Tornado Watch 345

Issued

May 23, 2011, 2:30 PM CDT (19:30 UTC)

Expired

May 23, 2011, 10:00 PM CDT

In force

8 hr

Issued by

the Storm Prediction Center

Largest hail expected

3 in

Strongest gust expected

60 kt

The Vance AFB radar (KVNX), 116 km from the middle of the area, began a volume at 19:30 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

60%

One or more EF2 to EF5 tornadoes

50%

Ten or more severe wind reports

30%

One or more gusts of 65 knots or more

30%

Ten or more severe hail reports

80%

One or more hailstones of 2 inches or more

90%

Six or more combined severe hail and wind reports

90%

• Mesoscale Discussion 896May 23, 2:08 PM CDT
• Mesoscale Discussion 904May 23, 5:07 PM CDT
• Mesoscale Discussion 910May 23, 6:51 PM CDT
• Mesoscale Discussion 913May 23, 7:50 PM CDT
• Mesoscale Discussion 915May 23, 9:22 PM CDT

548 
WWUS20 KWNS 231934
SEL5
SPC WW 231934
OKZ000-TXZ000-240300-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 345
NWS STORM PREDICTION CENTER NORMAN OK
230 PM CDT MON MAY 23 2011

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

       WESTERN OKLAHOMA
       NORTHWEST TEXAS

EFFECTIVE THIS MONDAY AFTERNOON AND EVENING FROM 230 PM UNTIL
1000 PM CDT.

TORNADOES...HAIL TO 3 INCHES IN DIAMETER...THUNDERSTORM WIND
GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE
AREAS.

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 60 STATUTE
MILES EAST AND WEST OF A LINE FROM 25 MILES NORTHEAST OF ALVA
OKLAHOMA TO 40 MILES SOUTH SOUTHEAST OF ALTUS OKLAHOMA.  FOR A
COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE
UPDATE (WOUS64 KWNS WOU5).

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND 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.

OTHER WATCH INFORMATION...CONTINUE...WW 338...WW 339...WW
340...WW 341...WW 342...WW 343...WW 344...

DISCUSSION...TCU/INCIPIENT TSTM DEVELOPMENT IS IN PROGRESS ALONG
DRYLINE IN WRN OK SW OF CSM.  MODIFICATION OF 19Z OUN SOUNDING FOR
AIR MASS IMMEDIATELY E OF DRYLINE SUGGESTS THAT ENVIRONMENT IS
NEARLY UNCAPPED WITH MLCAPE OF 4000-5000 J/KG.  WHILE PASSAGE OF
SHORT WAVE TROUGH TO THE NE IS NOT PARTICULARLY WELL-TIMED...STRONG
DIABATIC HEATING W OF DRYLINE SHOULD SERVE TO FOSTER AT LEAST
ISOLATED STORM DEVELOPMENT THIS AFTERNOON INTO EVENING.
INITIALLY...VERY LARGE HAIL WILL BE THE PRIMARY HAZARD WITH MATURE
SUPERCELLS GIVEN THE LOCALLY HIGHER T-TD SPREADS AND WEAK LOW-LEVEL
FLOW.  THE POTENTIAL FOR TORNADOES WILL INCREASE THIS EVENING AS
LOW-LEVEL SHEAR STRENGTHENS AND LCL HEIGHTS LOWER.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 3 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
600. MEAN STORM MOTION VECTOR 27020.


...MEAD

Tornado Watches in Oklahoma, 2011Tornado Watches in Texas, 2011Every tornado 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.