Alert archive / Texas / Severe Thunderstorm Warnings in 1999
Severe Thunderstorm Warning 56, NWS Austin/San Antonio, TX
NWS Austin/San Antonio, TX issued this severe thunderstorm warning at Apr 24, 1999, 11:51 AM CDT for Val Verde County, Texas. It was in force for 49 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
- Apr 24, 1999, 11:51 AM CDT (16:51 UTC)
- Expired
- Apr 24, 1999, 12:40 PM CDT
- In force
- 49 min
- Issued by
- NWS Austin/San Antonio, TX
- Area
- Whole counties
County Val Verde County, TX
The radar
The Laughlin AFB radar (KDFX), 109 km from the middle of the area, began a volume at 16:53 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 |
|---|---|---|---|
| Apr 24, 11:55 AM CDT | Hail 1.5 | Del Rio, 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 nearest sounding before it
Del Rio, TX (KDRT), launched 12:00Z, 4.9 hours before the alert went out and 66 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
- 2922 J/kg
- Mixed-layer CIN
- -23 J/kg
- Mixed-layer LCL
- 522 m above ground
- 0-6 km bulk shear
- 41 kt
- 0-1 km storm-relative helicity
- 126 m²/s²
- 0-3 km storm-relative helicity
- 169 m²/s²
- Significant tornado parameter
- 1.6
- Supercell composite
- 8.2
The text
The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.
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, Apr 24, 6:10 AM CDT, 5 hours 41 minutes before
TXZ171>173-183>194-202>209-217>225-228-250000- HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX 610 AM CDT SAT APR 24 1999 SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP THIS AFTERNOON AND TONIGHT AS A COLD FRONT SAGS SOUTHWARD OVER THE HILL COUNTRY AND CONVERGES WITH MOIST...UNSTABLE AIR TO THE EAST AND SOUTH. WITH A TROPICAL PLUME OF MOISTURE ALOFT...SOME OF THE STORMS DEVELOPING ALONG AND JUST NORTH OF THE FRONT OVER PORTIONS OF THE HILL COUNTRY COULD BECOME HEAVY WITH FLOODING OF LOW LYING OR FLOOD PRONE AREAS. PERSONS TRAVELING ACROSS THE HILL COUNTRY THIS AFTERNOON INTO THIS EVENING SHOULD BE ALERT TO THE POSSIBILITY OF LOCALIZED FLOODING AND AVOID LOW WATER CROSSINGS IN HEAVY RAINFALL. RAINFALL AMOUNTS COULD AVERAGE 1/2 INCH ACROSS NORTHERN AND CENTRAL PORTIONS OF THE HILL COUNTRY TODAY AND TONIGHT WITH THE REMAINDER OF SOUTH CENTRAL TEXAS RECEIVING AMOUNTS GENERALLY A QUARTER OF AN INCH OR LESS. LOCALIZED AMOUNTS GREATER THAN 1 AND 1/2 INCHES ARE POSSIBLE IN THE HILL COUNTRY IN SOME OF THE HEAVIER THUNDERSTORMS. 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, Apr 24, 6:10 AM CDT, 5 hours 41 minutes before
TXZ171>173-183>194-202>209-217>225-228-250000- HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX 610 AM CDT SAT APR 24 1999 SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP THIS AFTERNOON AND TONIGHT AS A COLD FRONT SAGS SOUTHWARD OVER THE HILL COUNTRY AND CONVERGES WITH MOIST...UNSTABLE AIR TO THE EAST AND SOUTH. WITH A TROPICAL PLUME OF MOISTURE ALOFT...SOME OF THE STORMS DEVELOPING ALONG AND JUST NORTH OF THE FRONT OVER PORTIONS OF THE HILL COUNTRY COULD BECOME HEAVY WITH FLOODING OF LOW LYING OR FLOOD PRONE AREAS. PERSONS TRAVELING ACROSS THE HILL COUNTRY THIS AFTERNOON INTO THIS EVENING SHOULD BE ALERT TO THE POSSIBILITY OF LOCALIZED FLOODING AND AVOID LOW WATER CROSSINGS IN HEAVY RAINFALL. RAINFALL AMOUNTS COULD AVERAGE 1/2 INCH ACROSS NORTHERN AND CENTRAL PORTIONS OF THE HILL COUNTRY TODAY AND TONIGHT WITH THE REMAINDER OF SOUTH CENTRAL TEXAS RECEIVING AMOUNTS GENERALLY A QUARTER OF AN INCH OR LESS. LOCALIZED AMOUNTS GREATER THAN 1 AND 1/2 INCHES ARE POSSIBLE IN THE HILL COUNTRY IN SOME OF THE HEAVIER THUNDERSTORMS. 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.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 24, 12:02 PM CDT | Flash Flood Warning | EWX | Val Verde | 118 min |
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.