Alert archive / Texas / Flash Flood Warnings in 2026

Flash Flood Warning 100, NWS Austin/San Antonio, TX

August 28, 2026Bexar County, Comal County, Texas

NWS Austin/San Antonio, TX issued this flash flood warning at Aug 28, 2026, 9:09 PM CDT for Bexar County, Comal County, Texas. It was in force for 3 hr. 2 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Aug 28, 2026, 9:09 PM CDT (02:09 UTC)
Expired
Aug 29, 2026, 12:15 AM CDT
In force
3 hr
Issued by
NWS Austin/San Antonio, TX
Area
Storm-based polygon
Damage threat
Considerable
Flood severity
None

Counties Bexar County, TX, Comal County, TX

The radar

The Austin/San Antonio radar (KEWX), 36 km from the middle of the area, began a volume at 02:11 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

What was reported inside it

TimeReportWhereRemark
Aug 28, 9:34 PM CDTFLASH FLOOD1 Ne Hollywood Park, TXEmergency manager reports a water rescue on Loop 1604 west of Hwy 281.
Aug 28, 10:30 PM CDTFLASH FLOOD1 Nnw San Antonio, TX*** 1 FATAL *** Two people were in a drainage area during heavy rainfall when they were swept downstream. One person escaped while another drowned, with police and fire crew recovering the body at San Pedro Creek near West Quincy Street. Time is estimated.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

Did it verify

Verified. The Iowa Environmental Mesonet's Cow matched 2 storm reports to this flash flood warning; the first came 25 minutes after it went out.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The nearest sounding before it

Corpus Christi, TX (KCRP), launched 00:00Z, 2.2 hours before the alert went out and 227 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Corpus Christi, TX at 00:00Z on 2026-08-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 905 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Corpus Christi, TX at 00:00Z on 2026-08-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -6 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
905 J/kg
Mixed-layer CIN
-105 J/kg
Mixed-layer LCL
1554 m above ground
0-6 km bulk shear
16 kt
0-1 km storm-relative helicity
-6 m²/s²
0-3 km storm-relative helicity
27 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.2

Open this sounding in Storm Lab

The text

As transmitted.

498 
WGUS54 KEWX 290209
FFWEWX
TXC029-091-290515-
/O.NEW.KEWX.FF.W.0100.260829T0209Z-260829T0515Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Austin/San Antonio TX
909 PM CDT Fri Aug 28 2026

The National Weather Service in Austin/San Antonio has issued a

* Flash Flood Warning for...
  Northern Bexar County in south central Texas...
  South Central Comal County in south central Texas...

* Until 1215 AM CDT.

* At 909 PM CDT, Doppler radar and automated rain gauges indicated
  thunderstorms producing heavy rain across the warned area. Between
  2 and 3 inches of rain have fallen. Additional rainfall amounts of
  1 to 2 inches are possible in the warned area. Flash flooding is
  ongoing or expected to begin shortly.

  HAZARD...Life threatening flash flooding. Thunderstorms producing
           flash flooding.

  SOURCE...Radar and automated gauges.

  IMPACT...Life threatening flash flooding of creeks and streams,
           urban areas, highways, streets and underpasses.

* Some locations that will experience flash flooding include...
  San Antonio, Schertz, Converse, Universal City, Live Oak, Selma,
  San Antonio Int Airport, Randolph AFB, Leon Valley, Helotes, Kirby,
  Alamo Heights, Windcrest, Terrell Hills, Garden Ridge, Shavano
  Park, Hollywood Park and Olmos Park.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.

Be especially cautious at night when it is harder to recognize the
dangers of flooding.

Be aware of your surroundings and do not drive on flooded roads.

&&

LAT...LON 2969 9823 2963 9823 2959 9831 2956 9830
      2954 9826 2954 9825 2955 9826 2955 9825
      2956 9824 2954 9823 2945 9839 2938 9864
      2937 9879 2957 9878 2972 9846

FLASH FLOOD...RADAR AND GAUGE INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE

$$

MM

What forecasters said that day

The local office's own words before this flash flood warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Austin/San Antonio, TX wrote its last area forecast discussion before this flash flood warning went out at Aug 28, 6:18 PM CDT, 2 hours 51 minutes earlier. Its key messages:

  • Updated at 615 PM CDT Fri Aug 28 2026
  • Low to medium storm chances return this afternoon, otherwise hot and predominantly dry weather returns this weekend into next week.
Area forecast discussion, Aug 28, 6:18 PM CDT, 2 hours 51 minutes before
Area Forecast Discussion
National Weather Service Austin/San Antonio TX
618 PM CDT Fri Aug 28 2026

...New AVIATION...

.KEY MESSAGES...
Updated at 615 PM CDT Fri Aug 28 2026

- Low to medium storm chances return this afternoon, otherwise
  hot and predominantly dry weather returns this weekend into next
  week.

&&

.SHORT TERM...
(Tonight through Saturday night)
Issued at 106 PM CDT Fri Aug 28 2026

Starting to see some cumulus appear on visible satellite imagery
this afternoon. Temperatures have warmed up nicely into the low to
mid 90s along with upper 60s to lower 70s dewpoints. Much like
yesterday we expect showers and thunderstorms to blossom across the
area as leftover outflow boundaries and plenty of moisture remain.
Several latest Hi-Res model runs suggest this scenario
unfolding/starting within the next couple hours with most activity
waning shortly after sunset due to the loss in daytime heating. Any
storms that do form will be capable of frequent lightning, heavy
downpours and brief gusty winds in the stronger storms. However
unlike yesterday we are not expecting severe weather this afternoon
into this evening.

Drier conditions are expected overnight with forecast lows mainly in
the 70s. The ridge off to our west continues to shift eastward
tonight with dry weather expected on Saturday. Hot temperatures
continue again for Saturday (90s to around 100 degrees) and there
may be a few spots that approach or exceed advisory criteria.
However, this is expected to be brief and areal coverage should be
limited thus for those reasons we are not anticipating on issuing
any heat advisories. It will however still remain quite hot
across the area so continue to practice safe heat safety.

&&

.LONG TERM...
(Sunday through next Friday)
Issued at 106 PM CDT Fri Aug 28 2026

Mid-level ridging continues propagating eastward and should be
centered over the Southern Plains by Sunday. A disturbance in the
northern Gulf looks to make its way westward towards the Texas coast
and eventually undercuts the ridge which then allows it to
flatten/elongate towards the Middle Mississippi Valley early next
week. It's still quite a bit unclear if this disturbance will impact
our area bringing with it some rain/storm chances as models don't
have a good handle on this just yet. What is more certain is our
typical seabreeze pattern looks to make a return by Tuesday mainly
affecting areas over the Coastal Plains. For everyone else expect a
mainly dry and continued hot weather pattern to close out August and
begin the month of September.

&&

.AVIATION...
(00Z TAFS)
Issued at 615 PM CDT Fri Aug 28 2026

Isolated showers and thunderstorms may move through the terminals
over the next few hours. These storms shouldn't reduce ceilings,
but could drop visibility and produce gusty winds. Otherwise all
airports will be VFR overnight and through the day Saturday. We
do not expect any convection Saturday.

&&

.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry              76 100  76 100 /  20   0   0   0
Austin Bergstrom Intl Airport  76  99  76  99 /  20   0   0   0
New Braunfels Muni Airport     74  99  74  99 /  30   0   0   0
Burnet Muni Airport            74  97  73  97 /   0   0   0   0
Del Rio Intl Airport           77  99  77  99 /  10   0   0   0
Georgetown Muni Airport        76  99  76  99 /  10   0   0   0
Hondo Muni Airport             73  97  73  97 /  20   0   0   0
San Marcos Muni Airport        75  99  74  99 /  30   0   0   0
La Grange - Fayette Regional   76  99  76  99 /  20  10   0  10
San Antonio Intl Airport       77  98  76  98 /  30   0   0   0
Stinson Muni Airport           76 100  74 100 /  30   0   0   0

&&

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

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

In the hours before

Special weather statement, Aug 28, 6:31 PM CDT, 2 hours 38 minutes before
Special Weather Statement
National Weather Service Austin/San Antonio TX
631 PM CDT Fri Aug 28 2026

TXZ183-290015-
Val Verde TX-
631 PM CDT Fri Aug 28 2026

...A strong thunderstorm will impact portions of central Val Verde
County through 715 PM CDT...

At 631 PM CDT, Doppler radar was tracking a strong thunderstorm 10
miles east of Comstock, moving west at 20 mph.

HAZARD...Wind gusts of 50 to 55 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects.

Locations impacted include...
Comstock, Seminole Canyon State Park, Pafford Crossing, Pecos River
Boat Ramp, and Devils River State Nat Area Big Satan.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 2983 10096 2966 10089 2952 10121 2952 10125
      2962 10125 2963 10126 2962 10128 2958 10128
      2957 10129 2959 10131 2965 10130 2966 10135
      2965 10136 2970 10137 2971 10140 2973 10140
TIME...MOT...LOC 2331Z 070DEG 17KT 2972 10101

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...55 MPH

05
Special weather statement, Aug 28, 7:04 PM CDT, 2 hours 5 minutes before
Special Weather Statement
National Weather Service Austin/San Antonio TX
704 PM CDT Fri Aug 28 2026

TXZ190-191-206-290045-
Comal TX-Blanco TX-Hays TX-
704 PM CDT Fri Aug 28 2026

...A strong thunderstorm will impact portions of southwestern Hays,
south central Blanco and northeastern Comal Counties through 745 PM
CDT...

At 704 PM CDT, Doppler radar was tracking a strong thunderstorm near
Wimberley, moving west at 15 mph.

HAZARD...Wind gusts of 50 to 55 mph and half inch hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Locations impacted include...
Wimberley, Blanco, Canyon Lake Dam, Canyon Lake, Woodcreek, Spring
Branch, Smithson Valley, Twin Sisters, Fischer, Startzville, and
Sattler.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 3005 9805 2987 9804 2977 9841 2993 9842
      2994 9842 2995 9843 3009 9844
TIME...MOT...LOC 0004Z 087DEG 14KT 2996 9814

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...55 MPH

05
Special weather statement, Aug 28, 7:07 PM CDT, 2 hours 2 minutes before
Special Weather Statement
National Weather Service Austin/San Antonio TX
707 PM CDT Fri Aug 28 2026

TXZ208-290045-
Caldwell TX-
707 PM CDT Fri Aug 28 2026

...A strong thunderstorm will impact portions of central Caldwell
County through 745 PM CDT...

At 707 PM CDT, Doppler radar was tracking a strong thunderstorm near
Mustang Ridge, or 8 miles north of Lockhart, moving south at 10 mph.

HAZARD...Wind gusts of 50 to 55 mph and half inch hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Locations impacted include...
Lockhart, Martindale, Mustang Ridge, Niederwald, Brownsboro, Lytton
Springs, Dale, St John Colony, Maxwell, and Mendoza.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 2974 9756 2982 9784 2983 9784 3000 9774
      3005 9768 3003 9760 2996 9752
TIME...MOT...LOC 0007Z 018DEG 9KT 2999 9763

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...55 MPH

05
Special weather statement, Aug 28, 7:24 PM CDT, 1 hour 45 minutes before
Special Weather Statement
National Weather Service Austin/San Antonio TX
724 PM CDT Fri Aug 28 2026

TXZ191-206-207-290115-
Guadalupe TX-Comal TX-Hays TX-
724 PM CDT Fri Aug 28 2026

...A strong thunderstorm will impact portions of south central Hays,
central Guadalupe and southeastern Comal Counties through 815 PM
CDT...

At 724 PM CDT, Doppler radar was tracking a strong thunderstorm 7
miles northwest of Zorn, or 7 miles southwest of San Marcos, moving
southwest at 10 mph.

HAZARD...Wind gusts of 50 to 55 mph and half inch hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Locations impacted include...
New Braunfels, San Marcos, Schertz, Seguin, Canyon Lake, McQueeney,
Geronimo, Zorn, Hunter, Freiheit, Solms, Gruene, New Braunfels
National Airport, and Redwood.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 2989 9805 2985 9792 2957 9798 2969 9830
      2984 9817 2987 9807
TIME...MOT...LOC 0024Z 027DEG 9KT 2981 9805

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...55 MPH

05
Special weather statement, Aug 28, 8:16 PM CDT, 53 minutes before
Special Weather Statement
National Weather Service Austin/San Antonio TX
816 PM CDT Fri Aug 28 2026

TXZ205>207-221-290200-
Guadalupe TX-Comal TX-Bexar TX-Wilson TX-
816 PM CDT Fri Aug 28 2026

...Strong thunderstorms will impact portions of southwestern
Guadalupe, northern Wilson, northern Bexar and southwestern Comal
Counties through 900 PM CDT...

At 816 PM CDT, Doppler radar was tracking strong thunderstorms along
a line extending from near Timberwood Park to Seguin. Movement was
southwest at 20 mph.

HAZARD...Wind gusts of 50 to 55 mph and half inch hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Locations impacted include...
San Antonio, New Braunfels, Schertz, Seguin, Cibolo, Converse,
Universal City, Live Oak, Selma, San Antonio Int Airport, Randolph
AFB, Leon Valley, Helotes, Fair Oaks Ranch, Kirby, Alamo Heights,
Windcrest, Terrell Hills, Garden Ridge, and Shavano Park.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 2948 9880 2965 9881 2977 9858 2961 9784
      2932 9813
TIME...MOT...LOC 0116Z 053DEG 18KT 2972 9855 2960 9798

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...55 MPH

05
Special weather statement, Aug 28, 8:26 PM CDT, 43 minutes before
Special Weather Statement
National Weather Service Austin/San Antonio TX
826 PM CDT Fri Aug 28 2026

TXZ204-205-290215-
Bexar TX-Medina TX-
826 PM CDT Fri Aug 28 2026

...A strong thunderstorm will impact portions of southeastern Medina
and west central Bexar Counties through 915 PM CDT...

At 826 PM CDT, Doppler radar was tracking a strong thunderstorm near
Castroville, moving west at 20 mph.

HAZARD...Wind gusts of 50 to 55 mph and half inch hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Locations impacted include...
Hondo, Castroville, Lacoste, Biry, Pearson, Noonan, New Fountain,
Quihi, Dunlay, Rio Medina, Bader, and Macdona.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 2950 9876 2933 9869 2916 9911 2941 9921
TIME...MOT...LOC 0126Z 071DEG 18KT 2939 9881

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...55 MPH

05

The office that day

Everything else NWS Austin/San Antonio, TX issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 28, 7:04 PM CDTSpecial Weather StatementEWXComal41 min
Aug 28, 7:07 PM CDTSpecial Weather StatementEWXCaldwell38 min
Aug 28, 7:24 PM CDTSpecial Weather StatementEWXComal51 min
Aug 28, 8:16 PM CDTSpecial Weather StatementEWXBexar, Guadalupe44 min
Aug 28, 8:26 PM CDTSpecial Weather StatementEWXMedina49 min
Aug 28, 8:49 PM CDTAreal Flood AdvisoryEWXBexar, Comal, Guadalupe, Hays3 hr
Aug 28, 9:13 PM CDTSevere Thunderstorm WarningEWXAtascosa, Bexar, Medina62 min

Nearby

Flash Flood Warnings in Texas, 2026Every flash flood warning in 2026

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.