Alert archive / Texas / Flash Flood Warnings in 2007

Flash Flood Warning 337, NWS Austin/San Antonio, TX

July 7, 2007Williamson County, Texas

NWS Austin/San Antonio, TX issued this flash flood warning at Jul 7, 2007, 8:04 PM CDT for Williamson County, Texas. It was in force for 2 hr. 2 reports came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued
Jul 7, 2007, 8:04 PM CDT (01:04 UTC)
Expired
Jul 7, 2007, 10:15 PM CDT
In force
2 hr
Issued by
NWS Austin/San Antonio, TX
Area
Whole counties

County Williamson County, TX

The radar

The Ft Hood radar (KGRK), 22 km from the middle of the area, began a volume at 01:08 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
Jul 7, 8:10 PM CDTFLASH FLOODGeorgetown, TXCOUNTY ROAD 100 CLOSED.
Jul 7, 8:10 PM CDTFLASH FLOODLiberty Hill, TXCOUNTY ROAD 214 CLOSED.

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

The nearest sounding before it

Fort Worth, TX (KFWD), launched 00:00Z, 1.1 hours before the alert went out and 245 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 2007-07-08Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1133 joules per kilogram.LCLEL10008507005003002001001 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 2007-07-08The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 0 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
1133 J/kg
Mixed-layer CIN
-3 J/kg
Mixed-layer LCL
1761 m above ground
0-6 km bulk shear
7 kt
0-1 km storm-relative helicity
0 m²/s²
0-3 km storm-relative helicity
7 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 080105
FFWEWX
TXC491-080315-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
804 PM CDT SAT JUL 7 2007

THE NATIONAL WEATHER SERVICE IN AUSTIN SAN ANTONIO HAS EXTENDED THE

* FLASH FLOOD WARNING FOR...
  WILLIAMSON COUNTY IN SOUTH CENTRAL TEXAS...
  THIS INCLUDES THE CITIES OF...SERENADA...GEORGETOWN...

* UNTIL 1015 PM CDT

* AT 800 PM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS CONTINUED 
  TO DETECT THUNDERSTORMS PRODUCING VERY HEAVY RAIN. THESE STORMS
  WERE LOCATED ALONG A LINE EXTENDING FROM 5 MILES WEST OF LIBERTY
  HILL TO LIBERTY HILL TO GEORGETOWN TO HUTTO WHILE OTHER STORMS 
  SOUTHWEST OF CEDAR PARK AND LIBERTY HILL MOVE INTO THE LINE. 
  RAINFALL RATES OF 2 TO 4 INCHES PER HOUR WERE NOTED. THESE RAINS
  CAUSE RISES OUT OF BANKS AND POSSIBLY INTO FLOOD ALONG THE SOUTH
  AND MIDDLE FORKS OF THE SAN GABRIEL RIVER AND THEIR TRIBUTARIES
  IN AND WEST OF GEORGETOWN INCLUDING HIGHWAY 29 AND FM 2338.

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO LIBERTY
  HILL...WEIR AND GEORGETOWN DAM

RUNOFF FROM HEAVY RAIN WILL FLOOD CREEKS, STREAMS, STREET
INTERSECTIONS, CULVERTS AND UNDERPASSES. LOW LYING PLACES THAT
NORMALLY FLOOD COULD BECOME DEATH TRAPS. DO NOT CROSS ANY FLOODED
AREA. TURN AROUND DONT DROWN.

WHEN WATER COVERS THE ROAD...TURN AROUND DONT DROWN. THE LIFE YOU
SAVE MAY BE YOUR OWN.

LAT...LON 3052 9783 3054 9754 3075 9753 3077 9798
      3067 9801

$$
2 follow-up statements
000 
WGUS74 KEWX 080140
FFSEWX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
839 PM CDT SAT JUL 7 2007

TXC491-080315-
WILLIAMSON TX-
839 PM CDT SAT JUL 7 2007

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1015 PM CDT FOR
WILLIAMSON COUNTY...

AT 832 PM CDT...NATIONAL WEATHER SERVICE RADAR SHOWED RAINS RAPIDLY 
WEAKENING ACROSS WILLIAMSON COUNTY. HIGHEST RAINFALL RATES WERE NOW 
NEAR ONE QUARTER INCH PER HOUR. HOWEVER...EARLIER VERY HEAVY RAINS 
UP TO 5 INCHES WILL CAUSE CONTINUED RISES OUT OF BANKS AND POSSIBLY 
INTO FLOOD ALONG THE SOUTH AND MIDDLE FORKS OF THE SAN GABRIEL RIVER 
AND THEIR TRIBUTARIES IN AND WEST OF GEORGETOWN. THIS WILL IMPACT 
AREAS ALONG HIGHWAY 29 AND FM 2338.

LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO LIBERTY 
HILL...WEIR...SERENADA AND GEORGETOWN DAM

RUNOFF FROM HEAVY RAIN WILL FLOOD CREEKS, STREAMS, STREET
INTERSECTIONS, CULVERTS AND UNDERPASSES. LOW LYING PLACES THAT
NORMALLY FLOOD COULD BECOME DEATH TRAPS. DO NOT CROSS ANY FLOODED
AREA. TURN AROUND DONT DROWN.

WHEN WATER COVERS THE ROAD...TURN AROUND DONT DROWN. THE LIFE YOU
SAVE MAY BE YOUR OWN.

WITH SUNSET APPROACHING...IT IS HARD TO RECOGNIZE THE DANGERS OF 
FLOODING AT NIGHT. IF FLOOD WATERS RISE ACT QUICKLY. DO NOT STAY IN 
FLOOD PRONE AREAS.

LAT...LON 3052 9783 3054 9754 3075 9753 3077 9798
      3067 9801

$$
000 
WGUS74 KEWX 080325
FFSEWX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
1022 PM CDT SAT JUL 7 2007

TXC491-080332-
WILLIAMSON TX-
1022 PM CDT SAT JUL 7 2007

...THE FLASH FLOOD WARNING HAS EXPIRED FOR WILLIAMSON COUNTY...

AT 1015 PM CDT...NATIONAL WEATHER SERVICE RADAR SHOWED THE RAINS 
HAVE ENDED ACROSS WILLIAMSON COUNTY. THE THREAT FOR FLASH FLOODING 
HAS ENDED. AS A RESULT...THE FLASH FLOOD WARNING WAS ALLOWED TO 
EXPIRE. HOWEVER...SOME RIVERS AND CREEKS WILL REMAIN OUT OF BANKS 
AND LOW LYING AREAS WILL EXPERIENCE PONDING OF WATER THE NEXT FEW 
HOURS DUE TO THE EARLIER VERY HEAVY RAINS UP TO 6 INCHES. SEE 
HYDROLOGIC STATEMENTS FOR DETAILS.

LAT...LON 3052 9783 3054 9754 3075 9753 3077 9798
      3067 9801

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 8, 6:45 AM CDTFlash Flood WarningEWXBandera, Real, Uvalde4 hr
Jul 8, 2:38 PM CDTRiver Flood WarningEWXKarnes18 hr

Nearby

Flash Flood Warnings in Texas, 2007Every flash flood warning in 2007

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.