557
FXUS64 KEWX 170631
AFDEWX

Area Forecast Discussion
National Weather Service Austin/San Antonio TX
131 AM CDT Sun May 17 2026

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

.KEY MESSAGES...

- Very warm with isolated storms possible late this afternoon and
this evening

- A wet and active pattern awaits starting early next week. Heavy
  rain could lead to localized flooding.

&&

.SHORT TERM...
(Today through Monday)
Issued at 129 AM CDT Sun May 17 2026

Expect another warm day for today with many topping out in the low
90s under mostly cloudy skies to perhaps mid 90s for those across the
Rio Grande Plains where more sun breaks out. Additionally, it will
be quite muggy as moisture increases due to strong southerly flow at
the surface. This flow will also help to push our PWATs above
climatological normals with values in the 1.6 to 1.8 inch range.
Most areas should continue to remain dry until later in the
afternoon/evening. Forecast soundings continue showing a moderate to
strong cap, so any potential ripples within the southwest flow aloft
thanks to the upper level short wave moving across the Southern
Plains could be just enough to weaken it which would open the door
for an isolated storm or two. With this increased moisture and
relatively high Precipitable water values any convection that does
manage to form could definitely drop a quick quarter to perhaps an
inch of rain in any of the heavier cells. Hi-res models have latched
onto this recently with a handful suggesting convection forming over
the western Hill Country and spreading eastward across the I-35
Corridor. The flip side of this due to the cap, is we could have
absolutely nothing happen and it just be a rather warm and muggy
day. Decided to continue to keep low chance pops (20% or less)
across these areas in case this scenario were to occur.

By Monday most activity if it develops should be well east of our
area lending to another warm and muggy day under mostly cloudy to
partly cloudy skies as moisture remains across the area. We could
see heat indices approach the low 100s for many areas with heat
indices above 105 possible across the Winter Garden and Rio Grande
Plains. We should have a stronger cap in place for Monday but it`s
possible we could see a storm try to break it, if it does we could
see heavy rainfall along with the potential for small hail and gusty
winds.

&&

.LONG TERM...
(Monday night through Saturday)
Issued at 129 AM CDT Sun May 17 2026

A big pattern change is forecasted for the long term as we remain
under southwest flow aloft which usually allows for disturbances to
impact our area and take advantage of the rich moisture and unstable
air in place. As such, it seems likely that multiple disturbances
could impact our area as a dryline will be situated just off to our
west across west TX and will try to advance eastward each day. This
should set off convection across northern Mexico that would work its
way across the Rio Grande Plains and Southern Edwards Plateau.
Depending on how robust this activity becomes will determine how far
eastward it advances. Additionally, a cold front located across the
Southern Plains will try to make its way southward across northern
Texas. By Wednesday most models have this front located somewhere
just to our north. As this front slides southward convection is
expected to blossom along it with many areas seeing a localized
heavy rainfall threat as this front slowly stalls somewhere across
the area. This now stationary front will be the continued focus for
additional shower and thunderstorm activity throughout the period as
we remain entrenched in a very moist airmass with continued
southwest flow aloft.

Even after this front moves through our area and or washes out, both
Global models continue to hint at this pattern continuing into and
even beyond next weekend as disturbances aloft continue to ride over
our area and ignite the potential for additional rounds of showers
and thunderstorms. While most of the rain will be beneficial for
many areas there are some beginning signs that we could see heavier
rounds that may lead to localized flooding concerns. However the
specific areas, amounts and placements are too early to discuss
until more details get ironed out. Bottom line is an active and wet
pattern looks likely for the entire area starting early next week.
Continue to check back as details continue to get clearer over the
coming days.

&&

.AVIATION...
(06Z TAFS)
Issued at 1218 AM CDT Sun May 17 2026

MVFR ceilings are rapidly spreading over the I-35 Corridor.
Ceilings will spread to DRT within the next few hours. All
terminals will be MVFR through the night with VFR conditions
returning by around noon. Winds will be from the southeast and
will be strong and gusty again. MVFR ceilings will return again
late tonight.

&&

.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry              91  78  93  78 /  10  20  20  10
Austin Bergstrom Intl Airport  91  79  93  79 /  10  20  10  10
New Braunfels Muni Airport     91  77  93  77 /  10  10  10  10
Burnet Muni Airport            86  75  88  75 /  10  20  30   0
Del Rio Intl Airport           96  78  99  78 /   0  10   0   0
Georgetown Muni Airport        90  77  91  77 /  10  20  20  10
Hondo Muni Airport             91  78  92  77 /  10  10  10  20
San Marcos Muni Airport        92  78  93  78 /  10  10  10  10
La Grange - Fayette Regional   91  79  91  78 /  10  10  10  20
San Antonio Intl Airport       91  78  93  78 /  10  10  10  10
Stinson Muni Airport           92  78  94  78 /  10  10  10  10

&&

.EWX WATCHES/WARNINGS/ADVISORIES...
None.
&&

$$

SHORT TERM...CJM
LONG TERM....CJM
AVIATION...05