442
FXUS64 KEWX 121953
AFDEWX

Area Forecast Discussion
National Weather Service Austin/San Antonio TX
253 PM CDT Mon May 12 2025

...New SHORT TERM, LONG TERM...

.SHORT TERM...
(Tonight through Tuesday night)
Issued at 241 PM CDT Mon May 12 2025

Key Messages:

- Record heat expected Tuesday.

- Heat Advisory has been issued Tuesday through mid-week.

South Central Texas now sits under northwest flow aloft as an upper
low remains to the east with a ridge axis west of Texas. A warm-up
continues today with afternoon highs peaking from the upper 80s to
right around 100 degrees. Some high clouds may spill into the area
from the northwest, but will do little to aid in cooling
temperatures. Temperatures will not approach daily records today,
but that changes tomorrow as we anticipate widespread triple digit
temperatures to return to the majority of South Central Texas. This
is due to a thermal ridge continuing to amplify and move east over
the area. Dry west to southwest wind will keep the hottest
temperatures tomorrow generally along and west of I-35, though a few
counties in the coastal plains will also see triple digits. A Heat
Advisory has been issued beginning Tuesday afternoon and continues
into Wednesday (see more about Wednesday in the extended
discussion). The only counties not included in the Heat Advisory on
Tuesday are DeWitt, Fayette, Lavaca and Lee Counties, but are
included for Wednesday. Lows tonight will generally be in the 60s
with even warmer lows up to the mid 70s Tuesday into Wednesday. Now
is the time to prepare for this early season prolonged heat event.

&&

.LONG TERM...
(Wednesday through Monday)
Issued at 241 PM CDT Mon May 12 2025

Key Messages:

- Daily and monthly high temperature records are at risk Wednesday
Thursday, and possibly Friday.

- Moderate to Major risk of heat-related impacts through the
upcoming weekend.

- Additional heat safety information and resources can be found at
the following websites: www.heat.gov and www.weather.gov/safety/heat

-Elevated to near critical fire weather concerns through the extended
 forecast period along and west of I-35 corridor.

The heat peaks on Wednesday with temperatures in the 103 to 106
range over the Hill Country, 101 to 106 along and east of I-35
corridor, and 103 to 114 across the southern Edwards Plateau, Val
Verde County, and the Rio Grande Plains. A Heat Advisory is in
effect for all of South Central Texas for Wednesday through 9 PM
CDT. There is a good chance for some areas of South Central Texas to
be upgraded to an Extreme Heat Warning if model data continues to
show a warmer trend as it is doing this afternoon during future
weather forecast packages. The heat wave continues into the latter
part of work week and into the upcoming weekend. Air temperatures are
forecasted to come down a few degrees (still above normal
temperatures) while increased moisture spreads across the local area,
especially along and east of the I-35 corridor. Heat index values
then go above air temperatures while reaching 103 to 108 range. With
all that said, it is going to be a hot work week across all of South
Central Texas that likely extends into the weekend and early next
week.

With the hot and dry weather conditions and somewhat light to breezy
winds come elevated to near critical fire weather concerns mainly
along and west of I-35 corridor throughout the extended forecast
period.

We do have a slight chance for showers and storms Saturday, Sunday,
and Monday afternoons/early evenings across the Hill Country,
southern Edwards Plateau, and Rio Grande as an upper level low
pressure system digs down through the California coast and then moves
into the four corners region.

&&

.AVIATION...
(18Z TAFS)
Issued at 1142 AM CDT Mon May 12 2025

VFR conditions are expected through the period. Wind will generally
be light under 10 knots today with only some high clouds expected
over the area. After 00Z, southerly wind will prevail eventually
becoming gusty by mid-morning tomorrow at I-35 sites.

&&

.FIRE WEATHER...
Issued at 252 PM CDT Mon May 12 2025

Elevated to locally near critical fire weather conditions are
possible each afternoon through the upcoming weekend mainly along
and west of the I-35 corridor, including the Edwards Plateau and
Rio Grande. Today marks a transitional day between the slightly
cooler weather of the past weekend and a summer-like fire weather
pattern developing Tuesday and Wednesday. Light winds for the rest
of the afternoon generally below 8 mph sustained at 20 ft are
forecasted with minimum RH values of 10 to 20 percent along and
west of the I-35 corridor.

A drying and warming trend ramps on Wednesday, resulting in lower
RH values closer to 10 percent over the Rio Grande Plains and
southern Edwards Plateau with temperatures above 100F throughout
South Central Texas. Southerly flow is forecast each afternoon
along and east of I-35 with 10 to 15 mph winds. Areas west of I-35
may see a mix of 5 to 10 mph westerly to southerly winds due to
daily advances of the dry line. Temperatures tick down a few
degrees on Thursday and moisture increases slightly, resulting in
an increase in daily minimum RH values for a good portion of the
local area. However, afternoon RH values near 15 to 20 percent
may continue along the Rio Grande and southern Edwards Plateau
through the weekend. The dry potentially record-setting warmth
throughout the week could lead to more active fire weather
conditions going forward as fuels dry.


&&

.CLIMATE...
Issued at 252 PM CDT Sun May 11 2025

RECORD MAX TEMPERATURES TUESDAY THROUGH SATURDAY
(* TIED RECORD WITH MOST RECENT OCCURRENCE SHOWN)

         TUE       WED       THU       FRI       SAT
        05/13     05/14     05/15     05/16     05/17
------------------------------------------------------
AUS    94/1967*  96/2003   96/2003   97/2018*  97/2018
ATT    98/1925   97/2022   98/1925   99/2022*  99/2022
SAT    98/2009*  97/2022*  98/2022   97/2022* 100/2022
DRT   104/1995  103/2003  102/2022  107/2013  105/2013

RECORD MAX TEMPERATURES FOR MAY
-------------------------------
AUS   102 ... set on 05/07/1998
ATT   104 ... set on 05/24/1925
SAT   104 ... set on 05/31/2004
DRT   112 ... set on 05/26/2024

&&

.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry              65 103  73 105 /   0   0   0   0
Austin Bergstrom Intl Airport  62 102  70 106 /   0   0   0   0
New Braunfels Muni Airport     63 103  69 106 /   0   0   0   0
Burnet Muni Airport            64 103  72 106 /   0   0   0   0
Del Rio Intl Airport           68 108  74 110 /   0   0   0   0
Georgetown Muni Airport        63 102  73 106 /   0   0   0   0
Hondo Muni Airport             62 106  68 110 /   0   0   0   0
San Marcos Muni Airport        62 103  68 106 /   0   0   0   0
La Grange - Fayette Regional   64  98  69 101 /   0   0   0   0
San Antonio Intl Airport       65 104  71 107 /   0   0   0   0
Stinson Muni Airport           64 105  69 108 /   0   0   0   0

&&

.EWX WATCHES/WARNINGS/ADVISORIES...
Heat Advisory from 1 PM Tuesday to 9 PM CDT Wednesday for Atascosa-
Bandera-Bastrop-Bexar-Blanco-Burnet-Caldwell-Comal-Dimmit-Edwards-
Frio-Gillespie-Gonzales-Guadalupe-Hays-Karnes-Kendall-Kerr-Kinney-
Llano-Maverick-Medina-Real-Travis-Uvalde-Val Verde-Williamson-
Wilson-Zavala.

Heat Advisory from 1 PM to 9 PM CDT Wednesday for De Witt-Fayette-
Lavaca-Lee.

&&

$$

Short-Term...27
Long-Term...17
Aviation...27