Alert archive / Texas / Flash Flood Warnings in 1999
Flash Flood Warning 23, NWS Austin/San Antonio, TX
NWS Austin/San Antonio, TX issued this flash flood warning at May 11, 1999, 6:18 PM CDT 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
- May 11, 1999, 6:18 PM CDT (23:18 UTC)
- Expired
- May 11, 1999, 9:20 PM CDT
- In force
- 3 hr
- Issued by
- NWS Austin/San Antonio, TX
- Area
- Whole counties
County Llano County, TX
The radar
The Ft Hood radar (KGRK), 124 km from the middle of the area, began a volume at 23:17 UTC, the scan nearest the moment this went out.
Open the radar archive at this moment
The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.
The nearest sounding before it
Del Rio, TX (KDRT), launched 12:00Z, 11.3 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.
- Mixed-layer CAPE
- 2571 J/kg
- Mixed-layer CIN
- -131 J/kg
- Mixed-layer LCL
- 553 m above ground
- 0-6 km bulk shear
- 26 kt
- 0-1 km storm-relative helicity
- 126 m²/s²
- 0-3 km storm-relative helicity
- 186 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 3.8
The text
As transmitted, in the capitals the NWS used until 2016.
000 TTAA00 KEWX 112325 COR FFWSAT TXC299-120220- BULLETIN - EAS ACTIVATION REQUESTED FLASH FLOOD WARNING...CORRECTION NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX 618 PM CDT TUE MAY 11 1999 THE NATIONAL WEATHER SERVICE IN AUSTIN/SAN ANTONIO HAS ISSUED A * FLASH FLOOD WARNING FOR... LLANO COUNTY IN TEXAS * UNTIL 920 PM CDT * AT 610 PM... NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A THUNDERSTORM WITH VERY HEAVY RAIN ALONG THE LLANO MASON COUNTY LINE... MOVING NEARLY STATIONARY. * RAINFALL RATES ESTIMATED NEAR 2 INCHES AN HOUR. LOW WATER CROSSING IN THE AREA WILL BECOME FLOODED. MOVE TO HIGHER GROUND IF FLOOD WATERS THREATEN. BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE DANGERS OF FLOODS AND FLASH FLOODS. IF FLASH FLOODING IS OBSERVED... ACT QUICKLY. MOVE UP TO ESCAPE FLOOD WATERS. DO NOT STAY IN AREAS SUBJECT TO FLOODING WHEN WATER BEGINS RISING. IT IS VERY DIFFICULT AT NIGHT TO TELL HOW MUCH WATER IS ON ROADS. "MOTORISTS SHOULD NOT DRIVE THROUGH WATER OF UNKNOWN DEPTH. CFM
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 11, 2:45 PM CDT, 3 hours 33 minutes before
TXZ171>173-183>194-202>209-217>225-228-112300- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX 245 PM CDT TUE MAY 11 1999 ...THREAT OF SEVERE WEATHER LATE THIS AFTERNOON AND TONIGHT... ...FLASH FLOOD WATCH IN EFFECT TONIGHT FOR THE HILL COUNTRY AND MOST OF SOUTH CENTRAL TEXAS... TO THE NORTH AND WEST...CONVECTION HAS BEGUN OVER THE HILL COUNTRY AHEAD OF THE COLD FRONTAL BOUNDARY BETWEEN SAN ANGELO AND JUNCTION. THE PRESENCE OF THE COLD FRONT...A VERY UNSTABLE AIRMASS OVER SOUTH TEXAS AND VERY WARM DAYTIME HIGHS...WILL TRIGGER STRONG TO SEVERE THUNDERSTORMS LATE THIS AFTERNOON AND THIS EVENING OVER THE HILL COUNTRY. THE STORMS WILL BE CAPABLE OF PRODUCING LARGE HAIL AND WIND GUSTS IN EXCESS OF 60 MPH AS THEY MOVE EAST ACROSS THE HILL COUNTRY INTO SOUTH CENTRAL TEXAS. AN UPPER LEVEL DISTURBANCE WILL INTERACT WITH THE COLD FRONT THIS EVENING...INCREASING THE CHANCES OF SEVERE THUNDERSTORM DEVELOPMENT. AS THE EVENING PROGRESSES INTO THE OVERNIGHT HOURS...THE STORMS WILL EVOLVE INTO HEAVY RAIN PRODUCERS. A FLASH FLOOD WATCH REMAINS IN EFFECT TONIGHT ALONG AND EAST OF A LINE FROM MENARD TO ROCKSPRINGS TO HONDO TO KARNES CITY AND CUERO. LAW ENFORCEMENT AGENCIES...EMERGENCY MANAGEMENT OFFICIALS...STORM SPOTTER GROUPS...AND OTHER INTERESTED CONCERNS SHOULD MONITOR THIS SITUATION AND TAKE APPROPRIATE ACTION SHOULD SEVERE WEATHER THREATEN YOUR AREA. STAY TUNED TO NOAA WEATHER RADIO...COMMERCIAL TELEVISION OR RADIO STATIONS...OR YOUR CABLE TELEVISION PROVIDER FOR LATER STATEMENTS CONCERNING THIS POTENTIALLY DANGEROUS SEVERE WEATHER THREAT.
Special weather statement, May 11, 2:45 PM CDT, 3 hours 33 minutes before
TXZ171>173-183>194-202>209-217>225-228-112300- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX 245 PM CDT TUE MAY 11 1999 ...THREAT OF SEVERE WEATHER LATE THIS AFTERNOON AND TONIGHT... ...FLASH FLOOD WATCH IN EFFECT TONIGHT FOR THE HILL COUNTRY AND MOST OF SOUTH CENTRAL TEXAS... TO THE NORTH AND WEST...CONVECTION HAS BEGUN OVER THE HILL COUNTRY AHEAD OF THE COLD FRONTAL BOUNDARY BETWEEN SAN ANGELO AND JUNCTION. THE PRESENCE OF THE COLD FRONT...A VERY UNSTABLE AIRMASS OVER SOUTH TEXAS AND VERY WARM DAYTIME HIGHS...WILL TRIGGER STRONG TO SEVERE THUNDERSTORMS LATE THIS AFTERNOON AND THIS EVENING OVER THE HILL COUNTRY. THE STORMS WILL BE CAPABLE OF PRODUCING LARGE HAIL AND WIND GUSTS IN EXCESS OF 60 MPH AS THEY MOVE EAST ACROSS THE HILL COUNTRY INTO SOUTH CENTRAL TEXAS. AN UPPER LEVEL DISTURBANCE WILL INTERACT WITH THE COLD FRONT THIS EVENING...INCREASING THE CHANCES OF SEVERE THUNDERSTORM DEVELOPMENT. AS THE EVENING PROGRESSES INTO THE OVERNIGHT HOURS...THE STORMS WILL EVOLVE INTO HEAVY RAIN PRODUCERS. A FLASH FLOOD WATCH REMAINS IN EFFECT TONIGHT ALONG AND EAST OF A LINE FROM MENARD TO ROCKSPRINGS TO HONDO TO KARNES CITY AND CUERO. LAW ENFORCEMENT AGENCIES...EMERGENCY MANAGEMENT OFFICIALS...STORM SPOTTER GROUPS...AND OTHER INTERESTED CONCERNS SHOULD MONITOR THIS SITUATION AND TAKE APPROPRIATE ACTION SHOULD SEVERE WEATHER THREATEN YOUR AREA. STAY TUNED TO NOAA WEATHER RADIO...COMMERCIAL TELEVISION OR RADIO STATIONS...OR YOUR CABLE TELEVISION PROVIDER FOR LATER STATEMENTS CONCERNING THIS POTENTIALLY DANGEROUS SEVERE WEATHER THREAT.
Special weather statement, May 11, 6:00 PM CDT, 18 minutes before
TXZ171-172-183>190-121100- HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX 600 PM CDT TUE MAY 11 1999 ...TORNADO WATCH IN EFFECT TIL 10 PM FOR CENTRAL AND SOUTH CENTRAL TEXAS... ...FLASH FLOOD WATCH IN EFFECT TONIGHT FOR THE TEXAS HILL COUNTRY AND MUCH OF SOUTH CENTRAL TEXAS... HAZARDOUS WEATHER IS EXPECTED TONIGHT AND WEDNESDAY. A MOIST AND UNSTABLE AIRMASS REMAINS OVER SOUTH CENTRAL TEXAS AND THE HILL COUNTRY. STRONG TO SEVERE THUNDERSTORMS ARE EXPECTED TO MOVE INTO THE HILL COUNTRY AND SOUTH CENTRAL TEXAS THIS EVENING AND TONIGHT. THE TORNADO WATCH FOR CENTRAL AND SOUTH CENTRAL TEXAS MEANS CONDITIONS ARE FAVORABLE FOR TORNADOES AND SEVERE THUNDERSTORMS. TORNADOES...HAIL TO THREE INCHES IN DIAMETER...STRONG GUSTY WINDS TO 80 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE. THE FLASH FLOOD WATCH FOR THE HILL COUNTRY AND MUCH OF SOUTH CENTRAL TEXAS MEANS THIS AREA WILL RECEIVE AN ADDITIONAL ONE TO THREE INCHES OF RAIN WITH ISOLATED AMOUNTS UP TO FIVE INCHES POSSIBLE. THIS AREA HAS ALREADY RECEIVED HEAVY RAINFALL FROM THE STORMS SUNDAY NIGHT AND MONDAY. THE ADDITIONAL HEAVY RAINFALL ACROSS THE WATCH AREA WILL RESULT IN RAPID RUNOFF AND FLASH FLOODING. RESIDENTS IN THE WATCH AREA SHOULD MONITOR THE LATEST WEATHER DEVELOPMENTS CONCERNING THIS HEAVY RAINFALL EVENT. STAY INFORMED OF THE WEATHER AND RIVER FORECASTS AND BULLETINS...AND BE READY TO TAKE IMMEDIATE ACTION TO SAFEGUARD LIFE AND PROPERTY IF FLASH FLOODING OR VERY HEAVY RAINFALL IS OBSERVED... OR IF A WARNING IS ISSUED. IF YOU ARE IN A VEHICLE...DO NOT ATTEMPT TO DRIVE ACROSS FLOODED ROADWAYS STAY TUNED TO NOAA WEATHER RADIO...COMMERCIAL RADIO OR TELEVISION STATIONS...OR YOUR CABLE TELEVISION PROVIDER FOR LATER STATEMENTS CONCERNING THIS DANGEROUS SEVERE WEATHER AND FLASH FLOOD THREATS. LAW ENFORCEMENT AGENCIES...EMERGENCY MANAGEMENT OFFICIALS...STORM SPOTTER GROUPS...AND OTHER INTERESTED CONCERNS SHOULD MONITOR THIS SITUATION AND TAKE APPROPRIATE ACTION SHOULD SEVERE WEATHER THREATEN YOUR AREA.
The office that day
Everything else NWS Austin/San Antonio, TX issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 11, 5:06 PM CDT | Severe Thunderstorm Warning | EWX | Llano | 54 min |
| May 11, 5:55 PM CDT | Severe Thunderstorm Warning | EWX | Llano | 60 min |
| May 11, 6:03 PM CDT | Tornado Warning | EWX | Llano | 62 min |
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; radar from the NEXRAD Level II archive.