River Flood Warning 34, NWS Austin/San Antonio, TX

Area Forecast Discussion
National Weather Service Austin/San Antonio TX
638 AM CDT Tue Jul 15 2025

...New AVIATION...

.KEY MESSAGES...

- Flood Watch remains in effect until 1 PM Tuesday for the Hill
  Country, southern Edwards Plateau, and portions of the Rio Grande
  Plains and I-35 corridor.

- Additional rainfall of 1-3 inches with isolated higher totals up
  to 6 inches possible mainly this morning. Additional river rises
  are possible.

- Drier conditions mid to late week with slightly higher
  temperatures.

&&

.SHORT TERM...
(Today through Wednesday)
Issued at 113 AM CDT Tue Jul 15 2025

As of about midnight Tuesday, scattered showers and storms
associated with an MCV near the Mexican border were beginning to
spread northward across the Rio Grande Plains and into the southern
Edwards Plateau. This activity is tapping into an overlapping
nocturnal intensification of the 850mb low level jet, which is
enhancing convergence within a plume of moist air with precipitable
water values nearing and exceeding 2 inches, corresponding to values
above the 90th percentile for this time of year. Additional showers
and storms are expected over the course of the early morning hours,
with some of the high-resolution models showing a gradual spread of
the rain envelope into the western Hill Country. Boundaries left
behind by storms earlier in the evening may also concentrate
additional downpours along north-to-south lines. The modeled
atmospheric conditions indicate an environment continuing to favor
efficient rainfall, leading to high rain rates which could locally
reach 2 inches per hour at times. The 00Z HREF LPMM indicated the
highest rain totals through this morning could approach 6 inches in
localized spots as showers continue to stream northward.

Much of Tuesday morning's rains will be falling atop sensitive soils
already moistened heavily by Monday morning's rains, leading to an
increased potential for runoff which could trigger flash flooding.
Given these factors, it is prudent to be weather aware and have
multiple methods of receiving weather warnings.

Southwesterly deep-layer flow should cause the overall area of heavy
rain showers and storms to gradually continue northeast during the
morning along with the MCV. Evolution of the MCV itself is
uncertain, though most models move its associated vorticity
northward. There should be a general decrease in the intensity and
coverage of rain late-morning and afternoon as the low-level jet
weakens. However, rains may continue to be enhanced near the MCV as
it drifts out of our area and draws in more unstable air. Most of
the high-resolution guidance has the MCV out of the CWA by Tuesday
evening with a subsequent decrease in rain chances over the area,
though there could be some reinvigoration of isolated showers with
daytime heating over South-Central Texas towards the late afternoon
and early evening.

As we head into Tuesday night into Wednesday, the growth of
subtropical ridging centered over the lower Mississippi Valley is
forecast to nudge the corridor of moist air and convergence farther
to the west, displacing it away from the Gulf and leading to a
reduction in moisture and rain chances. Wednesday looks dry for
most, though ridging appears relatively weak and could allow for an
isolated shower or storm accompanying onshore flow/seabreeze over
the Coastal Plains.

&&

.LONG TERM...
(Wednesday night through Monday)
Issued at 113 AM CDT Tue Jul 15 2025

Continued extension of the mid- to upper-level Gulf coast ridge into
our area should generally support an increase in daytime
temperatures during the mid to late week with mostly dry conditions.
While medium-range ensembles show a summertime ridge pattern
developing over the course of the week, we are monitoring a tropical
disturbance currently offshore the eastern coast of Florida. As the
ridge builds, this disturbance could track west along or parallel to
the northern US Gulf coast during the latter part of the week. Most
of the model guidance does not bring this feature as far west as our
area, though it will be worth keeping an eye on. Aside from this
disturbance, which could stick around into the weekend, there is
good consensus from ensemble guidance that the broader ridging
pattern holds through the weekend and into Monday with near average
temperatures.

&&

.AVIATION...
(12Z TAFS)
Issued at 633 AM CDT Tue Jul 15 2025

MVFR cigs are forecast for the I-35 sites and KDRT at least through
15Z today. VFR conditions return by 16Z for the I-35 airports and by
19Z for KDRT. A southerly flow around 10 to 15 knots with gusts of
20 to 25 knots is forecast through tonight. MVFR cigs return around
08Z Wednesday.

&&

.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry              94  76  96  74 /  10   0   0   0
Austin Bergstrom Intl Airport  94  75  96  74 /  10   0   0   0
New Braunfels Muni Airport     95  75  97  73 /  10   0   0   0
Burnet Muni Airport            91  73  92  71 /  20  10   0   0
Del Rio Intl Airport           91  77  96  76 /  30  10   0   0
Georgetown Muni Airport        93  74  94  72 /  10   0   0   0
Hondo Muni Airport             92  74  96  72 /  30  10   0   0
San Marcos Muni Airport        94  74  97  72 /  10   0   0   0
La Grange - Fayette Regional   93  75  94  74 /  10   0   0   0
San Antonio Intl Airport       94  77  96  74 /  10  10   0   0
Stinson Muni Airport           96  77  98  74 /  10  10   0   0

&&

.EWX WATCHES/WARNINGS/ADVISORIES...
Flood Watch until 1 PM CDT this afternoon for Bandera-Bexar-Blanco-
Burnet-Comal-Edwards-Gillespie-Hays-Kendall-Kerr-Kinney-Llano-
Maverick-Medina-Real-Travis-Uvalde-Val Verde-Williamson-Zavala.

&&

Short-Term...Tran
Long-Term...Tran
Aviation...17

Preliminary Local Storm Report
National Weather Service Austin/San Antonio TX
541 AM CDT Tue Jul 15 2025

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0525 AM     Flash Flood      3 NE Camp Wood          29.70N 99.98W
07/15/2025                   Real               TX   Law Enforcement

            Sheriffs office reported 5 feet of water
            over the road from Camp Wood Creek. Road is
            closed and impassable.

&&

CJM

Preliminary Local Storm Report
National Weather Service Austin/San Antonio TX
544 AM CDT Tue Jul 15 2025

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0525 AM     Flash Flood      2 NNW Camp Wood         29.69N 100.03W
07/15/2025                   Real               TX   Law Enforcement

            Sheriffs office reports that Ray McDonald
            Ranch Road is closed and impassable due to
            water over the road.

&&

CJM

Preliminary Local Storm Report
National Weather Service Austin/San Antonio TX
614 AM CDT Tue Jul 15 2025

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0545 AM     Flash Flood      Montell                 29.53N 100.02W
07/15/2025                   Uvalde             TX   Emergency Mngr

            EM reported there is 4 feet of water over
            Hwy 55 and water continues rising due to
            Montell Creek. Road is closed and
            impassable.

&&

CJM