Alert archive / Texas / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 45, NWS Austin/San Antonio, TX

April 20, 1997Travis County, Texas

NWS Austin/San Antonio, TX issued this severe thunderstorm warning at Apr 20, 1997, 9:17 PM CDT for Travis County, Texas. It was in force for 58 min. 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
Apr 20, 1997, 9:17 PM CDT (02:17 UTC)
Expired
Apr 20, 1997, 10:15 PM CDT
In force
58 min
Issued by
NWS Austin/San Antonio, TX
Area
Whole counties

County Travis County, TX

What was reported inside it

TimeReportWhereRemark
Apr 20, 10:10 PM CDTThunderstorm Wind 69Lake Travis, TX
Apr 20, 10:24 PM CDTThunderstorm Wind 62Lake Travis, TX

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.

The nearest sounding before it

Fort Worth, TX (KFWD), launched 00:00Z, 2.3 hours before the alert went out and 281 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 1997-04-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 406 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Fort Worth, TX at 00:00Z on 1997-04-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 114 square meters per square second.193958Sfc1 km3 km6 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
406 J/kg
Mixed-layer CIN
-150 J/kg
Mixed-layer LCL
1725 m above ground
0-6 km bulk shear
38 kt
0-1 km storm-relative helicity
114 m²/s²
0-3 km storm-relative helicity
277 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 210219 RRA
SVRSAT
TXC453-210315-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
917 PM CDT SUN APR 20 1997
 
THE NATIONAL WEATHER SERVICE IN AUSTIN/SAN ANTONIO HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 1015 PM CDT
FOR PEOPLE IN THE FOLLOWING LOCATION...
 
IN SOUTH CENTRAL TEXAS
 
   ...TRAVIS COUNTY
 
AT 917 PM CDT WEATHER RADAR INDICATED A LINE OF THUNDERSTORMS WITH
DAMAGING WIND MOVING EASTWARD AT 40 MPH INTO WESTERN TRAVIS COUNTY.
RESIDENTS OF AUSTIN SHOULD TAKE COVER WITH THE APPROACH OF THESE STORMS.
 
SEVERE THUNDERSTORM WINDS CAN REACH SPEEDS OVER 60 MPH.  THESE WINDS
BLOW DOWN TREES...POWER LINES...AND SEVERELY DAMAGE MOBILE HOMES...
SOMETIMES BUILDINGS.  VERY LARGE HAIL CAN INJURE ANYONE CAUGHT
OUTSIDE.
 
REPORT INCIDENTS OF SEVERE WEATHER TO LOCAL LAW ENFORCEMENT FOR RELAY TO
THE NATIONAL WEATHER SERVICE.

What forecasters said that day

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

In the hours before

Special weather statement, Apr 20, 5:35 PM CDT, 3 hours 42 minutes before
TXZ171>173-183>194-202>209-217>225-228-211200-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
535 PM CDT SUN APR 20 1997

THE STORM PREDICTION CENTER IN NORMAN OK HAS ISSUED A SEVERE
THUNDERSTORM WATCH FOR THE ENTIRE TEXAS HILL COUNTRY AND ADJOINING
PORTIONS OF SOUTH CENTRAL TEXAS.

A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE FAVORABLE FOR THE
DEVELOPMENT OF SEVERE THUNDERSTORMS WITH LARGE HAIL AND DAMAGINGS
WINDS.

THE WATCH IS ALONG AND NORTH OF A LINE FROM DEL RIO TO UVALDE...
HONDO... SAN ANTONIO... NEW BRAUNFELS... SAN MARCOS... AUSTIN... AND
GEORGETOWN.

THE ATMOSPHERE HAS BECOME VERY UNSTABLE WITH INCREASING HUMIDITY AND
WARM TEMPERATURES ACROSS SOUTH AND CENTRAL TEXAS.  A WEAK UPPER LEVEL
DISTURBANCE WILL MOVE THROUGH CENTRAL TEXAS THIS EVENING.
THUNDERSTORMS WILL CONTINUE TO DEVELOP ALONG THE DISTURBANCE.

THE HAZARDOUS WEATHER OUTLOOK WILL NORMALLY BE UPDATED BY MEANS OF
THE ZONE FORECAST...SHORT TERM FORECASTS...WATCHES....WARNINGS AND
ADVISORIES.  THE HAZARDOUS WEATHER OUTLOOK ITSELF WILL BE UPDATED
ONLY IF UNFORECAST HAZARDOUS WEATHER DEVELOPS OR IF FORECAST
HAZARDOUS WEATHER IS NO LONGER EXPECTED.
Special weather statement, Apr 20, 5:44 PM CDT, 3 hours 33 minutes before
TXZ171>173-183>194-202>209-217>225-228-211200-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
535 PM CDT SUN APR 20 1997

THE STORM PREDICTION CENTER IN NORMAN OK HAS ISSUED A SEVERE
THUNDERSTORM WATCH FOR THE ENTIRE TEXAS HILL COUNTRY AND ADJOINING
PORTIONS OF SOUTH CENTRAL TEXAS.

A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE FAVORABLE FOR THE
DEVELOPMENT OF SEVERE THUNDERSTORMS WITH LARGE HAIL AND DAMAGINGS
WINDS.

THE WATCH IS ALONG AND NORTH OF A LINE FROM DEL RIO TO UVALDE...
HONDO... SAN ANTONIO... NEW BRAUNFELS... SAN MARCOS... AUSTIN... AND
GEORGETOWN.

THE ATMOSPHERE HAS BECOME VERY UNSTABLE WITH INCREASING HUMIDITY AND
WARM TEMPERATURES ACROSS SOUTH AND CENTRAL TEXAS.  A WEAK UPPER LEVEL
DISTURBANCE WILL MOVE THROUGH CENTRAL TEXAS THIS EVENING.
THUNDERSTORMS WILL CONTINUE TO DEVELOP ALONG THE DISTURBANCE.

THE HAZARDOUS WEATHER OUTLOOK WILL NORMALLY BE UPDATED BY MEANS OF
THE ZONE FORECAbST...SHORT TERM FORECASTS...WATCHES....WARNINGS AND
ADVISORIES.  THE HAZARDOUS WEATHER OUTLOOK ITSELF WILL BE UPDATED
ONLY IF UNFORECAST HAZARDOUS WEATHER DEVELOPS OR IF FORECAST
HAZARDOUS WEATHER IS NO LONGER EXPECTED.

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 20, 8:07 PM CDTSevere Thunderstorm WarningEWXBurnet, Llano53 min
Apr 20, 8:57 PM CDTSevere Thunderstorm WarningEWXBlanco, Comal, Hays, Kendall63 min
Apr 20, 9:31 PM CDTSevere Thunderstorm WarningEWXWilliamson44 min
Apr 20, 10:14 PM CDTSevere Thunderstorm WarningEWXGuadalupe46 min
Apr 20, 11:17 PM CDTSevere Thunderstorm WarningEWXLavaca43 min
Apr 21, 3:47 AM CDTSevere Thunderstorm WarningEWXBastrop, Travis, Williamson58 min

Nearby

Severe Thunderstorm Warnings in Texas, 1997Every severe thunderstorm warning in 1997

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive.