Alert archive / Texas / Flash Flood Warnings in 2004

Flash Flood Warning 264, NWS Austin/San Antonio, TX

August 19, 2004Williamson County, Texas

NWS Austin/San Antonio, TX issued this flash flood warning at Aug 19, 2004, 11:11 PM CDT for Williamson 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
Aug 19, 2004, 11:11 PM CDT (04:11 UTC)
Expired
Aug 20, 2004, 2:15 AM CDT
In force
3 hr
Issued by
NWS Austin/San Antonio, TX
Area
Counties, with a storm outline in the text

County Williamson County, TX

The nearest sounding before it

Fort Worth, TX (KFWD), launched 00:00Z, 4.2 hours before the alert went out and 254 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, Fort Worth, TX at 00:00Z on 2004-08-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 732 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, Fort Worth, TX at 00:00Z on 2004-08-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 125 square meters per square second.193958Sfc1 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
732 J/kg
Mixed-layer CIN
-94 J/kg
Mixed-layer LCL
814 m above ground
0-6 km bulk shear
35 kt
0-1 km storm-relative helicity
125 m²/s²
0-3 km storm-relative helicity
153 m²/s²
Significant tornado parameter
0.3
Supercell composite
2.8

Open this sounding in Storm Lab

The text

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

000 
WGUS54 KEWX 200413
FFWSAT
TXC491-200715-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
1111 PM CDT THU AUG 19 2004

THE NATIONAL WEATHER SERVICE IN AUSTIN SAN ANTONIO HAS ISSUED A

* FLASH FLOOD WARNING FOR THE FOLLOWING COUNTIES...
  WILLIAMSON

* UNTIL 215 AM CDT

* AT 1100 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR 
  INDICATED FLASH FLOODING FROM A THUNDERSTORM ABOUT OVER CEDAR      
  PARK...MOVING EAST AT 15 MPH.

* OTHER LOCATIONS IN THE WARNING INCLUDE WEIR...THRALL...TAYLOR...
  SERENADA...LIBERTY HILL...HUTTO...GRANGER DAM...GRANGER...
  GEORGETOWN DAM...GEORGETOWN...FLORENCE...COUPLAND AND ANDICE.

EXCESSIVE RUNOFF FROM THIS STORM WILL CAUSE FLASH FLOODING OF CREEKS
AND STREAMS...ROADS AND ROADSIDE CULVERTS. THE HEAVY RAINS COULD ALSO
TRIGGER ROCK SLIDES IN STEEP TERRAIN.   2 TO 4 INCHES OF RAIN HAVE 
ALREADY FALLEN ACROSS MOST OF WILLIAMSON COUNTY TONIGHT.

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.

LAT...LON 3042 9732 3041 9734 3049 9750 3048 9754
      3051 9759 3050 9764 3059 9792 3064 9795
      3088 9785 3073 9727 3056 9721

$$
2 follow-up statements
000 
WGUS74 KEWX 200447
FFSSAT
TXC491-200715-

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
1143 PM CDT THU AUG 19 2004

...A FLASH FLOOD WARNING CONTINUES UNTIL 215 AM CDT FOR WILLIAMSON
COUNTY...

AT 1135 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO 
INDICATE HEAVY RAIN BETWEEN ROUND ROCK AND LEANDER...MOVING EAST AT 
15 MPH.  A LARGE AREA OF THE COUNTY...FROM  LEANDER TO SERENADA TO 
BARTLETT AND GRANGER DAM...HAS RECEIVED 2 TO 4 INCHES OF RAIN OVER 
THE PAST 3 HOURS.

OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO WEIR...
THRALL...TAYLOR...SERENADA...LIBERTY HILL...JARRELL...GRANGER DAM...
GRANGER...GEORGETOWN DAM...GEORGETOWN...FLORENCE...COUPLAND AND
ANDICE.

A FLASH FLOOD WARNING MEANS THAT FLOODING IS IMMINENT OR OCCURRING.
IF YOU ARE IN THE WARNING AREA MOVE TO HIGHER GROUND IMMEDIATELY.
RESIDENTS LIVING ALONG STREAMS AND CREEKS SHOULD TAKE IMMEDIATE
PRECAUTIONS TO PROTECT LIFE AND PROPERTY. DO NOT ATTEMPT TO CROSS
SWIFTLY FLOWING WATERS OR WATERS OF UNKNOWN DEPTH BY FOOT OR BY
AUTOMOBILE.

TO REPORT FLOODING...HAVE THE NEAREST LAW ENFORCEMENT AGENCY RELAY
YOUR REPORT TO THE NATIONAL WEATHER SERVICE FORECAST OFFICE IN AUSTIN
SAN ANTONIO.

LAT...LON 3042 9732 3041 9734 3049 9750 3048 9754
      3051 9759 3050 9764 3059 9792 3064 9795
      3088 9785 3073 9727 3056 9721

$$
000 
WGUS74 KEWX 200609
FFSSAT
TXC491-200715-

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
107 AM CDT FRI AUG 20 2004

...A FLASH FLOOD WARNING CONTINUES UNTIL 215 AM CDT FOR WILLIAMSON
COUNTY...

AT 102 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED 
ONLY LIGHT RAIN ACROSS WILLIAMSON COUNTY. SMALL STREAMS MAY CONTINUE 
TO RUN HIGH AND IN FLOOD FOR THE NEXT HOUR FROM EARLIER RAINS.

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL 
CREEKS AND STREAMS...URBAN AREAS...HIGHWAYS...STREETS AND UNDERPASSES
AS WELL AS OTHER DRAINAGE AREAS AND LOW LYING SPOTS.

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE
DANGERS OF FLOODING. 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.

LAT...LON 3042 9732 3041 9734 3049 9750 3048 9754
      3051 9759 3050 9764 3059 9792 3064 9795
      3088 9785 3073 9727 3056 9721

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 19, 9:17 PM CDTSevere Thunderstorm WarningEWXTravis, Williamson58 min
Aug 19, 9:35 PM CDTFlash Flood WarningEWXWilliamson115 min
Aug 19, 10:34 PM CDTSevere Thunderstorm WarningEWXTravis56 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.