Severe Thunderstorm Watch 4

Issued

Jan 9, 2011, 2:11 AM CST (08:11 UTC)

Expired

Jan 9, 2011, 5:49 AM CST

In force

4 hr

Issued by

the Storm Prediction Center

Largest hail expected

1 in

Strongest gust expected

60 kt

Counties Aransas County, TX, Calhoun County, TX, Duval County, TX, Jim Wells County, TX, Kleberg County, TX, Nueces County, TX, Refugio County, TX, San Patricio County, TX

The Corpus Christi radar (KCRP), 32 km from the middle of the area, began a volume at 08:14 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.

Two or more tornadoes

20%

One or more EF2 to EF5 tornadoes

5%

Ten or more severe wind reports

30%

One or more gusts of 65 knots or more

20%

Ten or more severe hail reports

5%

One or more hailstones of 2 inches or more

5%

Six or more combined severe hail and wind reports

50%

• Mesoscale Discussion 10Jan 9, 1:28 AM CST

118 
WWUS20 KWNS 090809
SEL4
SPC WW 090809
TXZ000-CWZ000-091300-

URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 4
NWS STORM PREDICTION CENTER NORMAN OK
210 AM CST SUN JAN 9 2011

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

       A SMALL PART OF SOUTH CENTRAL TEXAS AND THE MIDDLE TX COAST
       COASTAL WATERS

EFFECTIVE THIS SUNDAY MORNING FROM 210 AM UNTIL 700 AM CST.

HAIL TO 1 INCH IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70
MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 35
STATUTE MILES NORTH AND SOUTH OF A LINE FROM 45 MILES WEST
SOUTHWEST OF ALICE TEXAS TO 65 MILES EAST NORTHEAST OF CORPUS
CHRISTI TEXAS.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE
ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU4).

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.

DISCUSSION...AN ORGANIZED QLCS WILL MOVE EWD/ENEWD ACROSS S TX TO
THE MIDDLE TX COAST IN ADVANCE OF AN EJECTING MIDLEVEL TROUGH AND
ASSOCIATED SURFACE LOW.  THE MAIN SEVERE THREAT CORRIDOR WILL BE
ALONG THE WARM FRONT/INSTABILITY GRADIENT WHERE NEAR SURFACE-BASED
INSTABILITY WILL COINCIDE WITH STRONG VERTICAL SHEAR.  DAMAGING
WINDS WITH BOWING SEGMENTS SHOULD BE THE MAIN THREAT...THOUGH AN
ISOLATED TORNADO CANNOT BE RULED OUT WHERE STORMS INTERACT WITH THE
WARM FRONT...WHICH WILL MOVE CLOSE TO CRP BEFORE THE CONVECTION
REACHES THE COAST AROUND 11Z.

AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 1 INCH. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60 KNOTS.
A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM MOTION
VECTOR 25040.


...THOMPSON

Severe Thunderstorm Watches in Texas, 2011Every severe thunderstorm watch in 2011

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.