498
FXUS64 KEWX 151758 AAA
AFDEWX

Area Forecast Discussion...UPDATED
National Weather Service Austin/San Antonio TX
1258 PM CDT Thu May 15 2025

...New AVIATION...

.UPDATE...
Issued at 947 AM CDT Thu May 15 2025

Updated the rest of the morning period to add a slight chance for
showers along the I-35 corridor. These light showers are elevated,
however, are reaching the ground. Expect dry weather conditions for
the afternoon the high temps in the upper 90s across the Hill Country
to 100 to 105 across and east of I-35, Coastal Plains, and Rio
Grande. Highest heat index values could reach the 107 to 109 range.

&&

.SHORT TERM...
(Today through Friday)
Issued at 133 AM CDT Thu May 15 2025

Key Messages:

- A Heat Advisory is in effect for parts of South Central Texas this
afternoon and evening.

- Hot temperatures continue Friday and additional heat products may
be needed.

Satellite shows scattered high clouds and a few patches of low
clouds over the area this morning. Lows will generally be in the
70s, though a few locations in the Hill Country or southern Edwards
Plateau could dip into the upper 60s. Later this morning, clouds
will clear a bit more with afternoon temperatures rising into the
mid 90s to around 105 degrees in the west. A dryline will move into
the area with most models stalling this feature just before it
reaches the Hill Country. Dewpoints in the 60s are expected ahead of
this line leading to some locations seeing heat index values from
100 to 108 degrees. The combination of temperatures and heat indices
warrants the continuation of the Heat Advisory for this afternoon,
mainly in the south/central portion of the CWA.

Moderate south to southeast flow will continue in the low levels
today which will allow for low cloud development tonight into Friday
morning for most of the area except the far west. This will keep
lows slightly warmer than early this morning.. High temperatures and
heat index values Friday will be similar to those of today, so
additional heat products may be needed. There is a low (15 to 20
percent) chance for thunderstorms in our far northeast late Friday
afternoon as the cap tries to erode, otherwise dry conditions are
expected.

&&

.LONG TERM...
(Friday night through Wednesday)
Issued at 133 AM CDT Thu May 15 2025

- Record breaking heatwave continues with additional temperature
  records likely being broken.

- Moderate to Major risk of heat-related impacts through the upcoming
  weekend and into early next week.

The weather pattern for the reminder of this week into the middle of
next week remains rather unchanged characterized by a broad, subtropical
ridge axis over Mexico into the Gulf with persistent southwesterly
flow aloft over south central Texas. Chances for isolated showers
and storms across the Hill Country and southern Edwards Plateau are
increasing for Saturday as the dryline temporarily surges eastward.
Temperatures will remain well above normal through the end of the
forecast period with high temperature records likely to be tied or
broken.

This heatwave will eventually become muggy and possibly even
downright oppressive across the area compared to the relatively dry
heat we have had the previous couple days. Heat index values of
100-110 are expected across the entire area and throughout the long
term. This pushes heat risk categories into the high to even extreme
category. If this trend continues we may need to issue additional
heat advisories for most. No matter how you slice it, it is going to
be a very hot weekend across all of South Central Texas that likely
extends into early next week. Please make sure you and your loved
ones have a way to stay cool during this early season heatwave.
Additional heat safety information and resources can be found at the
following websites:
www.heat.gov and www.weather.gov/safety/heat

As we head into next week, the heat continues though air temps start
slowly decreasing but the heat index or feels like remains in the
100-110 degree range. This is in response due to an upper- level
trough axis to our west which starts to deepen providing some weak
disturbances that move into the region. These disturbances will
limit just how high actual air temps can go due to increased moisture
and abundant cloud cover. In response rain chances look to increase
across the Hill Country into the I-35 corridor with the best chances
being Saturday afternoon/evening and again late Monday into Tuesday.
It is still too soon to discuss exact timing and amounts but due to
these disturbances being over 3 days out we are starting to see
models come into better agreement. Toward the end of the forecast
period, a couple of the global models show a cold front moving in
from the north. Overall confidence is low, but this may bring some
temporary relief from the heat.

&&

.AVIATION...
(18Z TAFS)
Issued at 1241 PM CDT Thu May 15 2025

VFR conditions are forecasted to remain through early overnight
period. Around 07Z/08Z Friday, MVFR cigs develop to affect the I-35
corridor terminals through about 16Z Friday. VFR conditions return
late morning and continue through Friday night. Southerly winds
prevail across the I-35 terminals through the forecast period. KDRT
has a wind shift to the northwest Friday afternoon in the wake of the
dryline.

&&

.FIRE WEATHER...
Issued at 257 PM CDT Tue May 13 2025

Elevated fire weather conditions continue this afternoon as humidity
drops into the single digits and teens behind a dryline moving into
the southern Edwards Plateau and Rio Grande Plains. Over these
locations, north to northwest wind will mainly be in the 5 to 12 mph
range. Very low humidity continues in the far west Friday, but wind
should be light over this area Friday afternoon.

&&

.CLIMATE...
Issued at 257 PM CDT TUE May 13 2025

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

         THU       FRI       SAT
        05/15     05/16     05/17
--------------------------------------------
AUS    96/2003   97/2018*  97/2018
ATT    98/1925   99/2022*  99/2022
SAT    98/2022   97/2022* 100/2022
DRT   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              76  99  75  99 /  10  10  10  20
Austin Bergstrom Intl Airport  75 100  74  99 /  10  10  10  10
New Braunfels Muni Airport     75 101  75 100 /  10  10  10  10
Burnet Muni Airport            74  98  74  97 /   0  20  10  30
Del Rio Intl Airport           74 104  79 104 /   0   0  10  20
Georgetown Muni Airport        74  98  75  98 /  10  10  10  20
Hondo Muni Airport             73 103  73 101 /   0   0  10  10
San Marcos Muni Airport        74 100  74 100 /  10  10  10  10
La Grange - Fayette Regional   76  96  76  96 /   0   0   0  10
San Antonio Intl Airport       76 101  76 101 /   0  10  10  10
Stinson Muni Airport           76 102  77 101 /   0   0  10  10

&&

.EWX WATCHES/WARNINGS/ADVISORIES...
Heat Advisory until 8 PM CDT this evening for Atascosa-Bexar-Frio-
Medina-Uvalde-Wilson.

&&

$$

Short-Term...17
Long-Term...76
Aviation...17