Alert archive / Texas / Severe Thunderstorm Warnings in 1999

Severe Thunderstorm Warning 120, NWS Austin/San Antonio, TX

May 18, 1999Maverick County, Zavala County, Texas

NWS Austin/San Antonio, TX issued this severe thunderstorm warning at May 18, 1999, 2:16 AM CDT for Maverick County, Zavala County, Texas. It was in force for 64 min. 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 18, 1999, 2:16 AM CDT (07:16 UTC)
Expired
May 18, 1999, 3:20 AM CDT
In force
64 min
Issued by
NWS Austin/San Antonio, TX
Area
Whole counties

Counties Maverick County, TX, Zavala County, TX

The radar

The Laughlin AFB radar (KDFX), 57 km from the middle of the area, began a volume at 07:19 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 watch it was issued in

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

IssuedProductOfficeLasted
May 18, 1:00 AM CDTSevere Thunderstorm WatchSPC6 hr

The nearest sounding before it

Del Rio, TX (KDRT), launched 00:00Z, 7.3 hours before the alert went out and 100 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

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

Local storm report, May 17, 9:56 PM CDT, 4 hours 20 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
951 PM CST MON MAY 17 1999

TIME(CST)  .....CITY LOCATION..... STATE  ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0930 PM    COMSTOCK                  TX   .5 INCH HAIL
05/17/99   VAL VERDE                      HWY 163 13 MI. N. OF
                                          COMSTOCK REPORTED BY
                                          COUNTY SD

0930 PM    BURNET                    TX   .5 INCH HAIL
05/17/99   BURNET                         MARBLE SIZE HAIL REPORTED
                                          BY HAMS IN BURNET COUNTY
Local storm report, May 17, 10:51 PM CDT, 3 hours 25 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
951 PM CST MON MAY 17 1999

TIME(CST)  .....CITY LOCATION..... STATE  ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0930 PM    COMSTOCK                  TX   .5 INCH HAIL
05/17/99   VAL VERDE                      HWY 163 13 MI. N. OF
                                          COMSTOCK REPORTED BY
                                          COUNTY SD

0930 PM    BURNET                    TX   .5 INCH HAIL
05/17/99   BURNET                         MARBLE SIZE HAIL REPORTED
                                          BY HAMS IN BURNET COUNTY

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, 8:59 PM CDTTornado WarningEWXVal Verde31 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

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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.