Alert archive / Texas / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 57, NWS Austin/San Antonio, TX

February 18, 1998Atascosa County, Texas

NWS Austin/San Antonio, TX issued this severe thunderstorm warning at Feb 18, 1998, 5:47 PM CST for Atascosa 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
Feb 18, 1998, 5:47 PM CST (23:47 UTC)
Expired
Feb 18, 1998, 6:45 PM CST
In force
58 min
Issued by
NWS Austin/San Antonio, TX
Area
Whole counties

County Atascosa County, TX

The radar

The Austin/San Antonio radar (KEWX), 102 km from the middle of the area, began a volume at 23:50 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
Feb 18, 5:50 PM CSTHail 1Campbellton, TX
Feb 18, 6:38 PM CSTHail 0.75Campbellton, 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

Del Rio, TX (KDRT), launched 12:00Z, 11.8 hours before the alert went out and 231 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 1998-02-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 1998-02-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 348 square meters per square second.1939587897Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1649 m above ground
0-6 km bulk shear
79 kt
0-1 km storm-relative helicity
348 m²/s²
0-3 km storm-relative helicity
450 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.

062 
WUUS1 KSAT 182348
SVRSAT
TXC013-190045-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
547 PM CST WED FEB 18 1998
 
THE NATIONAL WEATHER SERVICE IN AUSTIN/SAN ANTONIO HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  645 PM CST
FOR PEOPLE IN THE FOLLOWING LOCATION...
 
IN SOUTH CENTRAL TEXAS
 
   ...ATASCOSA COUNTY
 
AT 6:45 PM...RADAR CONTINUED TO INDICATE A SEVERE THUNDERSTORM IN
JOURDANTON MOVING EAST NEAR 15 MPH. THIS STORM HAS A HISTORY OF
PRODUCING GOLFBALL SIZE HAIL.
 
PEOPLE IN THE PATH OF THIS STORM SHOULD BE ALERT TO THE POSSIBILITY
OF LARGE HAIL AND DAMAGING WINDS.  FREQUENT LIGHTNING AND LOCALLY
HEAVY RAIN CAN ALSO OCCUR WITH SEVERE THUNDERSTORMS...FLOODING SMALL
STREAMS...LOW AREAS...AND LOW WATER CROSSINGS.
 
 
 
&

The office that day

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

IssuedProductOfficeCountiesLasted
Feb 18, 4:36 PM CSTSevere Thunderstorm WarningEWXFrio54 min
Feb 18, 4:48 PM CSTSevere Thunderstorm WarningEWXAtascosa57 min
Feb 18, 5:01 PM CSTSevere Thunderstorm WarningEWXBexar59 min
Feb 18, 5:33 PM CSTSevere Thunderstorm WarningEWXWilson57 min

Nearby

Severe Thunderstorm Warnings in Texas, 1998Every severe thunderstorm warning in 1998

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; radar from the NEXRAD Level II archive.