Alert archive / Texas / Tornado Warnings in 1990

Tornado Warning 7, NWS Austin/San Antonio, TX

May 18, 1990Williamson County, Texas

NWS Austin/San Antonio, TX issued this tornado warning at May 18, 1990, 12:41 PM CDT for Williamson County, Texas. It was in force for 49 min.

The area

The counties it named.

The facts

Issued
May 18, 1990, 12:41 PM CDT (17:41 UTC)
Expired
May 18, 1990, 1:30 PM CDT
In force
49 min
Issued by
NWS Austin/San Antonio, TX
Area
Whole counties

County Williamson County, TX

The radar

The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.

The nearest sounding before it

Stephenville/Cla, TX (KSEP), launched 12:00Z, 5.7 hours before the alert went out and 181 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, Stephenville/Cla, TX at 12:00Z on 1990-05-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 9 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, Stephenville/Cla, TX at 12:00Z on 1990-05-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 35 square meters per square second.19395878Sfc1 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
9 J/kg
Mixed-layer CIN
-320 J/kg
Mixed-layer LCL
1186 m above ground
0-6 km bulk shear
12 kt
0-1 km storm-relative helicity
35 m²/s²
0-3 km storm-relative helicity
119 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.0

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KAUS 181740
TORAUS
TXC491-181830-
 
BULLETIN - EBS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE AUSTIN TX
1241 PM CDT FRI MAY 18 1990
 
THE NATIONAL WEATHER SERVICE IN AUSTIN HAS ISSUED A
TORNADO WARNING EFFECTIVE UNTIL  130 PM CDT
FOR PEOPLE IN THE FOLLOWING LOCATIONS...
 
IN SOUTH CENTRAL TEXAS
 
   ...WILLIAMSON COUNTY
 
 
 
 
IF YOU ARE CAUGHT OUTSIDE...SEEK SHELTER IN A NEARBY REINFORCED
BUILDING.  AS A LAST RESORT...SEEK SHELTER IN A CULVERT...DITCH
OR LOW SPOT AND COVER YOUR HEAD WITH YOUR HANDS.

The office that day

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

IssuedProductOfficeCountiesLasted
May 18, 1:28 PM CDTTornado WarningEWXWilliamson62 min
May 18, 1:55 PM CDTSevere Thunderstorm WarningEWXBurnet50 min
May 18, 4:36 PM CDTTornado WarningEWXCaldwell, Hays69 min

Nearby

Tornado Warnings in Texas, 1990Every tornado warning in 1990Tornadoes in 1990

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.