Alert archive / Texas / Severe Thunderstorm Warnings in 1987
Severe Thunderstorm Warning 103, NWS Austin/San Antonio, TX
NWS Austin/San Antonio, TX issued this severe thunderstorm warning at May 20, 1987, 10:20 PM CDT for Val Verde County, Texas. It was in force for 60 min.
The area
The counties it named.
The facts
- Issued
- May 20, 1987, 10:20 PM CDT (03:20 UTC)
- Expired
- May 20, 1987, 11:20 PM CDT
- In force
- 60 min
- Issued by
- NWS Austin/San Antonio, TX
- Area
- Whole counties
County Val Verde 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
Del Rio, TX (KDRT), launched 00:00Z, 3.3 hours before the alert went out and 66 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.
- Mixed-layer CAPE
- 2341 J/kg
- Mixed-layer CIN
- -40 J/kg
- Mixed-layer LCL
- 1554 m above ground
- 0-6 km bulk shear
- 37 kt
- 0-1 km storm-relative helicity
- 81 m²/s²
- 0-3 km storm-relative helicity
- 137 m²/s²
- Significant tornado parameter
- 0.4
- Supercell composite
- 5.6
The text
As transmitted, in the capitals the NWS used until 2016.
000 TTAA00 KDRT 210328 COR SVRDRT TXC465-210320- BULLETIN - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE DEL RIO TX 1028 PM CDT WED MAY 20 1987 THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 1120 PM CDT FOR PEOPLE IN THE FOLLOWING COUNTY IN SOUTHCENTRAL TEXAS...VAL VERDE THE TORNADO WARNING ISSUED EARLIER FOR PERSONS IN VAL VERDE COUNTY TX HAS EXPIRED. A LARGE SEVERE THUNDERSTORM WAS LOCATED EAST OF DEL RIO NEAR LAUGHLIN AFB OUT TO THE KINNY VAL VERDE COUNTY LINE. THIS SEVERE THUNDERSTORM WAS MOVING EAST AT 20 MPH. THIS CONTINUES TO BE A VERY DANGEROUS STORM. AS THIS THUNDERSTORM MOVED ACROSS THE LAKE AMISTAD AND THE CITY OF DEL RIO IT PRODUCED A A POSSIBLE TORNADO...WINDS UP TO 73 MPH...MARBLE SIZE HAIL AND VERY HEAVY RAIN.. PERSONS IN THE PATH OF THIS DANGEROUS THUNDERSTORM SHOULD MOVE INSIDE A STRONG BUILDING. STAY INSIDE AWAY FROM WINDOWS UNTIL THE STORM HAS PASSED. REMEMBER SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 60 MPH..DESTRUCTIVE HAIL..DEADLY LIGHTNING AND VERY HEAVY RAIN. FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF YOUR HOME OR BUSINESS. HEAVY RAINS FLOOD ROADS QUICK>LY SO DONT DRIVE INTO AREAS WHERE WATER COVERS THE ROAD.
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, 7:40 PM CDT, 2 hours 40 minutes before
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE AUSTIN TX 740 PM CDT WED MAY 20 1987 SEVERE THUNDERSTORM ACTIVITY CONTINUES IN AND AROUND THE CITY OF SAN ANTONIO SPREADING NORTH AND EASTWARD. THESE SEVERE THUNDERSTORMS ARE ONLY 50 TO 60 MILES SOUTHWEST OF AUSTIN ...BUT THEY ARE EXPECTED TO DIMINISHING IN INTENSITY AFTER SUNSET AS THEY APPROACH CALDWELL AND HAYS COUNTIES. RESIDENTS IN HAYS AND CALDWELL COUNTIES SHOULD STAY ALERT TO THE MOVMENT OF THESE STORMS FOR THE NEXT ONE TO TWO HOURS.
Special weather statement, May 20, 8:09 PM CDT, 2 hours 11 minutes before
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE AUSTIN TX 805 PM CDT WED MAY 20 1987 A SEVERE THUNDERSTORM WAS LOCATED OVER THE CENTRAL PORTIONS OF COMAL COUNTY MOVING TOWARDS THE NORTH. THIS SEVERE THUNDERSTORM IS LOCATED ABOUT 45 MILES MILES SOUTHWEST OF AUSTIN MOVING TOWARDS HAYS AND BLANCO COUNTIES. RESIDENTS IN HAYS AND BLANCO COUNTIES SHOULD STAY ALERT TO THE MOVMENT OF THIS SEVERE STORM FOR THE NEXT HOUR...FOR IF THE STORM CONTINUES/ AT ITS PRESENT INTENSITY A SEVERE THUNDESTORM WARNING MAYBE ISSUED FOR EITHER OR BOTH HAYS AND BLANCO COUNTIES.
Special weather statement, May 20, 8:23 PM CDT, 1 hour 57 minutes before
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
Local storm report, May 20, 8:28 PM CDT, 1 hour 52 minutes before
STORM REPORT
NATIONAL WEATHER SERVICE SAN ANTONIO TX
825 PM CDT WED MAY 20 1987
TIME EVENT
720 PM NUMEROUS REPORTS OF PEA AND MARBLE SIZE HAIL NORTHEAST
SAN ANTONIO...BEXAR COUNTY
725 PM ESTIMATED WIND GUST TO 50 MPH JUDSON AND NACOGDOCHES ROADS
NORTHEAST SAN ANTONIO...BEXAR COUNTY
730 PM POSSIBLE TORNADO INDICATED NE OF SAN ANTONIO BY RANDOLPH
AFB RADAR...BEXAR COUNTY
802 PM < HALF INCH HAIL 13MILES WEST OF NEW BRAUNFELS..COMAL COUNTY
803 PM LARGE HAIL AND HIGH WINDS FM 3159 SOUTH OF CANYON LAKE
...COMAL COUNTY
810 PM PEA SIZE HAIL AT CANYON LAKE...COMAL COUNTYSpecial weather statement, May 20, 10:08 PM CDT, 12 minutes before
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE AUSTIN TX 1005 PM CDT WED MAY 20 1987 THE SEVERE THUNDERSTORM WARNING ISSUED AT 927 PM FOR PERSONS IN TRAVIS COUNTY IS NO LONGER IN EFFECT. THIS THUNDERSTORM IS DECREASING IN INTENSITY AND MOVING INTO THE SOUTHWEST PORTIONS OF WILLIAMSON COUNTY WITH A MOVEMENT TOWARDS THE NORTH NORTHEAST. AS THIS THUNDERSTORMS MOVES OVER THE CENTRAL PORTIONS OF WILLIAMSON COUNTY IT MAY PRODUCE SMALL HAIL...BR0IEF HEAVY RAINFALL AND GUSTY WINDS. NO DAMAGE REPORTS HAVE BEEN RECEIVED AT THE AUSTIN WEATHER SEVERE OFFICE FROM BLANCO...HAYS OR WESTERN TRAVIS COUNTY TONIGHT.
Local storm report, May 20, 10:11 PM CDT, 9 minutes before
STORM REPORT
NATIONAL WEATHER SERVICE SAN ANTONIO TX
1008 PM CDT WED MAY 20 1987
TIME EVENT
842 PM MARBLE TO GOLF BALL SIZE HAIL...TREES BENDING HEAVILY...
COMAL COUNTY
10011 PM FROM DEL RIO TEXAS...WIND GUST TO 73 MPH...1 INCH RAIN...
MARBLE SIZE HAIL...MOVING INTO KINNEY COUNTYThe office that day
Everything else NWS Austin/San Antonio, TX issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 20, 7:11 PM CDT | Severe Thunderstorm Warning | EWX | Wilson | 64 min |
| May 20, 7:38 PM CDT | Severe Thunderstorm Warning | EWX | Atascosa, Frio | 67 min |
| May 20, 7:42 PM CDT | Severe Thunderstorm Warning | EWX | Comal | 63 min |
| May 20, 8:34 PM CDT | Severe Thunderstorm Warning | EWX | Blanco, Hays | 56 min |
| May 20, 8:50 PM CDT | Severe Thunderstorm Warning | EWX | Val Verde | 56 min |
| May 20, 8:56 PM CDT | Severe Thunderstorm Warning | EWX | Maverick | 64 min |
| May 20, 9:00 PM CDT | Tornado Warning | EWX | Uvalde, Zavala | 60 min |
| May 20, 9:03 PM CDT | Severe Thunderstorm Warning | EWX | Atascosa, Frio | 57 min |
| May 20, 9:27 PM CDT | Severe Thunderstorm Warning | EWX | Travis | 63 min |
| May 20, 9:27 PM CDT | Tornado Warning | EWX | Val Verde | 58 min |
| May 20, 9:47 PM CDT | Severe Thunderstorm Warning | EWX | Kinney | 58 min |
| May 20, 10:37 PM CDT | Severe Thunderstorm Warning | EWX | Edwards | 68 min |
| May 20, 10:42 PM CDT | Severe Thunderstorm Warning | EWX | Medina, Uvalde, Zavala | 63 min |
| May 20, 11:47 PM CDT | Severe Thunderstorm Warning | EWX | Medina, Uvalde, Zavala | 58 min |
| May 21, 1:00 AM CDT | Severe Thunderstorm Warning | EWX | Uvalde | 60 min |
| May 21, 6:17 AM CDT | Flash Flood Warning | EWX | Bexar | 3 hr |
| May 21, 6:23 PM CDT | Severe Thunderstorm Warning | EWX | Llano | 67 min |
Nearby
Severe Thunderstorm Warnings in Texas, 1987Every severe thunderstorm warning in 1987
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.