Alert archive / Texas / Flash Flood Warnings in 1987

Flash Flood Warning 3, NWS Austin/San Antonio, TX

May 5, 1987Webb County, Texas

NWS Austin/San Antonio, TX issued this flash flood warning at May 5, 1987, 6:54 PM CDT for Webb County, Texas. It was in force for 2 hr.

The area

The counties it named.

The facts

Issued
May 5, 1987, 6:54 PM CDT (23:54 UTC)
Expired
May 5, 1987, 9:00 PM CDT
In force
2 hr
Issued by
NWS Austin/San Antonio, TX
Area
Whole counties

County Webb 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 12:00Z, 11.9 hours before the alert went out and 232 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 1987-05-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1028 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 1987-05-05The 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
1028 J/kg
Mixed-layer CIN
-27 J/kg
Mixed-layer LCL
797 m above ground
0-6 km bulk shear
9 kt
0-1 km storm-relative helicity
-25 m²/s²
0-3 km storm-relative helicity
8 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.

000 
TTAA00 KSAT 052354
FFWSAT
TXC479-060200-
 
BULLETIN - EBS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE SAN ANTONIO TX
654 PM CDT TUE MAY 5 1987
 
THE NATIONAL WEATHER SERVICE HAS ISSUED A FLASH FLOOD WARNING
EFFECTIVE UNTIL  900 PM CDT FOR PEOPLE IN THE FOLLOWING COUNTY...
 
IN SOUTH TEXAS
          ...WEBB
 
THE DEPARTMENT OF PUBLIC SAFETY IN LAREDO REPORTS THAT HEAVY RAIN IN
THE PAST HOUR HAS PRODUCED FLASH FLOODING IN THE CITY OF LAREDO.
MOTORISTS ARE REPORTED TO BE STRANDED WITH WATER CONTINUING TO RISE
IN MANY SECTIONS OF THE CITY.
 
 
A FLASH FLOOD WARNING MEANS THAT FLOODING IS IMMINENT OR HAS BEEN
REPORTED.
 
REMEMBER...DEATHS DURING FLASH FLOODING ARE FREQUENTLY RELATED TO
MOTORISTS DRIVING INTO FLOODED LOW WATER CROSSINGS OR FROM CHILDREN
PLAYING NEAR FLOODED STREAMS OR DRAINAGE AREAS.

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.

In the hours before

Special weather statement, May 5, 4:27 PM CDT, 2 hours 27 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SAN ANTONIO TX
425 PM CDT TUE MAY 5 1987

THUNDERSTORMS THAT FORMED IN THE EARLY AFTERNOON OVER SOUTH CENTRAL
TEXAS HAVE CONTINUED TO INCREASE IN BOTH INTENSITY AND COVERAGE.

AT 420 PM CDT THIS AFTERNOON...WEATHER SERVICE RADAR INDICATED AN AREA
OF SCATTERED THUNDERSTORMS COVERING MOST OF SOUTH CENTRAL TEXAS.  THE
MOST INTENSE STORMS WERE LOCATED FROM GONZALES ACROSS FLORESVILLE AND
JOURDANTON TO NEAR CRYSTAL CITY.  THE STORMS WERE MOVING TO THE NORTH AT
BETWEEN 5 AND 10 MILES AN HOUR.

BECAUSE OF THEIR SLOW MOVEMENT...THE MORE INTENSE STORMS ARE LIKELY TO
PRODUCE RAIN ACCUMULATIONS REACHING 1 TO 2 INCHES IN SOME LOCATIONS.
WATER MAY BEGIN TO COLLECT IN LOW LYING AND POORLY DRAINED AREAS.
MOTORISTS NEED TO BE ALERT WHEN DRIVING NEAR AREAS OF HEAVY RAINFALL AND
BE CAREFUL NOT TO DRIVE INTO DEEP WATER.
Special weather statement, May 5, 5:10 PM CDT, 1 hour 44 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SAN ANTONIO TX
510 PM CDT TUE MAY 5 1987

AT 505 PM CDT SCATTERED THUNDERSTORMS CONTINUED ACROSS A LARGE PORTION
OF SOUTH CENTRAL TEXAS.  THE MOST INTENSE STORMS WERE LOCATED FROM
GONZALES TO FLORESVILLE AND JOURDANTON TO NEAR CRYSTAL CITY...AS WELL AS
FROM COTULLA TO JUST NORTH OF LAREDO.  HEAVY RAIN WAS ALSO INDICATED IN
EXTREME SOUTHERN BEXAR COUNTY.  THE STORMS WERE MOVING TO THE NORTHEAST
AT BETWEEN 5 AND 10 MILES AN HOUR.

PEA SIZED HAIL WAS REPORTED AT BEBE...10 MILES SOUTHWEST OF GONZALES...
AT 415 PM THIS AFTERNOON.  PEA TO MARBLE SIZED HAIL WAS INDICATED IN
EXTREME SOUTHERN BEXAR COUNTY NEAR 500 PM THIS AFTERNOON.

ADDITIONAUL SMALL HAIL...ALONG WITH VERY HEAVY DOWNPOURS AND BRIEF GUSTY
WINDS ARE LIKELY WITH THESE SLOW MOVING THUNDERSTORMS.  WATER MAY BEGIN
TO COLLECT IN LOW LYING AND POORLY DRAINED AREAS AND MOTORISTS MUST
AVOID DRIVING INTO DEEP WATER.
Special weather statement, May 5, 6:04 PM CDT, 50 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SAN ANTONIO TX
605 PM CDT TUE MAY 5 1987

SCATTERED THUNDERSTORMS WERE INDICATED BY WEATHER SERVICE RADAR AT 600
PM CDT CONTINUING OVER MUCH OF SOUTH CENTRAL TEXAS.  THE MOST INTENSE
STORMS WERE LOCATED NORTH OF LAREDO IN WEBB COUNTY AND FROM NEAR SEGUIN
INTO SOUTHERN BEXAR COUNTY JUST SOUTH OF SAN ANTONIO.  THE ACTIVITY WAS
MOVING TO THE NORTHEAST AT 5 TO 10 MILES AN HOUR.

NO SEVERE WEATHER HAS BEEN INDICATED IN THESE STORMS...HOWEVER SMALL
HAIL AND VERY HEAVY RAINFALL HAVE BEEN REPORTED.

BRIEF GUSTY WINDS AND VERY INTENSE LIGHTNING DISCHARGES ARE LIKELY WITH
THESE SLOW MOVING THUNDERSTORMS.  EVERYONE SHOULD REMEMBER THAT
LIGHTNING IS ONE OF THE MORE FREQUENT CAUSES OF WEATHER RELATED DEATHS
IN SOUTH TEXAS.  FOR SAFETY...MOVE INDOORS...STAY AWAYS FROM DOORS AND
WINDOWS AND DO NOT USE THE TELEPHONE.
Special weather statement, May 5, 6:38 PM CDT, 16 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE AUSTIN TX
635 PM CDT MON MAY 5 1987

RADAR INDICATED VERY STRONG THUNDERSTORMS NEAR LULING...NORTH OF
LEXINGTON AND EAST OF ROCKDALE. THESE THUNDERSTORMS WILL LIKELY
PRODUCE SMALL HAIL...STRONG GUSTY WINDS AND LOCAL HEAVY RAIN.

THESE THUNDERSTORMS ARE MOVING VERY SLOW NORTHWARD.

CONSIDERABLE SMALL...ABOUT 1/4 INCH...HAIL WAS REPORTED IN PART OF
LULING.

Nearby

Flash Flood Warnings in Texas, 1987Every flash flood 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.