Alert archive / Texas / Severe Thunderstorm Warnings in 1990

Severe Thunderstorm Warning 37, NWS Austin/San Antonio, TX

May 20, 1990McMullen County, Texas

NWS Austin/San Antonio, TX issued this severe thunderstorm warning at May 20, 1990, 8:02 PM CDT for McMullen County, Texas. It was in force for 58 min.

The area

The counties it named.

The facts

Issued
May 20, 1990, 8:02 PM CDT (01:02 UTC)
Expired
May 20, 1990, 9:00 PM CDT
In force
58 min
Issued by
NWS Austin/San Antonio, TX
Area
Whole counties

County McMullen County, TX

The radar

The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.

The nearest sounding before it

Corpus Christi, TX (KCRP), launched 00:00Z, 1.0 hours before the alert went out and 139 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, Corpus Christi, TX at 00:00Z on 1990-05-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3978 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, Corpus Christi, TX at 00:00Z on 1990-05-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 79 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
3978 J/kg
Mixed-layer CIN
-197 J/kg
Mixed-layer LCL
1074 m above ground
0-6 km bulk shear
44 kt
0-1 km storm-relative helicity
79 m²/s²
0-3 km storm-relative helicity
93 m²/s²
Significant tornado parameter
0.0
Supercell composite
4.1

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KSAT 210103
SVRSAT
TXC311-210200-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE SAN ANTONIO TX
802 PM CDT SUN MAY 20 1990
 
THE NATIONAL WEATHER SERVICE IN SAN ANTONIO HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  900 PM CDT
FOR PEOPLE IN THE FOLLOWING COUNTY...
 
IN SOUTH TEXAS
          ...MCMULLEN
 
A SEVERE THUNDERSTORM WAS INDICATED IN EXTREME WESTERN MCMULLEN COUNTY
JUST TO THE WEST OF TILDEN AT 800 PM THIS EVENING. THIS STORM LIKELY
HAS LARGE HAIL AND MAY PRODUCE DAMAGING WINDS AS WELL. THE STORM IS
MOVING TO THE NORTHEAST AT 20 MPH.
 
 
SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 55 MPH...HAIL
3/4 INCH OR MORE IN DIAMETER...FREQUENT LIGHTNING AND VERY HEAVY
RAIN.

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, May 20, 4:45 PM CDT, 3 hours 17 minutes before
TXZ035-040-202240-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SAN ANTONIO, TX
445 PM CDT SUN MAY 20 1990

AT 440 PM THIS AFTERNOON...NATIONAL WEATHER SERVICE RADAR INDICATED A
THUNDERSTORM WITH VERY HEAVY RAIN IN MEXICO...APPROXIMATELY 15 MILES
SOUTHWEST OF THE CITY OF LAREDO.  THE THUNDERSTORM WAS MOVING TO THE
NORTHEAST AT 10 MPH.

BECAUSE THE ATMOSPHERE IS VERY UNSTABLE THIS AFTERNOON...AND BECAUSE
OF AFTERNOON TEMPERATURES WELL OVER 100 DEGREES IN THE LAREDO AREA...
THIS STORM ALSO HAS THE POTENTIAL OF PRODUCING VERY STRONG AND POSSIBLY
DAMAGING WINDS.  IF THE STORM CONTINUES TO MOVE AT ITS CURRENTLY
DIRECTION AND SPEED IT WILL REACH THE CITY OF LAREDO NEAR 600 PM THIS
EVENING.
Special weather statement, May 20, 5:36 PM CDT, 2 hours 26 minutes before
TXZ035-040-202340-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SAN ANTONIO, TX
537 PM CDT SUN MAY 20 1990

SCATTERED THUNDERSTORMS...SOME WITH VERY HEAVY RAINFALL...CONTINUED
AT 530 PM BETWEEN LAREDO AND COTULLA.  THE THUNDERSTORMS WERE MOVING
TO THE NORTHEAST AT 20 MPH.

TEMPERATURES REACHED 109 DEGREES IN LAREDO THIS AFTERNOON...WITH 102
DEGREES REPORTED AT COTULLA.  SUCH EXTREME HEAT DEVELOPES THUNDERSTORMS
WITH BASES SEVERAL THOUSAND FEET ABOVE THE GROUND.  A STORM OF THIS TYPE
HAS THE POTENTIAL FOR PRODUCING VERY STRONG AND GUSTY WINDS...THAT AT
TIMES CAN BE DAMAGING.  OFTEN THE RAIN FALLING FROM THESE STORMS IS SEEN
TO EVAPORATE BEFORE IT REACHES THE GROUND.  IS IS A VISUAL SIG.N THAT THE
STORMS COULD PRODUCE DAMAGING WINDS.
Special weather statement, May 20, 6:05 PM CDT, 1 hour 57 minutes before
TXZ035-040-210010-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SAN ANTONIO, TX
605 PM CDT SUN MAY 20 1990

...SEVERE THUNDERSTORM WARNING IN EFFECT FOR WEBB COUNTY UNTIL 715 PM...

AT 600 PM...WEATHER SERVICE RADAR INDICATED AN AREA OF SCATTERED TO
NUMEROUS THUNDERSTORMS BETWEEN LAREDO AND COTULLA.  THE STORMS WERE
MOVING TO THE NORTHEAST AT 10 MPH.

THE ATMOSPHERE IS VERY UNSTABLE OVER WEBB COUNTY THIS AFTERNOON...WHERE
AFTERNOON HIGH TEMPERATURES HAVE REACHED WELL ABOVE 100 DEGREES.  THESE
THUNDERSTORMS HAVE THE POTENTIAL TO DEVELOP VERY RAPIDLY...PRODUCE
BURSTS OF DAMAGING WINDS...AND THEN SUBSIDE ONLY TO BUILD AGAIN IN A
NEW AREA.  THE GREATEST DANGER IN THESE STORMS ARE DAMAGINrG WINDS AND
DEADLY LIGHTNING.  HAIL IS ALSO POSSIBLE IN THE STORMS.

THE BEST PROTECTION FROM A SEVERE THUNDERSTORM IS FOUND INSIDE A WELL-
BUILT BUILDING OR HOME...AWAY FROM DOORS AND WINDOWS.
Special weather statement, May 20, 6:56 PM CDT, 1 hour 6 minutes before
TXZ035-040-210200-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SAN ANTONIO, TX
655 PM CDT SUN MAY 20 1990

...SEVERE THUNDERSTORM WARNING IN EFFECT FOR WEBB COUNTY UNTIL 715 PM...

AT 650 PM...SCATTERED THUNDERSTORMS CONTINUED OVER MOST OF WEBB COUNTY.
THE STORMS WERE MOVING TO THE EAST AT 15 MPH.

MARBLE-SIZED HAIL WAS REPORTED BY THE DEPARTMENT OF PUBLIC SAFETY IN
LAREDO AT 625 PM THIS EVENING.  THE PUBLIC ALSO REPORTED QUARTER-INCH
HAIL IN THE CITY SHORTLY AFTER 630 PM.  NO INFORMATION HAS BEEN
RECEIVED FROM JUST NORTH OF THE CITY OF LAREDO WHERE THE MOST INTENSE
THUNDERSTORMS WERE INDICATED BY RADAR.

THE STORMS HAVE BEGUN TO MOVE EASTWARD WITHIN THE PAST HALF HOUR.  IF
THIS MOVEMENT CONTINUES...THEY WILL LEAVE WEBB COUNTY WITHIN THE NEXT
HALF HOUR...ENDING THE THREAT OF SEVERE WEATHER.
Special weather statement, May 20, 7:59 PM CDT, 3 minutes before
TXZ035-040-210300-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SAN ANTONIO, TX
759 PM CDT SUN MAY 20 1990

SCATTERED THUNDERSTORMS...SOME WITH VERY HEAVY RAINFALL...WERE LOCATED
BETWEEN COTULLA...TILDEN AND SAN DIEGO AT 755 PM THIS EVENING.  THE
STORMS WERE MOVING TO THE NORTHEAST AT 20 MPH.

THESE THUNDERSTORMS WERE ALL THAT WAS LEFT FROM THE ORIGINAL AREA OF
SEVERE THUNDERSTORMS THAT FORMED NEAR LAREDO AT 500 PM THIS EVENING.
HAIL OF UP TO 1.25 INCHES IN DIAMETER WAS REPORTED JUST NORTH OF LAREDO
WITH .75 INCH DIAMETER HAIL JUST TO THE EAST OF THE CITY.

BECAUSE OF THE VERY HOT AFTERNOON TEMPERATURES AND THE VERY UNSTABLE
AIRMASS IN THE AREA WHERE THE STORMS ARE STILL MOVING...THE} POTENTIAL
STILL EXISTS FOR LARGE HAIL...AS WELL AS DAMAGING WINDS AND VERY DEADLY
LIGHTNING.
Special weather statement, May 20, 8:00 PM CDT, 2 minutes before
TXZ041-210300-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SAN ANTONIO, TX
759 PM CDT SUN MAY 20 1990

SCATTERED THUNDERSTORMS...SOME WITH VERY HEAVY RAINFALL...WERE LOCATED
BETWEEN COTULLA...TILDEN AND SAN DIEGO AT 755 PM THIS EVENING.  THE
STORMS WERE MOVING TO THE NORTHEAST AT 20 MPH.

THESE THUNDERSTORMS WERE ALL THAT WAS LEFT FROM THE ORIGINAL AREA OF
SEVERE THUNDERSTORMS THAT FORMED NEAR LAREDO AT 500 PM THIS EVENING.
HAIL OF UP TO 1.25 INCHES IN DIAMETER WAS REPORTED JUST NORTH OF LAREDO
WITH .75 INCH DIAMETER HAIL JUST TO THE EAST OF THE CITY.

BECAUSE OF THE VERY HOT AFTERNOON TEMPERATURES AND THE VERY UNSTABLE
AIRMASS IN THE AREA WHERE THE STORMS ARE STILL MOVING...THE POTENTIAL
STILL EXISTS FOR LARGE HAIL...AS WELL AS DAMAGING WINDS AND VERY DEADLY
LIGHTNING.

The office that day

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

IssuedProductOfficeCountiesLasted
May 20, 8:35 PM CDTSevere Thunderstorm WarningEWXAtascosa55 min
May 20, 9:21 PM CDTSevere Thunderstorm WarningEWXAtascosa54 min
May 20, 10:20 PM CDTSevere Thunderstorm WarningEWXBexar50 min
May 20, 10:29 PM CDTSevere Thunderstorm WarningEWXWilson76 min
May 20, 10:59 PM CDTSevere Thunderstorm WarningEWXGonzales61 min
May 21, 2:06 PM CDTSevere Thunderstorm WarningEWXKerr69 min
May 21, 2:37 PM CDTTornado WarningEWXKerr68 min
May 21, 5:23 PM CDTSevere Thunderstorm WarningEWXTravis67 min
May 21, 6:07 PM CDTSevere Thunderstorm WarningEWXUvalde68 min
May 21, 6:15 PM CDTSevere Thunderstorm WarningEWXWilliamson45 min
May 21, 6:30 PM CDTSevere Thunderstorm WarningEWXTravis30 min
May 21, 6:44 PM CDTSevere Thunderstorm WarningEWXVal Verde61 min

Nearby

Severe Thunderstorm Warnings in Texas, 1990Every severe thunderstorm warning in 1990

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.