Alert archive / Texas / Tornado Watches in 1999

Tornado Watch 251

May 11, 199943 counties in Texas

The Storm Prediction Center issued this tornado watch at May 11, 1999, 8:30 PM CDT for 43 counties in Texas. It was in force for 4 hr.

The area

The outline as issued.

The facts

Issued
May 11, 1999, 8:30 PM CDT (01:30 UTC)
Expired
May 12, 1999, 12:00 AM CDT
In force
4 hr
Issued by
the Storm Prediction Center
All 43 counties

Anderson County, TX, Atascosa County, TX, Bandera County, TX, Bastrop County, TX, Bell County, TX, Bexar County, TX, Blanco County, TX, Brazos County, TX, Burleson County, TX, Burnet County, TX, Caldwell County, TX, Comal County, TX, Dimmit County, TX, Falls County, TX, Fayette County, TX, Freestone County, TX, Frio County, TX, Gillespie County, TX, Gonzales County, TX, Grimes County, TX, Guadalupe County, TX, Hays County, TX, Houston County, TX, Kendall County, TX, Kerr County, TX, Kinney County, TX, Lee County, TX, Leon County, TX, Limestone County, TX, Madison County, TX, Maverick County, TX, Medina County, TX, Milam County, TX, Real County, TX, Robertson County, TX, Travis County, TX, Trinity County, TX, Uvalde County, TX, Walker County, TX, Washington County, TX, Williamson County, TX, Wilson County, TX, Zavala County, TX

The radar

The Austin/San Antonio radar (KEWX), 58 km from the middle of the area, began a volume at 01:31 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.

Warnings issued inside it

24 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
May 11, 8:34 PM CDTSevere Thunderstorm WarningEWXKerr61 min
May 11, 8:38 PM CDTSevere Thunderstorm WarningFWDFreestone67 min
May 11, 8:50 PM CDTSevere Thunderstorm WarningEWXWilliamson60 min
May 11, 9:15 PM CDTSevere Thunderstorm WarningFWDAnderson, Henderson, Navarro60 min
May 11, 9:16 PM CDTFlash Flood WarningEWXWilliamson3 hr
May 11, 9:31 PM CDTSevere Thunderstorm WarningFWDLeon59 min
May 11, 9:35 PM CDTSevere Thunderstorm WarningEWXKerr60 min
May 11, 9:39 PM CDTSevere Thunderstorm WarningEWXReal2 hr
May 11, 9:41 PM CDTSevere Thunderstorm WarningFWDMilam64 min
May 11, 9:57 PM CDTSevere Thunderstorm WarningEWXKinney, Maverick63 min
May 11, 10:03 PM CDTFlash Flood WarningEWXKerr3 hr
May 11, 10:20 PM CDTSevere Thunderstorm WarningEWXBandera70 min
May 11, 10:23 PM CDTSevere Thunderstorm WarningHGXBurleson67 min
May 11, 10:32 PM CDTSevere Thunderstorm WarningFWDAnderson58 min
May 11, 10:36 PM CDTSevere Thunderstorm WarningFWDLeon54 min
May 11, 10:50 PM CDTSevere Thunderstorm WarningHGXBrazos40 min
May 11, 10:56 PM CDTSevere Thunderstorm WarningEWXReal34 min
May 11, 11:03 PM CDTSevere Thunderstorm WarningEWXKinney62 min
May 11, 11:14 PM CDTSevere Thunderstorm WarningEWXUvalde61 min
May 11, 11:25 PM CDTSevere Thunderstorm WarningHGXBrazos, Burleson35 min
May 11, 11:31 PM CDTSevere Thunderstorm WarningEWXMedina64 min
May 11, 11:40 PM CDTTornado WarningHGXGrimes35 min
May 11, 11:49 PM CDTSevere Thunderstorm WarningHGXGrimes, Walker41 min
May 11, 11:56 PM CDTFlash Flood WarningEWXKinney, Maverick4 hr

The nearest sounding before it

Del Rio, TX (KDRT), launched 00:00Z, 1.5 hours before the alert went out and 236 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 1999-05-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3001 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 1999-05-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 3 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
3001 J/kg
Mixed-layer CIN
-32 J/kg
Mixed-layer LCL
1924 m above ground
0-6 km bulk shear
39 kt
0-1 km storm-relative helicity
3 m²/s²
0-3 km storm-relative helicity
148 m²/s²
Significant tornado parameter
0.1
Supercell composite
5.5

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.

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 11, 9:15 PM CDTSevere Thunderstorm WatchSPCBowie, Camp, Cass, Collin, Cooke, Dallas and 33 more4 hr
May 11, 10:45 PM CDTSevere Thunderstorm WatchSPCAngelina, Bowie, Camp, Cass, Cherokee, Delta and 18 more5 hr
May 12, 12:00 AM CDTSevere Thunderstorm WatchSPCAngelina, Grimes, Hardin, Jasper, Liberty, Montgomery and 12 more4 hr
May 12, 12:00 AM CDTSevere Thunderstorm WatchSPCAtascosa, Dimmit, Duval, Frio, Jim Wells, Kinney and 9 more5 hr
May 12, 4:30 AM CDTSevere Thunderstorm WatchSPCAransas, Bee, Calhoun, DeWitt, Duval, Goliad and 13 more6 hr

Nearby

Tornado Watches in Texas, 1999Every tornado watch 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.