Forecast Discussions mentioning any of "ACARS" "MDCRS" "AIRCRAFT" "TAMDAR" "AMDAR" "WVSS" received at GSD on 03/01/20

Area Forecast Discussion
National Weather Service Fort Worth TX
536 PM CST Sat Feb 29 2020 .SHORT TERM... /NEW/ /Through Sunday evening/ A warm and breezy day today across the region, with winds gusting upwards of 30 MPH at several of our observation sites. Temperatures have also soared into the 70s. This strong warm air advection is occurring in response to cyclogenesis along the lee of the Rocky Mountains. Aloft, a potent shortwave trough is digging into the Pacific Northwest. The differential cyclonic vorticity advection associated with this digging shortwave trough is aiding in the aforementioned surface cyclogenesis. This pattern will continue to dominate the weather through the short-term portion of the forecast. Tonight, a strong low-level jet (LLJ) is forecast to develop, with winds of 40+ KT at 2,000 ft AGL forecast by model guidance. This strong LLJ will transport moisture northward, leading to a surge of Gulf stratus across the eastern half of the CWA. As is typically the case, I-35/35W should be the approximate western boundary of this stratus. A little patchy drizzle will be possible as well for areas east of I-35/35W, but this would be very light, with no rainfall accumulations forecast. The gusty southerly winds will keep the boundary layer well-mixed enough to preclude any fog development. The stratus will hang around through the morning hours Sunday, but should dissipate from west to east as winds veer, and drier air works its way east. Later in the afternoon, a dryline will surge eastward. While decent instability will be present with dewpoints in the upper 50s beneath steep mid-level lapse rates, a very strong cap will also be in place. High-resolution model guidance and forecast soundings show convective inhibition (CINH) values in excess of 100 J/kg, thus without any strong upper-level support (which we will not have), the warm sector ahead of the dryline should remain capped. Still, a few models try to generate some light QPF, and there does appear to be more of a chance for showers/thunderstorms east of our CWA. For this reason, opted to include a low mention (including isolated thunder) in our very eastern fringes. These "conditional" thunderstorm days rarely produce much if anything at all, but given the strong instability and modest wind shear that will be present, we will leave the window open just a crack for that low-end potential for an isolated thunderstorm. Godwin && .LONG TERM... /Issued 307 PM CST Sat Feb 29 2020/ /Monday through Thursday/ The start of the work week will be warm with increasing rain chances toward mid-week. At this point in time, it appears that widespread rain with embedded thunderstorms are a good bet for just about all of North and Central Texas. There will be a risk for moderate to heavy rain which could result in some flooding. A severe weather risk does exist, but current thinking is that the window in which this occurs will be very limited (late Tuesday afternoon/evening) and over a small area (Central Texas/Brazos Valley). By Thursday, most areas should be largely rain/storm free with mostly clear conditions thereafter. Low clouds and drizzle will blanket at least the eastern half of the forecast area on Monday morning with pretty mild conditions to start the day. Morning lows will remain in the upper 50s to mid 60s with southerly breezes starting around 5 to 15 MPH. Daytime mixing should erode the cloud deck from west to east through the day and this will likely yield another elevated fire weather threat west of I-35 where winds will become southwesterly and increase into the 10 to 20 MPH range. Highs will climb 5 to 10 degrees above normal for most of North and Central Texas with forecast values in the low to mid 70s. Some areas immediately along the thermal axis may even climb toward 80 degrees. Rain chances on Monday have been lowered some as it appears that 850mb temperatures close to 14-14.5C are probable and this should keep a decent sized lid on any deep moist convection. Still, some showers beneath the cap will be possible, mainly across East Texas and immediately along the southward advancing cold front. I`ll add in a mention of isolated storms across East Texas/Brazos Valley where instability bubbles closer to 1000 J/kg. We`ll need to reassess the strength of the cap on Monday. If we get a bit more sun and/or a larger degree of moisture...updrafts may be able to tap into slightly greater instability. Given that deep layer shear is projected to be plentiful, there could be a risk for organized convection. The better risk for more organized convection will hold off until Tuesday afternoon/evening, however, as the aformentioned cold front stalls. Model guidance has slowed the progression of the upper trough (now slower and deeper) and this will have ramifications on the frontal position. Regardless of where the front stalls exactly, locations to the south of this feature will become modestly unstable. Instability will dwindle with northward extent from the surface front. Current thinking is that the front will stall near the US HWY 79 corridor, leaving parts of Milam...Robertson...and Leon counties in the warm sector and thus a severe weather risk. Stay tuned as we get a better handle on the position of the front. Ascent atop this front will lead to widespread rain and embedded storms through the day on Tuesday and into Wednesday. Storm total rain amounts range between 1-2" across the area with the greatest totals right now focused near and south I-20. Given rainfall tendencies over the last 30 to 60 days...there will likely be some flood potential as PWATs over 1" should allow for efficient rainfall producers and thus heavy rain will be a threat. Depending on the overall convective nature of activity, some flood headlines may be needed (mainly for main-stem river, lakes and creeks). Conditions should improve Thursday through the remainder of the week with temperatures near or just above normal as southerly flow returns. We`ll see some breezy conditions, but at this point in time, anticipated rainfall should mitigate any appreciable fire weather concerns. If rain amounts are underwhelming, we`ll need to examine this potential again. Bain && .AVIATION... /NEW/ /00Z TAFs/ Concerns -- Early morning MVFR stratus. Continued gusty S-SWly winds. Gusty Sly winds continue across the forecast area this evening, with most METAR sites reporting gusts of 20-30 KT. Winds will subside a little overnight, but sustained winds of 10-15 KT with gusts to around 20 KT will continue. Later this evening, a strong LLJ will develop, with winds in excess of 40 KT likely around 2 kft AGL. Low-level flow will be fairly unidirectional, which should preclude a greater risk for LLWS, but given the strength of the LLJ, lighter aircraft may experience some airspeed loss if departing after 03Z. This strong LLJ will also spread Gulf stratus northward. Expect CIGs at most TAF sites to drop to MVFR before daybreak, with MVFR persisting thru around 17-18Z. Strong low-level flow should prevent CIGs from dropping to IFR, but there is a weak possibility of some intermittent IFR CIGs at KACT. Opted to maintain MVFR from previous TAF issuance, but later forecasts may need to address this potential. All TAF sites should improve to VFR by early afternoon as increasing S-SWly winds bring in drier air, allowing CIGs to lift. Godwin && .PRELIMINARY POINT TEMPS/POPS... Dallas-Ft. Worth 57 75 60 75 49 / 0 0 0 20 30 Waco 57 73 60 75 52 / 0 0 0 10 30 Paris 55 69 60 72 54 / 5 10 5 30 30 Denton 56 77 58 75 50 / 0 0 0 20 30 McKinney 57 73 60 73 54 / 0 5 0 20 30 Dallas 59 75 60 75 56 / 0 5 0 20 30 Terrell 57 73 61 74 59 / 0 5 0 20 30 Corsicana 57 71 62 75 61 / 0 0 0 10 30 Temple 55 72 60 75 61 / 0 0 0 10 20 Mineral Wells 53 79 55 76 48 / 0 0 0 20 30 && .FWD WATCHES/WARNINGS/ADVISORIES... None. && $$ 37/92