Alert archive / Texas / Flash Flood Warnings in 1999

Flash Flood Warning 9, NWS Austin/San Antonio, TX

March 18, 1999Llano County, Texas

NWS Austin/San Antonio, TX issued this flash flood warning at Mar 18, 1999, 9:46 AM CST for Llano County, Texas. It was in force for 3 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Mar 18, 1999, 9:46 AM CST (15:46 UTC)
Expired
Mar 18, 1999, 12:40 PM CST
In force
3 hr
Issued by
NWS Austin/San Antonio, TX
Area
Whole counties

County Llano County, TX

The nearest sounding before it

Del Rio, TX (KDRT), launched 12:00Z, 3.8 hours before the alert went out and 255 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 1999-03-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 1999-03-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -130 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
923 m above ground
0-6 km bulk shear
37 kt
0-1 km storm-relative helicity
-130 m²/s²
0-3 km storm-relative helicity
109 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.4

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KSAT 181545
FFWSAT
TXC299-181840-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
946 AM CST THU MAR 18 1999

THE NATIONAL WEATHER SERVICE IN AUSTIN/SAN ANTONIO HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  LLANO COUNTY IN TEXAS

* UNTIL 1240 PM CST

* AT 940 AM CST... NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  A BAND OF HEAVY THUNDERSTORMS EXTENDING ACROSS SOUTHWESTERN
  LLANO COUNTY INTO THE NORTH CENTRAL PORTIONS OF THE COUNTY...
  MOVEMENT WAS NORTHEAST AT 25 MPH.

* HEAVY THUNDERSTORMS WERE MOVING INTO SOUTHWESTERN LLANO COUNTY
  AND MOVING NORTHEAST OVER AREAS THAT HAVE ALREADY RECEIVED 3
  INCHES OF RAIN.  FURTHER HEAVY STORMS ARE DEVELOPING SOUTHWEST OF
  THE COUNTY AND ARE EXPECTED TO PUSH INTO THESE SAME AREAS DURING
  THE NEXT HOUR.

DON'T DRIVE INTO AREAS WHERE WATER COVERS THE ROAD!

FAST RISES DOWN MINOR STREAMS AND CREEKS ACROSS LLANO COUNTY WILL
FLOOD SECONDARY ROADSL...LOW BRIDGES AND CROSSINGS.   MOTORISTS
SHOULD BE AWARE THAT WATER IN THESE CROSSINGS CAN RISE VERY QUICKLY
TO A LEVEL THAT WILL STALL AUTOS AND FLOAT THEM DOWNSTREAM.

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, Mar 18, 5:30 AM CST, 4 hours 16 minutes before
TXZ171>173-183>194-202>209-217>225-228-182300-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
530 AM CST THU MAR 18 1999

THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS TODAY OVER MUCH OF
SOUTH CENTRAL TEXAS AND THE HILL COUNTRY.  A STRONG MOVING UPPER
STORM SYSTEM OVER NEW MEXICO WAS MOVING SLOWLY EASTWARD INTO WEST
TEXAS.  THE STORMS ARE CAPABLE OF PRODUCING STRONG WINDS AND LARGE
HAIL...AS WELL AS HEAVY RAIN.

A LINE OF STRONG THUNDERSTORMS WITH HEAVY RAIN WAS ALREADY MOVING
INTO THE WESTERN HILL COUNTRY PRODUCING LOCALLY HEAVY RAIN OVER REAL
COUNTY.  IN ADDITION...A COLD FRONT HAS PUSHED INTO SOUTHWEST TEXAS
WHICH WILL BE VERY SLOW MOVING TODAY AND COULD HELP FOCUS HEAVY RAINS
TODAY AND INTO THIS EVENING OVER MUCH OF THE AREA.

AVERAGE RAINFALL AMOUNTS WILL RANGE FROM 1/2 TO 1 INCH WITH HIGHER
TOTALS OF 2 TO 4 INCHES POSSIBLE DUE TO THE EXPECTED SLOW MOVEMENT OF
THE COLD FRONT AND TRAINING OF STORMS FROM SOUTH TO NORTH.

THE HAZARDOUS WEATHER OUTLOOK NORMALLY WILL BE UPDATED BY MEANS OF
THE ZONE FORECASTS, SHORT TERM FORECAST, WATCHES, WARNINGS AND
ADVISORIES.  THE HAZARDOUS WEATHER OUTLOOK ITSELF WILL BE UPDATED
ONLY IF UNEXPECTED HAZARDOUS WEATHER DEVELOPS OR IF EXPECTED
HAZARDOUS WEATHER NO LONGER IS FORECAST TO DEVELOP.

FOR INFORMATION ON WEATHER THREATS IN AREAS SURROUNDING SOUTH
CENTRAL TEXAS, PLEASE REFER TO THE HAZARDOUS WEATHER OUTLOOKS FROM
NWS OFFICES IN MIDLAND, SAN ANGELO, FORT WORTH, HOUSTON/GALVESTON
AND CORPUS CHRISTI.
Special weather statement, Mar 18, 5:30 AM CST, 4 hours 16 minutes before
TXZ171>173-183>194-202>209-217>225-228-182300-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
530 AM CST THU MAR 18 1999

THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS TODAY OVER MUCH OF
SOUTH CENTRAL TEXAS AND THE HILL COUNTRY.  A STRONG MOVING UPPER
STORM SYSTEM OVER NEW MEXICO WAS MOVING SLOWLY EASTWARD INTO WEST
TEXAS.  THE STORMS ARE CAPABLE OF PRODUCING STRONG WINDS AND LARGE
HAIL...AS WELL AS HEAVY RAIN.

A LINE OF STRONG THUNDERSTORMS WITH HEAVY RAIN WAS ALREADY MOVING
INTO THE WESTERN HILL COUNTRY PRODUCING LOCALLY HEAVY RAIN OVER REAL
COUNTY.  IN ADDITION...A COLD FRONT HAS PUSHED INTO SOUTHWEST TEXAS
WHICH WILL BE VERY SLOW MOVING TODAY AND COULD HELP FOCUS HEAVY RAINS
TODAY AND INTO THIS EVENING OVER MUCH OF THE AREA.

AVERAGE RAINFALL AMOUNTS WILL RANGE FROM 1/2 TO 1 INCH WITH HIGHER
TOTALS OF 2 TO 4 INCHES POSSIBLE DUE TO THE EXPECTED SLOW MOVEMENT OF
THE COLD FRONT AND TRAINING OF STORMS FROM SOUTH TO NORTH.

THE HAZARDOUS WEATHER OUTLOOK NORMALLY WILL BE UPDATED BY MEANS OF
THE ZONE FORECASTS, SHORT TERM FORECAST, WATCHES, WARNINGS AND
ADVISORIES.  THE HAZARDOUS WEATHER OUTLOOK ITSELF WILL BE UPDATED
ONLY IF UNEXPECTED HAZARDOUS WEATHER DEVELOPS OR IF EXPECTED
HAZARDOUS WEATHER NO LONGER IS FORECAST TO DEVELOP.

FOR INFORMATION ON WEATHER THREATS IN AREAS SURROUNDING SOUTH
CENTRAL TEXAS, PLEASE REFER TO THE HAZARDOUS WEATHER OUTLOOKS FROM
NWS OFFICES IN MIDLAND, SAN ANGELO, FORT WORTH, HOUSTON/GALVESTON
AND CORPUS CHRISTI.

The office that day

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

IssuedProductOfficeCountiesLasted
Mar 17, 9:39 PM CSTSevere Thunderstorm WarningEWXVal Verde61 min
Mar 17, 10:46 PM CSTSevere Thunderstorm WarningEWXVal Verde59 min
Mar 17, 11:08 PM CSTTornado WarningEWXVal Verde32 min
Mar 18, 12:49 AM CSTSevere Thunderstorm WarningEWXVal Verde76 min
Mar 18, 2:18 AM CSTSevere Thunderstorm WarningEWXEdwards72 min
Mar 18, 3:25 AM CSTSevere Thunderstorm WarningEWXEdwards60 min
Mar 18, 5:24 AM CSTFlash Flood WarningEWXReal3 hr
Mar 18, 8:47 AM CSTFlash Flood WarningEWXGillespie3 hr
Mar 18, 9:31 AM CSTFlash Flood WarningEWXKerr3 hr
Mar 18, 12:10 PM CSTFlash Flood WarningEWXGillespie110 min
Mar 18, 12:41 PM CSTFlash Flood WarningEWXLlano114 min
Mar 18, 2:49 PM CSTFlash Flood WarningEWXLlano2 hr

Nearby

Flash Flood Warnings in Texas, 1999Every flash flood warning in 1999

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.