Alert archive / Texas / Flash Flood Warnings in 1987

Flash Flood Warning 5, NWS Austin/San Antonio, TX

May 11, 1987Webb County, Texas

NWS Austin/San Antonio, TX issued this flash flood warning at May 11, 1987, 10:28 AM CDT for Webb County, Texas. It was in force for 2 hr.

The area

The counties it named.

The facts

Issued
May 11, 1987, 10:28 AM CDT (15:28 UTC)
Expired
May 11, 1987, 12:30 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, 3.5 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 1987-05-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 16 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 1987-05-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -17 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
16 J/kg
Mixed-layer CIN
-237 J/kg
Mixed-layer LCL
1244 m above ground
0-6 km bulk shear
6 kt
0-1 km storm-relative helicity
-17 m²/s²
0-3 km storm-relative helicity
40 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 111528
FFWSAT
TXC479-111730-
 
BULLETIN - EBS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE SAN ANTONIO TX
1028 AM CDT MON MAY 11 1987
 
THE NATIONAL WEATHER SERVICE HAS ISSUED A FLASH FLOOD WARNING
EFFECTIVE UNTIL 1230 PM CDT FOR PEOPLE IN THE FOLLOWING COUNTY...
 
IN SOUTH TEXAS
          ...WEBB
 
AN AREA OF THUNDERSTORMS IS LOCATED IN SOUTHERN WEBB COUNTY WITH THE
HEAVIEST THUNDERSTORMS LOCATED NEAR LAREDO TEXAS.  THESE
THUNDERSTORMS ARE MOVING SLOWLY AND ARE CONSEQUENTLY CAUSING HEAVY
RAIN AND FLOODING CONDITIONS.  PEOPLE IN LAREDO SHOULD BE ALERT FOR
HEAVY RAINS AND FLOODING CONDITIONS.  IF YOU LIVE IN OR NEAR AN AREA
PRONED TO FLOODING YOU SHOULD TAKE TO HIGH GROUND IMMEDIATELY.
 
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 ST\REAMS OR DRAINAGE AREAS.

The office that day

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

IssuedProductOfficeCountiesLasted
May 10, 8:33 PM CDTFlash Flood WarningEWXReal117 min
May 11, 12:45 PM CDTFlash Flood WarningEWXMaverick2 hr

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.