Alert archive / Texas / Tornado Warnings in 1999

Tornado Warning 18, NWS Austin/San Antonio, TX

May 11, 1999Llano County, Texas

NWS Austin/San Antonio, TX issued this tornado warning at May 11, 1999, 6:03 PM CDT for Llano County, Texas. It was in force for 62 min. 1 report came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued
May 11, 1999, 6:03 PM CDT (23:03 UTC)
Expired
May 11, 1999, 7:05 PM CDT
In force
62 min
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 23:06 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.

What was reported inside it

TimeReportWhereRemark
May 11, 6:35 PM CDTHail 1.5Castell, TX

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
May 11, 3:30 PM CDTTornado WatchSPC7 hr

The nearest sounding before it

Del Rio, TX (KDRT), launched 12:00Z, 11.1 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 1999-05-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2571 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 1999-05-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 126 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
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

Open this sounding in Storm Lab

The text

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

999 
WFUS1 KSAT 112302
TORSAT
TXC299-120005-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
603 PM CDT TUE MAY 11 1999

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

* TORNADO WARNING FOR...
  LLANO COUNTY IN TEXAS

* UNTIL 705 PM CDT

* AT 601 PM CDT... WAS INDICATED BY NATIONAL WEATHER SERVICE RADAR
  A DEVELOPING TORNADO 23 MILES WEST OF LLANO OR 5 MILES WEST OF
  CASTELL... MOVING NORTHEAST AT 25 MPH.

* SOME CITIES AND LOCATIONS IN THE PATH OF THIS STORM ARE...
  CASTELL AT 610 PM CDT

ABANDON MOBILE HOMES GET BELOW GROUND AS A LAST RESORT
LIE FLAT IN A DITCH AND COVER YOUR HEAD.

CFM

What forecasters said that day

The local office's own words before this tornado 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 18 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 18 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, 3 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.

IssuedProductOfficeCountiesLasted
May 11, 5:06 PM CDTSevere Thunderstorm WarningEWXLlano54 min
May 11, 5:55 PM CDTSevere Thunderstorm WarningEWXLlano60 min
May 11, 6:18 PM CDTFlash Flood WarningEWXLlano3 hr

Nearby

Tornado Warnings in Texas, 1999Every tornado warning in 1999Tornadoes 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; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.