Alert archive / Texas / Severe Thunderstorm Watches in 2002

Severe Thunderstorm Watch 80

April 8, 200213 counties in Texas

The Storm Prediction Center issued this severe thunderstorm watch at Apr 8, 2002, 3:00 AM CDT for 13 counties in Texas. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued
Apr 8, 2002, 3:00 AM CDT (08:00 UTC)
Expired
Apr 8, 2002, 8:00 AM CDT
In force
5 hr
Issued by
the Storm Prediction Center

Counties Austin County, TX, Brazoria County, TX, Calhoun County, TX, Colorado County, TX, Fort Bend County, TX, Galveston County, TX, Harris County, TX, Jackson County, TX, Liberty County, TX, Matagorda County, TX, Montgomery County, TX, Waller County, TX, Wharton County, TX

The radar

The Houston radar (KHGX), 80 km from the middle of the area, began a volume at 07:59 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

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

IssuedProductOfficeCountiesLasted
Apr 8, 4:25 AM CDTSevere Thunderstorm WarningCRPCalhoun, Victoria65 min
Apr 8, 6:23 AM CDTSevere Thunderstorm WarningHGXJackson, Matagorda37 min
Apr 8, 7:00 AM CDTSevere Thunderstorm WarningHGXBrazoria, Matagorda45 min
Apr 8, 7:45 AM CDTSevere Thunderstorm WarningHGXBrazoria, Galveston30 min

The nearest sounding before it

Corpus Christi, TX (KCRP), launched 00:00Z, 8.0 hours before the alert went out and 246 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, Corpus Christi, TX at 00:00Z on 2002-04-08Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2444 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, Corpus Christi, TX at 00:00Z on 2002-04-08The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 180 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
2444 J/kg
Mixed-layer CIN
-128 J/kg
Mixed-layer LCL
655 m above ground
0-6 km bulk shear
58 kt
0-1 km storm-relative helicity
180 m²/s²
0-3 km storm-relative helicity
182 m²/s²
Significant tornado parameter
1.5
Supercell composite
6.1

Open this sounding in Storm Lab

The text

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

000 
WWUS20 KWNS 080741
SEL0  
SPC WW 080735
TXZ000-CWZ000-081300-

URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 80
STORM PREDICTION CENTER NORMAN OK
235 AM CDT MON APR 8 2002

THE STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

   SOUTHEAST TEXAS                              
   COASTAL WATERS                     

EFFECTIVE THIS MONDAY MORNING FROM 300 AM UNTIL 800 AM CDT.

HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70
MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE SEVERE THUNDERSTORM WATCH AREA IS ALONG AND 55 STATUTE MILES
NORTH AND SOUTH OF A LINE FROM 35 MILES NORTHWEST OF PALACIOS TEXAS
TO 35 MILES NORTH OF GALVESTON TEXAS.

REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE
FAVORABLE FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH AREA. 
PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR THREATENING
WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS AND POSSIBLE
WARNINGS.  SEVERE THUNDERSTORMS CAN AND OCCASIONALLY DO PRODUCE
TORNADOES.

OTHER WATCH INFORMATION...THIS SEVERE THUNDERSTORM WATCH REPLACES
SEVERE THUNDERSTORM WATCH NUMBER 76.  WATCH NUMBER 76 WILL NOT BE
IN EFFECT AFTER 300 AM CDT.  CONTINUE...WW 77...WW 78...WW 79...

DISCUSSION...LARGE SCALE ASCENT WILL CONTINUE TO SUPPORT INCREASING
THUNDERSTORMS ACROSS SOUTHEAST TX THROUGH THE REMAINDER OF THE
NIGHT...AHEAD OF STRONG UPPER LOW.  THIS AREA REMAINS VERY UNSTABLE
ABOVE SHALLOW COLD POOL IN THE WAKE OF EXTENSIVE SQUALL LINE NOW
MOVING INTO SWRN LA.  A PRIMARY THREAT OF LARGE HAIL WILL THEREFORE
ACCOMANY STORMS AS THEY DEVELOP INTO THE WW.


AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 2 INCHES.  EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60
KNOTS.  A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500.  MEAN STORM
MOTION VECTOR 25035.


...EVANS

295,0963 303,0944 290,0944 281,0963

WWUS20 KWNS 080741
SEL0  
SPC WW 080735
TXZ000-CWZ000-081300-

URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 80
STORM PREDICTION CENTER NORMAN OK
235 AM CDT MON APR 8 2002

THE STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

   SOUTHEAST TEXAS                              
   COASTAL WATERS                     

EFFECTIVE THIS MONDAY MORNING FROM 300 AM UNTIL 800 AM CDT.

HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70
MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE SEVERE THUNDERSTORM WATCH AREA IS ALONG AND 55 STATUTE MILES
NORTH AND SOUTH OF A LINE FROM 35 MILES NORTHWEST OF PALACIOS TEXAS
TO 35 MILES NORTH OF GALVESTON TEXAS.

REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE
FAVORABLE FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH AREA. 
PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR THREATENING
WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS AND POSSIBLE
WARNINGS.  SEVERE THUNDERSTORMS CAN AND OCCASIONALLY DO PRODUCE
TORNADOES.

OTHER WATCH INFORMATION...THIS SEVERE THUNDERSTORM WATCH REPLACES
SEVERE THUNDERSTORM WATCH NUMBER 76.  WATCH NUMBER 76 WILL NOT BE
IN EFFECT AFTER 300 AM CDT.  CONTINUE...WW 77...WW 78...WW 79...

DISCUSSION...LARGE SCALE ASCENT WILL CONTINUE TO SUPPORT INCREASING
THUNDERSTORMS ACROSS SOUTHEAST TX THROUGH THE REMAINDER OF THE
NIGHT...AHEAD OF STRONG UPPER LOW.  THIS AREA REMAINS VERY UNSTABLE
ABOVE SHALLOW COLD POOL IN THE WAKE OF EXTENSIVE SQUALL LINE NOW
MOVING INTO SWRN LA.  A PRIMARY THREAT OF LARGE HAIL WILL THEREFORE
ACCOMANY STORMS AS THEY DEVELOP INTO THE WW.


AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 2 INCHES.  EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60
KNOTS.  A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500.  MEAN STORM
MOTION VECTOR 25035.


...EVANS

295,0963 303,0944 290,0944 281,0963

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 7, 8:00 PM CDTSevere Thunderstorm WatchSPCAtascosa, Bastrop, Bell, Burleson, Caldwell, Collin and 36 more5 hr
Apr 7, 11:00 PM CDTSevere Thunderstorm WatchSPCAngelina, Austin, Brazoria, Brazos, Colorado, Fort Bend and 14 more4 hr
Apr 8, 1:00 AM CDTSevere Thunderstorm WatchSPCAransas, Atascosa, Bee, Bexar, DeWitt, Frio and 12 more4 hr
Apr 8, 1:15 AM CDTSevere Thunderstorm WatchSPCChambers, Hardin, Jasper, Jefferson, Liberty, Newton and 4 more5 hr

Nearby

Severe Thunderstorm Watches in Texas, 2002Every severe thunderstorm watch in 2002

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.