Alert archive / Texas / Flash Flood Warnings in 1999

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

August 23, 1999Atascosa County, Frio County, Texas

NWS Austin/San Antonio, TX issued this flash flood warning at Aug 23, 1999, 12:30 PM CDT for Atascosa County, Frio County, Texas. It was in force for 4 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Aug 23, 1999, 12:30 PM CDT (17:30 UTC)
Expired
Aug 23, 1999, 4:00 PM CDT
In force
4 hr
Issued by
NWS Austin/San Antonio, TX
Area
Whole counties

Counties Atascosa County, TX, Frio County, TX

The radar

The Austin/San Antonio radar (KEWX), 119 km from the middle of the area, began a volume at 17:31 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 12:00Z, 5.5 hours before the alert went out and 204 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 12:00Z on 1999-08-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1607 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, Del Rio, TX at 12:00Z on 1999-08-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 25 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
1607 J/kg
Mixed-layer CIN
-41 J/kg
Mixed-layer LCL
996 m above ground
0-6 km bulk shear
25 kt
0-1 km storm-relative helicity
25 m²/s²
0-3 km storm-relative helicity
92 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.6

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KSAT 231729
FFWSAT
TXC013-163-232100-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
1230 PM CDT MON AUG 23 1999

THE NATIONAL WEATHER SERVICE IN AUSTIN/SAN ANTONIO HAS
EXTENDED THE

* FLASH FLOOD WARNING FOR...
  ATASCOSA COUNTY IN TEXAS
  FRIO COUNTY IN TEXAS

* UNTIL 400 PM CDT

* AT 1230 PM ... NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  BANDS OF THUNDERSTORMS ASSOCIATED WITH TROPICAL STORM BRET
  MOVING EAST TO WEST ACROSS CENTRAL ATASCOSA AND CENTRAL FRIO
  COUNTIES.  RAINFALL RATES WERE 2 TO 4 INCHES PER HOUR WITH THE
  HEAVIEST RAINS EAST OF PEARSALL TO CHARLOTTE.

 MOTORISTS SHOULD BE ALTERT TO POSSIBLE FLOODING ALONG STATE
 HIGHWAYS 85 AND 97. DON'T DRIVE ACROSS FLOODED ROADS! MOST FLASH
 FLOOD DEATHS OCCUR IN AUTOMOBILES.


AREA RESIDENTS SHOULD MONITOR FLOOD CONDITIONS... AND BE PREPARED
TO MOVE TO HIGHER GROUND... SHOULD FLOOD WATERS THREATEN. IF FLASH
FLOODING IS OBS`ERVED... ACT QUICKLY. MOVE TO HIGHER GROUND TO
ESCAPE FLOOD WATERS. DO NOT STAY IN AREAS SUBJECT TO FLOODING WHEN
WATER BEGINS RISING.

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 23, 9:25 AM CDT, 3 hours 5 minutes earlier.

Area forecast discussion, Aug 23, 9:25 AM CDT, 3 hours 5 minutes before
SOUTH CENTRAL TEXAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
925 AM CDT MON AUG 23 1999

WILL ADJUST FFA ONE TIER OF COUNTIES SLIGHTLY FURTHER NORTH AND
CANCEL FOR FAYETTE COUNTY.  HEAVY RAIN BANDS ARE PUSHING A BIT
FURTHER NORTH DUE TO SLIGHTLY MORE NRLY TRACK OF BRET OVER THE PAST
FEW HOURS. MAY ALSO ADJUST MAX TEMPS DOWN IN THE RAIN AREAS AS
LIMITED WARMING EXPECTED DURING THE DAY. WILL LIKELY HAVE TO EXTEND
WATCH OVER THE WRN CWA ON AFTERNOON PACKAGE.  REST OF FORECAST LOOKS
FINE.

.EWX...FLASH FLOOD WATCH THRU THIS EVENING SRN SXNS S CENTRAL TX.
       TORNADO WATCH UNTIL 4PM ATASCOSA KARNES AND FRIO COUNTIES

01/04

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 23, 7:22 AM CDTFlash Flood WarningEWXAtascosa, Frio5 hr
Aug 23, 7:51 AM CDTFlash Flood WarningEWXKarnes4 hr
Aug 23, 11:59 AM CDTFlash Flood WarningEWXDeWitt3 hr
Aug 23, 4:20 PM CDTTornado WarningEWXBurnet, Williamson45 min

Nearby

Flash Flood Warnings in Texas, 1999Every flash flood warning in 1999

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.