981 
FXUS64 KEWX 130547 AAA
AFDEWX

Area Forecast Discussion...UPDATED
National Weather Service Austin/San Antonio TX
1247 AM CDT Mon Sep 13 2021

.AVIATION...06Z TAF Period

For AUS, SAT and SSF: After initial VFR conditions to start off the
TAF period, flight conditions deteriorate overnight and throughout 
the remainder of the TAF period thanks to IFR to MVFR ceilings with
increasing clouds, in addition to the increasing chances for rain
showers and thunderstorms. Have highlighted the potential for this
convection with VCSH and VCTS at the moment. Winds will trend of
light to moderate breezes that turn from more easterly during this
morning to a northerly direction by late in the TAF period given
influence and positioning of Tropical Storm Nicholas along the 
western Gulf coast. 

For DRT: VFR conditions persist with moderate breezes out of the
east-southeast. Inserted VCSH for this afternoon/evening as the
potential may exist for some activity from the east. Expect some
increase in clouds at times otherwise.

&&

.PREV DISCUSSION... /ISSUED 643 PM CDT Sun Sep 12 2021/ 

AVIATION.../00Z TAFs/
Flying conditions start VFR, become MVFR around midnight, then IFR 
early Monday morning as moisture continues to increase. CIGs slowly 
rise to MVFR by midday. SHRA and TSRA will develop and become more 
numerous on Monday and maintained the VCSH in the morning and VCTS 
midday through evening. The exception being KDRT. That site should 
remain VFR throughout the period with SHRA/TSRA staying east of 
there. However, brief MVFR CIGs are possible early in the morning. 
Easterly winds 5 to 12 KTs prevail, although, will be more variable 
and lighter overnight into the early morning. Wind gusts to 25 KTs 
are possible Monday afternoon into evening. 

PREV DISCUSSION... /ISSUED 412 PM CDT Sun Sep 12 2021/ 

UPDATE...

.TROPICAL STORM WATCH NOW IN EFFECT FOR OUR SOUTHEASTERN COUNTIES
DUE TO TROPICAL STORM NICHOLAS...

Tropical Storm Nicholas will move toward the middle Texas Coast
tonight and tomorrow moving inland Tuesday morning. On this track
tropical storm force winds will be possible over Karnes, DeWitt,
Lavaca, Gonzales, and Fayette Counties beginning Monday night and we
have issued a Tropical Storm Watch for this area. Tropical storm
force gusts will be possible around the periphery of this area. In 
addition, heavy rain is likely and is discussed in the long term 
section below.

PREV DISCUSSION... /ISSUED 259 PM CDT Sun Sep 12 2021/ 

SHORT TERM (Tonight through Monday Night)...
Dewpoints at this time versus yesterday have increased 12-18 degrees 
across the area, signaling changes are on the way for the forecast. 
Gulf moisture is on the increase as Tropical Storm Nicholas 
developed this morning in the southwestern Gulf of Mexico and some 
isolated showers can be noted in the far southern CWA this 
afternoon. This should be the norm through tonight with isolated to 
scattered showers continuing in this same general area.  As the 
system gets closer to the US coast tomorrow, we should see an uptick 
in activity tomorrow. PoPs for the eastern half of the area tomorrow 
will top out in the 60-70 percent range with lesser probabilities to 
the west. With the loss of daytime heating, PoPs should lower about 
30 percent vs the day time period Monday night. Rainfall amounts 
through tomorrow night should remain mostly below an inch for our 
area with the higher totals in the southeastern CWA. Highs tomorrow 
will range from the middle 80s to middle 90s with lows tonight and 
tomorrow night mostly in the lower 70s.

LONG TERM (Tuesday through Sunday)...
The NHC forecast takes Nicholas onto the Middle Texas Coast Tuesday
morning. Strong winds should remain near the coast and not reach our
CWA. The main threat will be continuing heavy rain over the Coastal
Plains. Rain chances will extend inland to Hill Country with likely
rain from Lee to DeWitt Counties. The official forecast takes the
center into Northeast Texas Wednesday. Rain chances over the eastern
half of our CWA will remain high through Wednesday evening. Rainfall
amounts will decrease as the center of Nicholas moves farther away.
On the current track rainfall totals from tonight through Wednesday
will range from one to three inches with isolated higher amounts over
Fayette, Lavaca, and DeWitt Counties. Farther west totals will
decrease to around 0.5 inches along I-35 and lesser amounts to the
west. These amounts are highly dependent on the track of the storm.
If it moves farther west the higher amounts will spread that way the
Coastal Plains will see higher amounts than our forecast now has.
Models have not yet settled on track with the ECMWF an outlier to the
west. If the track shifts eastward our rainfall totals will be lower.
Thursday through Sunday there will continue to be low chances for
convection over the east in onshore flow.

&&

.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry              84  72  85  73  86 /  60  40  50  40  50 
Austin Bergstrom Intl Airport  83  72  85  71  86 /  60  40  50  40  50 
New Braunfels Muni Airport     84  72  87  71  88 /  70  40  40  40  50 
Burnet Muni Airport            84  70  84  70  84 /  50  20  40  30  40 
Del Rio Intl Airport           91  72  94  73  97 /  20  10  10  10  20 
Georgetown Muni Airport        84  71  84  71  85 /  50  30  40  40  50 
Hondo Muni Airport             86  72  89  72  91 /  60  30  30  20  30 
San Marcos Muni Airport        83  71  85  71  87 /  70  40  50  40  50 
La Grange - Fayette Regional   83  73  84  74  86 /  70  50  60  50  60 
San Antonio Intl Airport       84  72  86  73  88 /  60  40  40  30  40 
Stinson Muni Airport           86  74  89  75  90 /  60  40  40  30  40 

&&

.EWX WATCHES/WARNINGS/ADVISORIES...
Tropical Storm Watch for De Witt-Fayette-Gonzales-Karnes-Lavaca. 

&&

$$

Short-Term/Aviation...Brady
Long-Term...Runyen