Alert archive / Texas / Severe Thunderstorm Warnings in 1999
Severe Thunderstorm Warning 89, NWS Austin/San Antonio, TX
NWS Austin/San Antonio, TX issued this severe thunderstorm warning at May 11, 1999, 8:50 PM CDT for Williamson County, Texas. It was in force for 60 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, 8:50 PM CDT (01:50 UTC)
- Expired
- May 11, 1999, 9:50 PM CDT
- In force
- 60 min
- Issued by
- NWS Austin/San Antonio, TX
- Area
- Whole counties
County Williamson County, TX
The radar
The Ft Hood radar (KGRK), 22 km from the middle of the area, began a volume at 01:50 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
| Time | Report | Where | Remark |
|---|---|---|---|
| May 11, 9:40 PM CDT | Thunderstorm Wind | Taylor, 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.
| Issued | Product | Office | Lasted |
|---|---|---|---|
| May 11, 3:30 PM CDT | Tornado Watch | SPC | 7 hr |
| May 11, 8:30 PM CDT | Tornado Watch | SPC | 4 hr |
The nearest sounding before it
Fort Worth, TX (KFWD), launched 00:00Z, 1.8 hours before the alert went out and 245 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
- 2666 J/kg
- Mixed-layer CIN
- -27 J/kg
- Mixed-layer LCL
- 881 m above ground
- 0-6 km bulk shear
- 35 kt
- 0-1 km storm-relative helicity
- 31 m²/s²
- 0-3 km storm-relative helicity
- 86 m²/s²
- Significant tornado parameter
- 0.7
- Supercell composite
- 5.7
The text
As transmitted, in the capitals the NWS used until 2016.
999 WUUS1 KSAT 120149 RRA SVRSAT TXC491-120250- BULLETIN - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX 850 PM CDT TUE MAY 11 1999 THE NATIONAL WEATHER SERVICE IN AUSTIN/SAN ANTONIO HAS ISSUED A * SEVERE THUNDERSTORM WARNING FOR... WILLIAMSON COUNTY IN TEXAS * UNTIL 950 PM CDT * AT 845 PM...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM NEAR THE INTERSECTION OF U.S. HIGHWAY 183 AND FARM ROAD 970...WEST OF ANDICE... MOVING SOUTHEAST AT 20 MPH. * THE SEVERE THUNDERSTORM WILL FOLLOW THE SAN GABRIEL RIVER TOWARD LEANDER AND GEORGETOWN. GO INSIDE A STURDY BUILDING AND STAY AWAY FROM WINDOWS A TORNADO WATCH IS IN EFFECT. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY DO PRODUCE TORNADOES WITH LITTLE OR NO ADVANCE WARNING. CFM
What forecasters said that day
The local office's own words before this severe thunderstorm 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, 6:00 PM CDT, 2 hours 50 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, 7:03 PM CDT | Tornado Warning | EWX | Llano | 62 min |
| May 11, 7:22 PM CDT | Severe Thunderstorm Warning | EWX | Gillespie | 63 min |
| May 11, 7:28 PM CDT | Tornado Warning | EWX | Gillespie | 62 min |
| May 11, 8:14 PM CDT | Flash Flood Warning | EWX | Gillespie | 3 hr |
| May 11, 8:14 PM CDT | Flash Flood Warning | EWX | Burnet | 3 hr |
| May 11, 8:26 PM CDT | Tornado Warning | EWX | Gillespie | 64 min |
| May 11, 8:29 PM CDT | Tornado Warning | EWX | Burnet | 61 min |
| May 11, 8:34 PM CDT | Severe Thunderstorm Warning | EWX | Kerr | 61 min |
| May 11, 9:16 PM CDT | Flash Flood Warning | EWX | Williamson | 3 hr |
| May 11, 9:35 PM CDT | Severe Thunderstorm Warning | EWX | Kerr | 60 min |
| May 11, 9:39 PM CDT | Severe Thunderstorm Warning | EWX | Real | 2 hr |
| May 11, 9:57 PM CDT | Severe Thunderstorm Warning | EWX | Kinney, Maverick | 63 min |
| May 11, 10:03 PM CDT | Flash Flood Warning | EWX | Kerr | 3 hr |
| May 11, 10:20 PM CDT | Severe Thunderstorm Warning | EWX | Bandera | 70 min |
| May 11, 10:56 PM CDT | Severe Thunderstorm Warning | EWX | Real | 34 min |
| May 11, 11:03 PM CDT | Severe Thunderstorm Warning | EWX | Kinney | 62 min |
| May 11, 11:14 PM CDT | Severe Thunderstorm Warning | EWX | Uvalde | 61 min |
| May 11, 11:26 PM CDT | Severe Thunderstorm Warning | EWX | Val Verde | 79 min |
| May 11, 11:31 PM CDT | Severe Thunderstorm Warning | EWX | Medina | 64 min |
| May 11, 11:56 PM CDT | Flash Flood Warning | EWX | Kinney, Maverick | 4 hr |
| May 12, 12:03 AM CDT | Severe Thunderstorm Warning | EWX | Kinney | 57 min |
| May 12, 12:15 AM CDT | Severe Thunderstorm Warning | EWX | Uvalde | 60 min |
| May 12, 12:31 AM CDT | Severe Thunderstorm Warning | EWX | Medina | 59 min |
| May 12, 12:35 AM CDT | Flash Flood Warning | EWX | Medina, Uvalde | 3 hr |
| May 12, 12:49 AM CDT | Severe Thunderstorm Warning | EWX | Zavala | 91 min |
| May 12, 1:10 AM CDT | Severe Thunderstorm Warning | EWX | Maverick | 65 min |
| May 12, 1:20 AM CDT | Severe Thunderstorm Warning | EWX | Frio | 80 min |
| May 12, 3:59 AM CDT | Severe Thunderstorm Warning | EWX | Karnes | 61 min |
| May 12, 4:51 AM CDT | Flash Flood Warning | EWX | DeWitt, Karnes | 2 hr |
Nearby
Severe Thunderstorm Warnings in Texas, 1999Every severe thunderstorm 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; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.