Forecast Discussions mentioning any of
"ACARS" "MDCRS" "AIRCRAFT" "TAMDAR" "AMDAR" "WVSS" received at GSD on 09/22/19
Area Forecast Discussion...UPDATED
National Weather Service Austin/San Antonio TX
656 PM CDT Sat Sep 21 2019
A breezy southeast flow is in place across much of the area early
this evening. Winds are forecast to remain around 10 to 15 knot
range with gusts up to 25 knots through about midnight tonight.
VFR conditions are expected across all area sites through 04Z Sunday
with MVFR cigs anticipated for the I-35 terminals to begin around
05Z or short after. Current area radar images show isolated showers
nearby KSAT and KSSF, however, the trend is for these showers to
diminish and come to an end within the next few hours and HiRes
models agree on this solution. MVFR cigs will dominate the overnight
hours through late Sunday morning before clouds break for the return
of VFR conditions. Southerly flow continues on Sunday with speeds
ranging from 10 to 15 knots with higher gusts. Most showers and
storms to stay over the Coastal Plains on Sunday afternoon/evening.
.PREV DISCUSSION... /ISSUED 603 PM CDT Sat Sep 21 2019/
Deeper tropical moisture is draped along a Georgetown to Boerne to
Carrizo Springs line late this afternoon per GOES Total Precipitable
Water satellite imagery and have done a quick update to pull
isolated rain chances into the Hill Country and Highway 83 Corridor
based on latest radar trends. Aircraft soundings out of Austin and
San Antonio show weak mid-level lapse rates and overall
lightning/thunderstorm potential appears to remain low through the
early evening hours. Given the diurnally driven nature of these
showers, still anticipate loss of daytime heating to result in a
quick dissipation of this activity by 9 PM.
PREV DISCUSSION... /ISSUED 246 PM CDT Sat Sep 21 2019/
SHORT TERM (Tonight through Sunday)...
Isolated showers are ongoing across portions of the Coastal Plains
and even extending up into the San Antonio area where a plume of
elevated moisture exists. A few areas have picked up some wetting
rains, with Stinson airport on the southeast side of San Antonio
receiving a half inch of rain. Temperatures this afternoon are
primarily in the 90s, with a few cooler locations across the Hill
Country and where rain cooled air and increased cloud cover has kept
temperatures tempered. Shower activity should come to an end this
evening with the loss of heating. Expect partly to mostly cloudy
skies tonight with overnight lows in the mid 70s for most locations.
A few streamer showers are possible toward morning. Another
unseasonably warm day is expected on Sunday, with highs reaching the
mid to upper 90s for most locations. There will be another slight
chance for some showers, but the favored area will be pushed a little
bit further east to the Coastal Plains.
LONG TERM (Monday through Saturday)...
The mid to upper level high across the southeastern US will
generally stay in place through Monday before shifting further
southeast to the eastern Gulf of Mexico near Florida toward mid week.
An upper level trough is expected to come ashore in the Pacific
Northwest by Sunday evening, heading southeast and becoming a well
defined closed mid level low by Tuesday morning near the
California/Arizona/Mexico border. It is expected to generally hang
out in that area before becoming an open wave trough and existing to
the northeast. For us here across South Central Texas, not a whole
heck of a lot is expected to change, with south/southeasterly surface
flow and generally weak mid to upper level winds persisting. Slight
chance PoPs, high temperatures in the mid 90s, and lows in the mid
70s are expected to continue through the period. The Climate
Prediction Center`s 6 to 10 and 8 to 14 day outlooks continue to show
high probabilities for warmer than normal temperatures continuing,
and long term models continue to show no cold fronts on the horizon.
.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry 74 98 75 97 74 / 20 10 0 10 10
Austin Bergstrom Intl Airport 72 96 72 95 72 / 20 10 0 10 10
New Braunfels Muni Airport 72 97 72 96 72 / 10 20 0 10 10
Burnet Muni Airport 72 94 71 94 71 / 20 10 0 10 10
Del Rio Intl Airport 76 98 75 98 76 / - - 0 - 10
Georgetown Muni Airport 72 96 72 96 72 / 20 10 0 10 10
Hondo Muni Airport 74 99 73 100 73 / 10 10 - 10 10
San Marcos Muni Airport 72 97 72 96 72 / 10 20 0 10 10
La Grange - Fayette Regional 73 96 74 96 72 / 10 20 0 20 -
San Antonio Intl Airport 75 97 75 96 75 / 10 20 - 10 10
Stinson Muni Airport 75 99 75 99 75 / 10 20 - 10 10
Public Service/Data Collection...EWilliams
Area Forecast Discussion
National Weather Service Blacksburg VA
939 PM EDT Sat Sep 21 2019
High pressure will bring generally fair weather and warm
temperatures to the Appalachians and central mid Atlantic
region through the weekend. A weak cold front may bring some
showers to locations west of the Blue Ridge on Monday, but high
pressure will once again build over the area with a return to
fair weather through the middle of next week.
.NEAR TERM /THROUGH SUNDAY/...
As of 930 PM EDT Saturday...
Showers have finally tapered off this evening. Added fog to
areas that saw rain this afternoon and evening, particularly
Rockbridge and Amherst Counties and the New River Valley.
As of 720 PM EDT Saturday...
Isolated showers are fading this evening with lose of heating.
High pressure surface and aloft then brings another day of fair
weather with warmer temperatures to close out the weekend on
Lows tonight will be a few ticks warmer than last night with
readings in the lower 60s east of the Blue Ridge and mid to
upper 50s west. Highs on Sunday will be in the upper 80s to
near 90 east, low/mid 80s west.
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
As of 245 PM EDT Saturday...
The upper air pattern deamplifies briefly early in the week
allowing for a surface cold front to make passage Monday. The
front is expected to be moisture starved with High Pressure
over the Gulf Coast States blocking any substantial connection
to the Gulf. As such, the cold front will pass through the
forecast area within a westerly flow regime, causing most, if
not all, of the shower activity to dry up as the front crosses
the mountains Monday afternoon. Bottom line, little or no QPF is
expected with this frontal passage, most of which will be
confined to areas west of the Blue Ridge, and even then
generally netting less than a tenth of an inch.
Temperatures Monday should easily climb above normal east of the
Blue Ridge where the front is not expected to arrive until the
late afternoon or evening. Mountain locations should be closer
to normal, with clouds increasing Monday morning and helping to
offset the temperature rise.
Post frontal conditions Tuesday will place the forecast area
under dry air advection with surface High Pressure becoming re-
established...temperatures closer to the seasonal norm.
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
As of 300 PM EDT Saturday...
Flat mean flow is forecast for mid-week with another dry surface
frontal passage anticipated Thursday. After Thursday, a rapid
transition to high amplitude flow is forecast with a full
latitude long wave trof on the West Coast and an eastern U.S.
Ridge of High Pressure. Some of the models indicate the eastern
Ridge may gain an amplitude to something like we would see in
August with a 594-596 dm 500H anticyclone centered somewhere
vcnty of the mid-MS valley. As such this should effectively
block moisture over a big piece of real estate to include our
forecast area through next weekend, and potentially yielding a
dry finish to the last full week of September...the 6 to 10 day
outlook advertising temperatures well above normal and
precipitation below normal. With 850MB temperatures returning to
the +16 to +20 degree range, the possibility for a few more 90
degree days are still within reach in spite of the shortening
diurnal cycle and fall equinox.
.AVIATION /02Z SUNDAY THROUGH THURSDAY/...
As of 730 PM EDT Saturday...
Isolated showers are fading this evening. Expect IFR/LIFR
valley fog to develop late tonight with the best chance for poor
flight conditions at KLWB, possibly KBCB.
Winds will be light through the period with no impact to
aircraft operations expected.
.Extended Aviation Discussion...
A weak cold front may bring scattered MVFR showers on Monday.
High pressure then builds in behind the front with a return to
VFR conditions during the days and some IFR valley fog during
the nights through midweek.