Alert archive / Texas / Flash Flood Warnings in 2004

Flash Flood Warning 70, NWS Austin/San Antonio, TX

April 24, 2004Comal County, Texas

NWS Austin/San Antonio, TX issued this flash flood warning at Apr 24, 2004, 2:15 AM CDT for Comal County, Texas. It was in force for 3 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Apr 24, 2004, 2:15 AM CDT (07:15 UTC)
Expired
Apr 24, 2004, 5:15 AM CDT
In force
3 hr
Issued by
NWS Austin/San Antonio, TX
Area
Counties, with a storm outline in the text

County Comal County, TX

The radar

The Austin/San Antonio radar (KEWX), 34 km from the middle of the area, began a volume at 07:17 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.

The nearest sounding before it

Del Rio, TX (KDRT), launched 00:00Z, 7.3 hours before the alert went out and 244 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, Del Rio, TX at 00:00Z on 2004-04-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2594 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Del Rio, TX at 00:00Z on 2004-04-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -15 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
2594 J/kg
Mixed-layer CIN
-20 J/kg
Mixed-layer LCL
842 m above ground
0-6 km bulk shear
18 kt
0-1 km storm-relative helicity
-15 m²/s²
0-3 km storm-relative helicity
-34 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
WGUS54 KEWX 240715
FFWSAT
TXC091-241015-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
215 AM CDT SAT APR 24 2004

THE NATIONAL WEATHER SERVICE IN AUSTIN SAN ANTONIO HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  COMAL COUNTY IN SOUTH CENTRAL TEXAS
  THIS INCLUDES THE CITY OF CANYON LAKE DAM

* UNTIL 515 AM CDT

* AT 210 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  FLASH FLOODING FROM A THUNDERSTORM NEAR SMITHSON VALLEY...OR ABOUT
  7 MILES SOUTH OF CANYON LAKE DAM...MOVING NORTHEAST AT 20 MPH.

* OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
  SPRING BRANCH...GARDEN RIDGE AND FISCHER.

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE
DANGERS OF FLOODS AND FLASH FLOODS. IF FLASH FLOODING IS OBSERVED ACT
QUICKLY. MOVE UP TO HIGHER GROUND TO ESCAPE FLOOD WATERS. DO NOT STAY
IN AREAS SUBJECT TO FLOODING WHEN WATER BEGINS RISING.

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE
ROADWAY. THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS
SAFELY. VEHICLES CAUGHT IN RISING WATER SHOULD BE ABANDONED QUICKLY.
MOVE TO HIGHER GROUND.

LAT...LON 2981 9858 2977 9836 2962 9831 2978 9804
          3002 9830

$$

LENZ
1 follow-up statement
000 
WGUS74 KEWX 240931
FFSSAT
TXC091-241015-

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
430 AM CDT SAT APR 24 2004

...THE FLASH FLOOD WARNING FOR COMAL COUNTY IS CANCELLED...

AT 430 AM CDT...DOPPLER RADAR INDICATED THAT THE HEAVY RAIN HAD 
MOVED EAST AND NORTH OF COMAL COUNTY WITH ONLY LIGHT RAIN 
CONTINUING. PONDING OF WATER ON ROADS WILL CONTINUE FOR THE NEXT 
SEVERAL HOURS.

LAT...LON 2981 9858 2977 9836 2962 9831 2978 9804
          3002 9830

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 23, 9:38 PM CDTTornado WarningEWXMaverick37 min
Apr 24, 12:50 AM CDTSevere Thunderstorm WarningEWXMedina25 min
Apr 24, 12:54 AM CDTSevere Thunderstorm WarningEWXBexar51 min
Apr 24, 1:10 AM CDTFlash Flood WarningEWXAtascosa, Bexar3 hr
Apr 24, 1:15 AM CDTSevere Thunderstorm WarningEWXAtascosa45 min
Apr 24, 1:30 AM CDTSevere Thunderstorm WarningEWXKendall45 min
Apr 24, 1:42 AM CDTSevere Thunderstorm WarningEWXWilson48 min
Apr 24, 2:08 AM CDTFlash Flood WarningEWXBlanco, Gillespie3 hr
Apr 24, 2:10 AM CDTSevere Thunderstorm WarningEWXComal, Guadalupe50 min
Apr 24, 2:46 AM CDTFlash Flood WarningEWXGonzales, Guadalupe3 hr
Apr 24, 3:42 AM CDTSevere Thunderstorm WarningEWXLavaca63 min

Nearby

Flash Flood Warnings in Texas, 2004Every flash flood warning in 2004

Sources

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