Alert archive / Texas / Tornado Warnings in 1999

Tornado Warning 24, NWS Austin/San Antonio, TX

May 17, 1999Val Verde County, Texas

NWS Austin/San Antonio, TX issued this tornado warning at May 17, 1999, 8:59 PM CDT for Val Verde County, Texas. It was in force for 31 min. 2 reports came from inside the area while it was in force.

The area

The outline the Iowa Environmental Mesonet reconstructed for it; the warning itself named whole counties, with what was reported inside it.

The facts

Issued
May 17, 1999, 8:59 PM CDT (01:59 UTC)
Expired
May 17, 1999, 9:30 PM CDT
In force
31 min
Issued by
NWS Austin/San Antonio, TX
Area
Whole counties; the outline is the Mesonet’s reconstruction

County Val Verde County, TX

The radar

The Laughlin AFB radar (KDFX), 98 km from the middle of the area, began a volume at 02:03 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 17, 9:30 PM CDTThunderstorm WindComstock, TXLarge limbs were blown out of trees by high winds.
May 17, 9:30 PM CDTThunderstorm WindComstock, TXLarge limbs were blown out of trees by high winds.

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 00:00Z, 2.0 hours before the alert went out and 53 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 00:00Z on 1999-05-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 4965 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 00:00Z on 1999-05-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -67 square meters per square second.1939Sfc1 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
4965 J/kg
Mixed-layer CIN
-25 J/kg
Mixed-layer LCL
1037 m above ground
0-6 km bulk shear
31 kt
0-1 km storm-relative helicity
-67 m²/s²
0-3 km storm-relative helicity
-71 m²/s²
Significant tornado parameter
-1.7
Supercell composite
-11.7

Open this sounding in Storm Lab

The text

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

999 
WFUS1 KSAT 180202 RRA
TORSAT
TXC465-180230-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
859 PM CDT MON MAY 17 1999

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

* TORNADO WARNING FOR...
  VAL VERDE COUNTY

* UNTIL 930 PM CDT

* AT 859 PM CDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  THUNDERSTORM WITH A POSSIBLE TORNADO 15 MILES NORTH OF             
  COMSTOCK...  MOVING SOUTH SOUTHWEST AT 30 MPH....GENERALLY ALONG   
  HIGHWAY 163.

THE SAFEST PLACE TO BE DURING A TORNADO IS IN A WELL-BUILT BUILDING.
IF NO BASEMENT IS AVAILABLE...GO TO A CENTRAL...SMALL ROOM ON THE
LOWEST FLOOR...SUCH AS A BATHROOM...CLOSET OR HALLWAY. STAY AWAY FROM
OUTSIDE WINDOWS AND DOORS. USE BLANKETS OR PILLOWS TO COVER YOUR
BODY.

LAT...LON 2989 10096 2996 10115 2969 10131 2953 10114

The office that day

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

IssuedProductOfficeCountiesLasted
May 17, 7:17 PM CDTSevere Thunderstorm WarningEWXBurnet58 min
May 17, 7:24 PM CDTTornado WarningEWXVal Verde36 min
May 17, 8:01 PM CDTSevere Thunderstorm WarningEWXWilliamson59 min
May 17, 8:13 PM CDTSevere Thunderstorm WarningEWXBurnet32 min
May 17, 8:29 PM CDTSevere Thunderstorm WarningEWXBlanco, Gillespie61 min
May 17, 8:42 PM CDTSevere Thunderstorm WarningEWXVal Verde63 min
May 17, 9:29 PM CDTTornado WarningEWXKinney, Val Verde31 min
May 17, 9:58 PM CDTTornado WarningEWXVal Verde17 min
May 17, 10:41 PM CDTFlash Flood WarningEWXTravis79 min
May 17, 10:41 PM CDTSevere Thunderstorm WarningEWXTravis79 min
May 17, 10:49 PM CDTFlash Flood WarningEWXGillespie101 min
May 17, 11:06 PM CDTSevere Thunderstorm WarningEWXCaldwell, Gonzales54 min
May 17, 11:26 PM CDTSevere Thunderstorm WarningEWXGuadalupe64 min
May 17, 11:34 PM CDTSevere Thunderstorm WarningEWXDeWitt, Gonzales, Lavaca86 min
May 17, 11:34 PM CDTSevere Thunderstorm WarningEWXKarnes, Wilson86 min
May 17, 11:39 PM CDTSevere Thunderstorm WarningEWXBexar66 min
May 17, 11:51 PM CDTFlash Flood WarningEWXBandera54 min
May 18, 12:30 AM CDTSevere Thunderstorm WarningEWXUvalde60 min
May 18, 12:56 AM CDTSevere Thunderstorm WarningEWXFrio64 min
May 18, 2:16 AM CDTSevere Thunderstorm WarningEWXMaverick, Zavala64 min

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.