Alert archive / Texas / Flash Flood Warnings in 1987

Flash Flood Warning 27, NWS Austin/San Antonio, TX

June 1, 1987Zavala County, Texas

NWS Austin/San Antonio, TX issued this flash flood warning at Jun 1, 1987, 11:42 PM CDT for Zavala County, Texas. It was in force for 2 hr.

The area

The counties it named.

The facts

Issued
Jun 1, 1987, 11:42 PM CDT (04:42 UTC)
Expired
Jun 2, 1987, 1:45 AM CDT
In force
2 hr
Issued by
NWS Austin/San Antonio, TX
Area
Whole counties

County Zavala 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, 4.7 hours before the alert went out and 119 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 00:00Z on 1987-06-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3771 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 00:00Z on 1987-06-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 27 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
3771 J/kg
Mixed-layer CIN
-6 J/kg
Mixed-layer LCL
849 m above ground
0-6 km bulk shear
20 kt
0-1 km storm-relative helicity
27 m²/s²
0-3 km storm-relative helicity
190 m²/s²
Significant tornado parameter
1.7
Supercell composite
9.2

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KSAT 020442
FFWSAT
TXC507-020645-
 
BULLETIN - EBS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE SAN ANTONIO TX
1142 PM CDT MON JUN 1 1987
 
THE NATIONAL WEATHER SERVICE HAS ISSUED A FLASH FLOOD WARNING
EFFECTIVE UNTIL  145 AM CDT FOR PEOPLE IN THE FOLLOWING COUNTY...
 
IN SOUTH TEXAS
          ...ZAVALA
 
VERY INTENSE THUNDERSTORMS HAVE CONTINUED OVER CENTRAL ZAVALA COUNTY
FOR THE PAST THIRTY MINUTES.  RAINFALL HAS BEEN ESTIMATED AT NEAR 2
INCHES WITH THE SHERIFFS DEPARTMENT REPORTING STREETS ALREADY RUNNING
FULL AND HEAVY RAIN CONTINUING.  FLASH FLOODING IS EXPECTED
ACROSS THE COUNTY AS THE SLOW MOVING STORMS CONTINUE FOR AT LEAST
ANOTHER HOUR.
 
A FLASH FLOOD WARNING MEANS THAT 9FLOODING IS IMMINENT OR HAS BEEN
REPORTED.

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, Jun 1, 7:47 PM CDT, 3 hours 55 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DEL RIO TX
745 PM CDT MON JUN 1 1987

...THUNDERSTORMS ARE MOVING INTO THE DEL RIO-LAKE AMISTAD AREA...

AT 735 PM CDT RADAR INDICATED A BAND OF THUNDERSTORMS FROM 20 TO 50
MILES NORTH AND WEST OF DEL RIO MOVING INTO THE DEL RIO-LAKE AMISTAD
AREA AT AROUND 10 MPH. A PARTICULARLY INTENSE STORM IS ABOUT 40 MILES
SOUTHWEST OF THE CITY OF DEL RIO AT THIS TIME MOVING EAST.

OTHER THUNDERSTORMS AND SHOWERS STRECH BACK UP THE PECOS VALLEY INTO
SOUTHERN NEW MEXICO AND ARE MOVING DOWN IT TO SOUTHEAST DOWN THE
VALLEY OF THE PECOS INTO THE COUNTY.

BOATERS SHOULD CONSIDER IMMEDIATELY SEEKING SAFE HARBOUR AS STRONG
WINDS AND DANGEROUS LIGHTNING ARE LIKELY NEAR THESE STORMS.

THE POSSIBLITY OF HEAVY RAINS WITH THESE STORMS IS HIGH AS THEY
ARE MOVING SLOWLY EVERYONE DRIVING IN THE CITY AREA SHOULD BE
PREPARED FOR THE FLOODING OF LOW WATER CROSSINGS.

YOUR NATIONAL WEATHER SERVICE WILL ISSUE ADDITIONALS STATEMENTS...SO
STAY TUNED TO YOUR LOCAL RADIO...TV OR NOAA WEATHER RADIO.
Special weather statement, Jun 1, 8:12 PM CDT, 3 hours 30 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SAN ANTONIO TX
812 PM CDT MON JUN 1 1987

SCATTERED THUNDERSTORMS WITH FREQUENT LIGHTNING AND VERY HEAVY RAIN HAVE
CONTINUED FROM NORTHEAST WEBB COUNTY NORTHWARD TO NEAR COTULLA FOR THE
PAST HOUR.  THESE STORMS WERE MOVING TO THE NORTH AT NEAR 15 MPH.  THE
MOST INTENSE STORM WAS LOCATED IN NORTHEAST WEBB COUNTY AND WAS POISED
TO MOVE OVER STATE HIGHWAY 44 WITHIN THE NEXT HALF HOUR.  DUE TO THE
HEAVY RAIN AND REDUCED VISIBILITY...TRAVEL MAY BE VERY DIFFICULT IN AND
NEAR THIS STORM.

MOTORISTS SHOULD ALSO BE ALERT TO BRIEF FLOODING OF LOW LYING AND POORLY
DRAINED AREAS AROUND AND NEAR THESE STRONG THUNDERSTORMS FOR THE NEXT
HOUR OR TWO. 1 NO ONE SHOULD ATTEMPT TO CROSS INTO DEEP WATER.

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 1, 10:45 PM CDTSevere Thunderstorm WarningEWXVal Verde70 min
Jun 1, 11:05 PM CDTFlash Flood WarningEWXVal Verde4 hr
Jun 2, 3:50 PM CDTFlash Flood WarningEWXGuadalupe3 hr
Jun 2, 6:32 PM CDTFlash Flood WarningEWXGonzales, Wilson4 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.