /MONDAY NIGHT THROUGH THURSDAY/... Forecast for the work week continues to be quite uncertain as it remains highly dependent on the evolution of a low pressure system that will impact the Southeast. A couple models are more progressive in lifting the low northeast away from the area quickly leaving a rather benign weather pattern mid week, while others want to keep it spinning in the vicinity before eventually dissipating. Have maintained rain chances in the forecast through the period. && .AVIATION /18Z FRIDAY THROUGH WEDNESDAY/... VFR at KCHS/KSAV through 12Z Sat though there is a small chance for MVFR ceilings at KCHS around daybreak Sat. Increasing chances for showers moving into the KCHS terminal during the day Sat but the best chances will be after 18Z when the Atlantic low moves closer to the coast. EXTENDED AVIATION OUTLOOK...Chances for at least periodic flight restrictions this weekend into early next week as a low pressure system approaches from the southeast. && .MARINE... Low pressure northeast of the Bahamas and sprawling high pressure from Bermuda to the mid-Atlantic states will maintain onshore flow through tonight. Slowly backing wind directions will range ENE to E 10 kt or less this morning, increasing to near 15 kt tonight. Seas will be on a slow uptick with 2 ft heights building to 3 to 4 ft tonight. Saturday through Wednesday: The marine forecast remains low confidence as it is highly dependent on evolution of a low pressure system over the Western Atlantic. On Saturday, pressure gradient will tighten as an area of low pressure lifts northeast towards the area and potentially develops into a tropical or sub-tropical system. This will result in northeast winds increasing to 15-20 knots. Thereafter, models differ greatly on the strength and track of the low, but general consensus takes the low into Charleston county Sunday afternoon. Then, it could either lift northeast or remain spinning in the vicinity through early next week. Given this uncertainty, significant changes should be expected in future forecast packages. Rip Currents: An increased risk of rip currents for the upcoming holiday weekend appears likely as onshore flow and swell energy increases in advance of an approaching low pressure system. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...None. SC...None. MARINE...None. && $$ SYNOPSIS... NEAR TERM...JRL SHORT TERM...ECT LONG TERM...ECT AVIATION...ECT/JRL MARINE...ECT Area Forecast Discussion National Weather Service Peachtree City GA 252 PM EDT SAT MAY 28 2016 .SHORT TERM /Tonight through Sunday Night/... North and central Georgia area sits between TD #2 - which is approx. 150 miles off the South Carolina coast - and a weakening upper level wave over the lower MS Valley. 12Z sounding at ATL measured a very dry 0.71" precipitable water value. Dry air is being mixed well down to the surface with 18-19z dewpts dropping to the upr 40s-lwr 50s across much of the area. Visible satellite imagery shows eroding CU field expanding around ATL metro area as mixing occurs. Next update from National Hurricane Center is not until 5PM EST but all signs point to TD #2 becoming Tropical Storm Bonnie. Mid and high level moisture (clouds) will continue to increase across the area tonight. Daytime heating will help trigger widely scattered showers w/ isold storms from Sandersville to Vidalia through sunset this evening, otherwise much of the area will remain dry tonight. By Sunday, as TD #2 (potential TS Bonnie) moves just inland along the SC coast, the potential for showers/isold storms will increase across northeast and east-central Georgia, mainly east/north of I-75 and I-16. Not expecting much westward progression of rain/storms due to upr lvl ridge building across MS and AL. Little change in temps tonight through tomorrow night. As tropical "low" advances inland, sfc winds will become more Northerly with some gusts 20-25MPH possible across our far southeastern counties - Milledgeville to Swainsboro to Eastman. DJN.83 .LONG TERM /Monday through Saturday/... Overall forecast thoughts parallel previous shift with limited pops through early week, then increasing diurnal storm chances mid week onward. Best rain chances still appear to be later in the week and into the weekend. Have only made minor adjustments to the max/min temperatures and weekend pops to account for latest model trends. Previous forecast discussion still applies and is included below. 31 Models in better consensus with main influencing features of fcst period. The either tropical depression or storm approaching the SC coast should slowly turn north to NE late Sunday then hug the coastline placing it off the NC Outerbanks by late Wednesday. Weak subsidence west of this system should limit diurnally driven convection across the CWA into Monday then the chances gradually increase thru the week with greatest potential Wednesday thru Friday as we get a south to southwest fetch of deep gulf moisture and ramped up instability. Some discrepancies exist among guidance in the evolution of a weak 850-mb low translated from an amplifying upper trough into the southeast CONUS by Friday/Saturday. While this could serve to focus more organized or widespread storm development...the environment should be favorable of at least scattered coverage anyway with daytime heating. Above normal temps /AOA 3-7 degrees more than climo/ are on tap this week with Tuesday expected to be the warmest as progged highs in the upper 80s to low 90s should be reached for most areas. Better cloud coverage and storm potential after midweek should keep local temps moderated a bit more. Baker && .AVIATION... 18Z Update... VFR conditions will prevail this period. Increasing mid and high level moisture from TD #2 will work northwest across central/north GA through tonight. Easterly sfc winds will gradually become north-northwest by midday Sunday as Tropical Low (TD #2) moves inland across South Carolina. Any organized convection should remain east of ATL but cannot rule out a pop-up -SHRA after 15z Sunday. //ATL Confidence...18Z Update... Medium to High on wind direction/shift to NW Sunday. High all other elements. DJN.83 && .PRELIMINARY POINT TEMPS/POPS... Athens 63 84 65 90 / 20 30 20 20 Atlanta 67 86 68 88 / 5 20 10 20 Blairsville 58 82 62 83 / 10 30 20 30 Cartersville 60 88 62 89 / 10 20 10 20 Columbus 65 89 67 91 / 5 10 10 20 Gainesville 65 84 66 87 / 10 20 20 20 Macon 63 88 64 91 / 10 10 10 20 Rome 60 89 64 89 / 10 10 10 20 Peachtree City 61 87 63 89 / 5 10 10 20 Vidalia 68 86 67 90 / 20 20 10 20 && .FFC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...DJN.83 LONG TERM....31 AVIATION...DJN.83
  [top] Area Forecast Discussion National Weather Service Columbia SC 229 PM EDT SAT MAY 28 2016 .SYNOPSIS... Tropical depression two is currently about 190 miles south southeast of Charleston and is moving to the northwest at 13 mph. Strengthening to a tropical storm is expected tonight with the storm reaching the Charleston coast Sunday morning. Sunday afternoon the storm is expected to to northeasterly and move very slowly along the coast Monday and Tuesday. Chances of rain will increase over the area through Sunday the lower for Monday and Tuesday. Potential exists for locally heavy rainfall through Monday. && .NEAR TERM /THROUGH TONIGHT/... Tropical depression 2 remains well offshore with satellite imagery showing a large area of convection on the northwest side. Area WSR-88D network shows showers beginning to reach the coast with a few isolated showers reaching the eastern Midlands. Winds currently across the area are 5 to 8 mph with winds along the coast around 10 mph. Showers have begun moving into the far eastern Midlands and will expand into the central Midlands late this afternoon and the western Midlands this evening. Although there is potential for thunderstorms currently coverage remains limited so will remain with slight chance of thunderstorms. Winds overnight will accelerate slowly with the eastern Midlands seeing around 10 mph with gusts to 20 mph by daybreak Sunday and lower speeds elsewhere. Main concern overnight will be potential for locally heavy rain...however with highest moistures not arriving until late in the period do not expect any flooding issues overnight. High temperatures this afternoon remain on track for the lower to middle 80s with overnight lows in the middle to upper 60s. && .SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/... TD2 should be moving onshore south of Charleston during the morning on Sunday before slowing the system down significantly through the late morning just after landfall. The forecast track then begins to push it more north/northeast parallel to the coast into sunday night. The models all bring plenty of moisture into the region by Sunday morning, especially in areas just to the north of the track. This will bring plenty of showers and isolated storms to the eastern half of the cwa. Expect to see some wraparound moisture to possibly making it back towards the csra through the day also. Storm total QPF amounts of between 1 to 3 inches with isolated higher amounts will be possible across the eastern Midlands, Pee Dee, and Catawba areas. Across the Western Midlands and much of the CSRA, expecting up to an inch, with isolated higher amounts. Biggest issues should revolve around urban and small stream flooding potential more than anything. As the low pushes northeast of the cwa Sunday night into Monday, the rain chances will decrease. However still expect to see at least a slight chance of a shower through the remainder of the period. Temperatures on Sunday will be tricky. With plenty of cloud cover and rainfall, temperatures may struggle to get out of the 70s for many areas. Areas outside of the rainfall may be able to actually climb into the 80s. Readings return a little closer to normal for Sunday night through Monday night. && .LONG TERM /TUESDAY THROUGH SATURDAY/... Models have come into a little better agreement on a deep trough moving from west to east toward the end of next week into next weekend. Will continue with the diurnal trend of isolated to scattered afternoon shower and thunderstorm through much of next week, with increasing rain chances late in the period just ahead of the next cold front. Have stayed close to current forecast which is for temperatures to remain generally at or slightly above normal through the period. && .AVIATION /19Z SATURDAY THROUGH THURSDAY/... VFR conditions expected through this evening with MVFR for much of tonight. Tropical depression 2 continues to approach the SC coast and will be just off the CHS coast by daybreak Sunday. Clouds associated with a large area of convection on the northwest side of the storm continue to move onshore and will move into the taf sites over the next several hours. Due to the isolated nature of thunderstorms associated with the system have remained without mention of thunder in the tafs. Main concern through the period will be the potential for locally heavy rainfall...with the greatest chance of heavy rain toward daybreak Sunday at CAE/CUB/OGB. Winds will slowly accelerate overnight with gusts up to 17 knots beginning around 10z at OGB and 14z elsewhere EXTENDED AVIATION OUTLOOK...Restrictions probable in showers and possible thunderstorms continuing through Monday as the tropical system moves very slowly northeastward along the coast. && .CAE WATCHES/WARNINGS/ADVISORIES... GA...None. SC...None. && $$ SYNOPSIS...99 NEAR TERM...99 SHORT TERM...99 LONG TERM...99 AVIATION...99
Area Forecast Discussion...UPDATED National Weather Service Peachtree City GA 148 PM EDT SAT MAY 28 2016 .UPDATE... For 18Z Tafs (aviation). && .PREV DISCUSSION... /Issued 735 AM EDT SAT MAY 28 2016/ SHORT TERM /Today through Sunday/... Tropical depression two will be moving northwestward toward the SC coast during the short term period. At this time...at least part of GA should be under the subsidence around the depression...however a few showers and thunderstorms approaching the east central zones are possible. So...have continued with slight chance pops for that area this afternoon and tonight. Also...the far northwest corner of the state may be affected by the increase in southerly moist flow into the central Gulf Coast area. a slight chance of convection still looks reasonable for the area north and west of Cedartown to Ellijay for this afternoon. Depending on the location of the depression on Sunday...it may be possible for showers or thunderstorms to circulate into GA. The westward extent of any precipitation is still questionable. For now...chance or slight chance pops have been included for much of the north and east central zones for Sunday. 41 LONG TERM /Sunday Night through Friday/... Models in better consensus with main influencing features of fcst period. The either tropical depression or storm approaching the SC coast should slowly turn north to NE late Sunday then hug the coastline placing it off the NC Outerbanks by late Wednesday. Weak subsidence west of this system should limit diurnally driven convection across the CWA into Monday then the chances gradually increase thru the week with greatest potential Wednesday thru Friday as we get a south to southwest fetch of deep gulf moisture and ramped up instability. Some discrepancies exist among guidance in the evolution of a weak 850-mb low translated from an amplifying upper trough into the southeast CONUS by Friday/Saturday. While this could serve to focus more organized or widespread storm development...the environment should be favorable of at least scattered coverage anyway with daytime heating. Above normal temps /AOA 3-7 degrees more than climo/ are on tap this week with Tuesday expected to be the warmest as progged highs in the upper 80s to low 90s should be reached for most areas. Better cloud coverage and storm potential after midweek should keep local temps moderated a bit more. Baker && .AVIATION... 18Z Update... VFR conditions will prevail this period. Increasing mid and high level moisture from TD #2 will work northwest across central/north GA through tonight. Easterly sfc winds will gradually become north-northwest by midday Sunday as Tropical Low (TD #2) moves inland across South Carolina. Any organized convection should remain east of ATL but cannot rule out a pop-up -SHRA after 15z Sunday. //ATL Confidence...18Z Update... Medium to High on wind direction/shift to NW Sunday. High all other elements. DJN.83 && .PRELIMINARY POINT TEMPS/POPS... Athens 86 64 86 66 / 5 20 30 20 Atlanta 86 66 87 69 / 5 5 20 10 Blairsville 82 60 82 62 / 10 10 30 20 Cartersville 87 62 88 65 / 10 10 20 10 Columbus 87 66 89 70 / 5 5 10 10 Gainesville 84 65 85 66 / 5 10 20 20 Macon 88 64 89 66 / 10 10 10 10 Rome 87 62 89 65 / 20 10 10 10 Peachtree City 86 61 87 65 / 5 5 10 10 Vidalia 86 67 87 70 / 20 20 20 10 && .FFC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...DJN.83 LONG TERM....31 AVIATION...DJN.83
  [top] Area Forecast Discussion National Weather Service Charleston SC 732 AM EDT SAT MAY 28 2016 .SYNOPSIS... Tropical Depression Two over the southwest Atlantic will approach the South Carolina coast through tonight, before moving onshore over Sunday before weakening. The low could linger in the vicinity into early next week before eventually lifting away to the northeast. A cold front will approach the region late next week. && .NEAR TERM /THROUGH TONIGHT/... Today: Tropical Storm Warnings remain in effect for the South Carolina Coastal areas. This ahead of the early season tropical system expected to remain a depression for much of the day prior to reaching the Gulf Stream tonight. Deep moisture will continue to advect into the Coastal Carolinas today with bands of showers expected to increase in coverage across Eastern South Carolina; especially during the afternoon hours from Beaufort northward. Widespread clouds will hold temps down into the lower 80s across northern zones. Across inland Georgia, only some high clouds to start the day and models indicate a fair amount of destabilization by the afternoon. we maintain a slight chance of showers and tstms to the west of I-95 this afternoon as convection will tend to be more diurnal bound on a decent 850 MB theta-e ridge across our inland Georgia Zones. It will become breezy along coastal areas this afternoon as the sea breeze develops along with various mesoscale shower bands. Tonight...The tropical low will reach the Gulf Stream waters and just about all of the model guidance indicates that any strengthening should be modest as upper level wind shear atop the system is forecast to remain rather substantial. Pops will be categorical across across much of the Charleston Tri-County area as strong low level convergence and deep tropical moisture with pwats of 2 inches or better in place. Rain will likely be heavy at times with potential for tstms. Most of the rain will likely fall to the north of the Savannah River overnight. Winds ahead of the tropical system will ramp up along the coast with potential of tropical storm force winds in the warning area. && .SHORT TERM /SUNDAY THROUGH TUESDAY/... The forecast through the short term period continues to remain quite complex and still somewhat uncertain, highly dependent upon the evolution of Tropical Depression Two over the southwest Atlantic between Bermuda and the Bahamas. The official forecast from the National Hurricane Center continues to track a weakening tropical storm/depression along coastal Charleston County on Sunday Afternoon. Gusty winds associated with the low are expected to gradually subside as the low either stalls or hooks briefly before beginning to slide slowly to the northeast sunday night. the ECMWF had an interesting solution on the 00Z run with a good bit of upper forcing from a 45 kt upper jet streak enhancing heavy rain across the South Carolina forecast area on the western side of the surface low. The QPF differences between the models remain quite substantial and revolve not only on complex mesoscale details but on synoptic forcing and atop the system. We have bumped up QPF to 2-3 inches across the Charleston Tri-County but some higher amounts could fall back west into places like Hampton and Allendale Counties. Due to the small and likely compact nature to the system there will likely only be some occasional convective bands that contain thunder storms, so we are showing no more than chance t-storms through the period. If deep convection were to develop on a knot near the center, there could be small chances for rotation given 25-30 kt of deep layered shear but the window at this time appears too small to play any tornado risk across Eastern Charleston and Berkeley Counties.The risk for Tropical Storm force winds will be highest Tonight into early Sunday as the storm reaches the coast. the areas most likely to experience Tropical Storm winds with gusts up to 40 mph, will be immediate coastal South Carolina, including the Charleston metro. Winds of this magnitude may bring down a few trees and powerlines. Some power outages are possible. Model solutions still vary on the evolution of Tropical Depression Two into Tuesday, but consensus slowly lifts the weakening low northeast from north coastal South Carolina towards the North Carolina Outer Banks by Tuesday. Thus, the main window for any threats with this system will have ended. Assuming this track holds, precipitation chances should decrease through the day Monday as deepest moisture moves out of the area. Locations across southeast Georgia could very well be dry much of the day given the position relative to the low. Current forecast has PoPs ranging from 40-50% north to around 20% in the south. On Tuesday, rain chances revolve around the more typical summertime diurnal convection. High temperatures will be near normal in the mid 80s to around 90 (highest across southeast Georgia), with lows mainly in the upper 60s to around 70. && .LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/... Models are in fairly good agreement for the long term period. Weak pressure pattern will be in place for the latter half of the work week as whatever remnants of the tropical system remains meanders off the mid-Atlantic coast and eventually dissipates. A cold front is then forecast to approach the region Friday into Saturday, resulting in an increase in precipitation chances. Temperatures will be near to slightly above normal as heights aloft build. && .AVIATION /12Z SATURDAY THROUGH WEDNESDAY/... KCHS: VFR until later today. Could see cigs dropping to mvfr this afternoon or evening, as Tropical Depression 2 approaches. Showers associated with very out fringes of the system may develop in the vicinity by mid to late morning, but greater chances still appear to be in the late afternoon and evening hours. Diurnal enhancements including the sea breeze will result in some wind gusts near 20 kt this afternoon. Tonight rains will increase and become heavier, winds should become gusty as the gradient tightens but have not shown any gusts topping 20 kt as yet. KSAV: VFR conditions will likely persist. Deeper moisture is forecast to remain north of the terminal. There may be a few spotty light showers around the area this morning and again this afternoon into the overnight, but potential not enough to add any vchs or shra to the KSAV terminal forecast. EXTENDED AVIATION OUTLOOK...Chances for at least periodic flight restrictions into early next week, especially at KCHS, as the tropical system impacts coastal South Carolina. && .MARINE... Tropical Depression Two currently located around 265 miles southeast of Charleston this morning will track northwest towards the area today, and eventually move onshore somewhere in the vicinity of Charleston Sunday afternoon. Winds/seas will deteriorate as result, with tropical storm conditions expected over the nearshore SC waters (including the Charleston Harbor) and portions of the outer Georgia waters late tonight into Sunday, where Tropical Storm Warnings remain in effect. Some uncertainty still remains in the track of Tropical Depression Two, but consensus has the low meandering in the vicinity early Monday before slowly lifting to the northeast into Tuesday. Latest National Hurricane Center forecast indicates that the system will weaken as this occurs, so marine conditions are expected to steadily improve. Thereafter, winds/seas should remain below any headline criteria through late week. Rip Currents: A high risk of rip currents all beaches today and elevated risks into early next week. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...HIGH RISK FOR RIP CURRENTS through this evening for GAZ117-119- 139-141. SC...Tropical Storm Warning for SCZ045-047>052. HIGH RISK FOR RIP CURRENTS through this evening for SCZ048>051. MARINE...Tropical Storm Warning for AMZ330-350-352-374. && $$ SYNOPSIS... NEAR TERM... SHORT TERM...ECT LONG TERM...ECT AVIATION...ECT MARINE...ECT
Area Forecast Discussion...Updated for Aviation National Weather Service Peachtree City GA 735 AM EDT SAT MAY 28 2016 .SHORT TERM /Today through Sunday/... Tropical depression two will be moving northwestward toward the SC coast during the short term period. At this time...at least part of GA should be under the subsidence around the depression...however a few showers and thunderstorms approaching the east central zones are possible. So...have continued with slight chance pops for that area this afternoon and tonight. Also...the far northwest corner of the state may be affected by the increase in southerly moist flow into the central Gulf Coast area. a slight chance of convection still looks reasonable for the area north and west of Cedartown to Ellijay for this afternoon. Depending on the location of the depression on Sunday...it may be possible for showers or thunderstorms to circulate into GA. The westward extent of any precipitation is still questionable. For now...chance or slight chance pops have been included for much of the north and east central zones for Sunday. 41 && .LONG TERM /Sunday Night through Friday/... Models in better consensus with main influencing features of fcst period. The either tropical depression or storm approaching the SC coast should slowly turn north to NE late Sunday then hug the coastline placing it off the NC Outerbanks by late Wednesday. Weak subsidence west of this system should limit diurnally driven convection across the CWA into Monday then the chances gradually increase thru the week with greatest potential Wednesday thru Friday as we get a south to southwest fetch of deep gulf moisture and ramped up instability. Some discrepancies exist among guidance in the evolution of a weak 850-mb low translated from an amplifying upper trough into the southeast CONUS by Friday/Saturday. While this could serve to focus more organized or widespread storm development...the environment should be favorable of at least scattered coverage anyway with daytime heating. Above normal temps /AOA 3-7 degrees more than climo/ are on tap this week with Tuesday expected to be the warmest as progged highs in the upper 80s to low 90s should be reached for most areas. Better cloud coverage and storm potential after midweek should keep local temps moderated a bit more. Baker && .AVIATION... 12Z UPDATE... VFR to continue for this cycle. Few to scattered 050-060 mainly during the afternoon. Winds east to southeast 6 to 9kt after 14z. Only isolated convection mainly north and east of the taf sites today. //ATL CONFIDENCE...12Z UPDATE... High on all elements. 41 && .PRELIMINARY POINT TEMPS/POPS... Athens 86 64 86 66 / 10 20 30 10 Atlanta 86 66 87 69 / 5 10 20 5 Blairsville 82 60 82 62 / 10 20 30 10 Cartersville 87 62 88 65 / 20 10 20 5 Columbus 87 66 89 70 / 5 10 5 5 Gainesville 84 65 85 66 / 5 20 30 10 Macon 88 64 89 66 / 10 10 20 5 Rome 87 62 89 65 / 20 10 20 10 Peachtree City 86 61 87 65 / 5 10 20 5 Vidalia 86 67 87 70 / 20 20 20 5 && .FFC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...41 LONG TERM....Baker AVIATION...41
Area Forecast Discussion National Weather Service Columbia SC 139 AM EDT SAT MAY 28 2016 .SYNOPSIS... High pressure will remain over the forecast area through tonight. Newly formed tropical depression two is forecast to become tropical storm Bonnie on Saturday and push into the coastal plain early Sunday. Chances of rain will increase over the weekend with potential for locally heavy rainfall. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... Moisture will begin increasing in advance of the approaching tropical depression two, with increasing mid to high level cloudiness expected. && .SHORT TERM /6 AM THIS MORNING THROUGH MONDAY NIGHT/... Tropical depression two will be steady moving northwestward approaching the coast on Saturday while a plume of deep tropical moisture moves inland over the forecast area with precipitable water values pushing well over 1.5 inches. Expecting Saturday morning to remain mainly dry across the cwa, then increasing shower and thunderstorm chances across the east during the afternoon. Rain/thunderstorm chances continue Sunday into Monday as the low slowly moves through the region. Highest chances for precip will remain greatest across the eastern counties, with pops trending lower the further west you go. Trended towards the WPC qpf amounts through the period due to wide spread in the forecast qpf guidance. With the potential slow movement to the low, can not rule out periods of heavy rainfall which could produce localized flooding. Used the guidance consensus for the temperature forecast. && .LONG TERM /TUESDAY THROUGH FRIDAY/... Much uncertainty in the longer term forecast period. Models differ on the upper air solutions through the middle of the week, with the gfs showing a weak ridge north of the cwa and a weak low just east. The ecmwf shows a trough east of the area, and high pressure over the region. All in all, can not rule out any isolated or scattered afternoon showers and thunderstorms any day next week. Temperature forecast was a general blend of guidance, which is generally at or above normal through the period. && .AVIATION /06Z SATURDAY THROUGH WEDNESDAY/... VFR conditions expected today, with the possible exception of fog in the very near term at AGS. Main focus will be on tropical cyclone over the Atlantic progged to move NW towards the SC coast today and tonight, then slow down or become nearly stationary near the SC coast Sunday. Current satellite and surface obs indicate area of stratocumulus cloudiness, with CIGS above VFR level, near the coast drifting north. This would appear to preclude fog at OGB, and may impede fog at AGS later tonight, although appearance of clear skies at AGS in the very near term may allow some fog to form there. Latest array of high resolution models indicate shower activity ahead of the approaching cyclone could reach mainly the southern and eastern forecast area (FA) this afternoon, with some increasing chances of rain and associated lowering of CIGS tonight, again mainly CAE/CUB and OGB, with bulk of activity appearing to stay mainly east of AGS/DNL through tonight. EXTENDED AVIATION OUTLOOK...Restrictions probable in showers and possible thunderstorms Sunday and Sunday night, possibly lingering into Monday or longer, as a tropical system stalls or moves only slowly up the coast. && .CAE WATCHES/WARNINGS/ADVISORIES... GA...None. SC...None. && $$
Area Forecast Discussion National Weather Service Columbia SC 239 PM EDT FRI MAY 27 2016 .SYNOPSIS... High pressure will remain over the forecast area through tonight. Moisture will increase Saturday through Sunday associated with low pressure nearing the Southeast coast. && .NEAR TERM /THROUGH TONIGHT/... Cumulus continue developing across the Midlands and CSRA with a mid level cap suppressing any showers development. Clouds will dissipate with sunset and loss of heating with mostly clear skies expected through the early morning hours. System in the Atlantic will continue slowly moving toward the coast overnight with moisture and clouds ahead of the system reaching the coast around daybreak. As such expect some increasing clouds across the area during the early morning hours...however no showers are anticipated overnight. Low temperatures tonight will be in the lower 60s. && .SHORT TERM /SATURDAY THROUGH MONDAY NIGHT/... The NHC is monitoring the area of low pressure in the western Atlantic, and future forecasts will be based more on their guidance if the system develops sub-tropical or tropical characteristics. Models showing moisture increasing from the east through the day Saturday as an area of low pressure in the eastern Atlantic progresses westward towards the South Carolina Coast. The models are coming into a somewhat better agreement with the track and movement of the area of low pressure through the period. General consensus seems to bring the low towards the coast, moving inland somewhere north of Charleston, then slowing the low as it moves into eastern South Carolina. Models then trend towards moving the low northeastward as we move into Monday. For Saturday, expecting the morning to remain mainly dry across the cwa, then increasing shower and thunderstorm chances across the east during the afternoon. Rain/thunderstorm chances continue Sunday into Monday as the low slowly moves through the region. Highest chances for precip will remain greatest across the eastern counties, with pops trending lower the further west you go. Trended towards the WPC qpf amounts through the period. With the potential slow movement to the low, can not rule out periods of heavy rainfall which could produce localized flooding. Used the guidance consensus for the temperature forecast. && .LONG TERM /TUESDAY THROUGH FRIDAY/... Much uncertainty in the longer term forecast period. Models differ on the upper air solutions through the middle of the week, with the gfs showing a weak ridge north of the cwa and a weak low just east. The ecmwf shows a trough east of the area, and high pressure over the region. All in all, can not rule out any isolated or scattered afternoon showers and thunderstorms any day next week. Temperature forecast was a general blend of guidance, which is generally at or above normal through the period. && .AVIATION /18Z FRIDAY THROUGH WEDNESDAY/... VFR conditions to dominate the taf period...with early morning mvfr fog possible at AGS/OGB. Satellite imagery shows some cumulus have formed across the taf sites with the system in the Atlantic slowly moving west northwestward. expect cumulus to linger through the afternoon and evening hours then dissipate with sunset. Moisture will continue slowly increasing overnight with additional moisture arriving Saturday morning as winds turn northeasterly. Showers associated with the Atlantic system will move into the taf sites on Saturday reaching OGB around midday and the remainder of the sites just after the end of the period. As such have included VCSH for OGB near the end of the period with no mention elsewhere. Winds will be light and variable overnight then become northeasterly at 8 knots or less from 14z onward. EXTENDED AVIATION OUTLOOK...Restrictions probable in showers and thunderstorms Saturday through Monday as a system moves into the area from the Atlantic Basin. && .CAE WATCHES/WARNINGS/ADVISORIES... GA...None. SC...None. && $$
Area Forecast Discussion National Weather Service Charleston SC 159 PM EDT FRI MAY 27 2016 .SYNOPSIS... Atlantic high pressure will prevail today. A wave of low pressure will develop over the southwest Atlantic and approach the Southeast coast Saturday and Sunday. The low could affect the area into early next week before eventually lifting northeast. && .NEAR TERM /THROUGH TONIGHT/... Today: deep layered dry air and subsidence will maintain mostly sunny skies with highs in the mid to upper 80s. Few to scattered cumulus will likely develop along the sea breeze and quickly push inland this afternoon given the prevailing onshore flow. Tonight...Mainly clear skies this evening will give way to an increase in clouds along and east of I-95 later tonight. Deeper moisture ahead of an advancing inverted trough and surface low pres north of the Bahamas will be approaching the Carolina Coast. Model timing and low level convergence patterns remain consistent and we maintained a slight chance of showers late tonight with chance pops along upper Charleston County nearing daybreak. Given the advancing cloud shield late...some lows may be reached earlier in the overnight with rising temps along coastal areas late. && .SHORT TERM /SATURDAY THROUGH MONDAY/... The forecast through the short term period remains quite complex and uncertain as it is dependent on the evolution of developing low pressure over the western Atlantic. An area of low pressure will be located around 250-300 miles off coastal SC/GA Saturday morning. The strength and classification of the low is still uncertain, however the latest National Hurricane Center outlook indicates that the low has a high likelihood of becoming a tropical or sub-tropical system within 48 hours. A reconnaissance AIRCRAFT is scheduled to investigate the system Friday afternoon. Models are in fairly good agreement that the low will track northwest towards the SC coast Saturday into Saturday night. Thereafter, model solutions diverge. Consensus takes the low into Charleston county sometime Sunday afternoon. Regardless of whether or not this system is classified as tropical, the primary hazard of interest at this time is potential heavy rain. Should persistent heavy rain affect coastal areas coincident with high tide, the threat for localized flooding will be enhanced. Currently, the SC coast looks to have the biggest threat for heavy rain/localized flooding. Of course, a shift in forecast track could result in a different scenario. Continued uncertainty into Monday as the low could meander over the area or in the vicinity. GFS and NAM keep the low spinning in the vicinity for a couple days, while the Euro is more progressive and has it lifting northeast pretty quickly, similar to it`s run 24 hours ago. Overall, the weather will be fairly unsettled given the deep-layered moisture in place and the low pressure system in the vicinity. The forecast features at least chance POPs through the period, highest on Sunday. Needless to say, significant adjustments will likely be needed with future forecast packages when details are better defined. && .LONG TERM /MONDAY NIGHT THROUGH THURSDAY/... Forecast for the work week continues to be quite uncertain as it remains highly dependent on the evolution of a low pressure system that will impact the Southeast. A couple models are more progressive in lifting the low northeast away from the area quickly leaving a rather benign weather pattern mid week, while others want to keep it spinning in the vicinity before eventually dissipating. Have maintained rain chances in the forecast through the period. && .AVIATION /18Z FRIDAY THROUGH WEDNESDAY/... VFR at KCHS/KSAV through 12Z Sat though there is a small chance for MVFR ceilings at KCHS around daybreak Sat. Increasing chances for showers moving into the KCHS terminal during the day Sat but the best chances will be after 18Z when the Atlantic low moves closer to the coast. EXTENDED AVIATION OUTLOOK...Chances for at least periodic flight restrictions this weekend into early next week as a low pressure system approaches from the southeast. && .MARINE... Low pressure northeast of the Bahamas and sprawling high pressure from Bermuda to the mid-Atlantic states will maintain onshore flow through tonight. Slowly backing wind directions will range ENE to E 10 kt or less this morning, increasing to near 15 kt tonight. Seas will be on a slow uptick with 2 ft heights building to 3 to 4 ft tonight. Saturday through Wednesday: The marine forecast remains low confidence as it is highly dependent on evolution of a low pressure system over the Western Atlantic. On Saturday, pressure gradient will tighten as an area of low pressure lifts northeast towards the area and potentially develops into a tropical or sub-tropical system. This will result in northeast winds increasing to 15-20 knots. Thereafter, models differ greatly on the strength and track of the low, but general consensus takes the low into Charleston county Sunday afternoon. Then, it could either lift northeast or remain spinning in the vicinity through early next week. Given this uncertainty, significant changes should be expected in future forecast packages. Rip Currents: An increased risk of rip currents for the upcoming holiday weekend appears likely as onshore flow and swell energy increases in advance of an approaching low pressure system. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...None. SC...None. MARINE...None. && $$ SYNOPSIS... NEAR TERM...JRL SHORT TERM...ECT LONG TERM...ECT AVIATION...ECT/JRL MARINE...ECT