

000 

WWUS20 KWNS 282102

SEL3

SPC WW 282102

KSZ000-NEZ000-290500-



URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 83

NWS STORM PREDICTION CENTER NORMAN OK

400 PM CDT WED MAR 28 2007



THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF



       WESTERN KANSAS

       EXTREME SOUTHWEST NEBRASKA



EFFECTIVE THIS WEDNESDAY AFTERNOON FROM 400 PM UNTIL MIDNIGHT 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 65 STATUTE

MILES EAST AND WEST OF A LINE FROM 15 MILES NORTHWEST OF MCCOOK

NEBRASKA TO 5 MILES EAST SOUTHEAST OF LIBERAL KANSAS.  FOR A

COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE

UPDATE (WOUS64 KWNS WOU3).



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 80...WW 81...WW 82...



DISCUSSION...LOW-LEVEL MOISTURE /BOUNDARY LAYER DEWPOINTS OF 56-62

F/ CONTINUES TO SURGE NWD/NNWWD INTO WRN KS FROM OK...TO THE E OF A

CONFLUENCE BOUNDARY FROM W OF LBL TO NEAR GLD.  THE DEEPER MIXED

LAYER AND MUCH DRIER BOUNDARY LAYER IS LOCATED TO THE W ACROSS ERN

CO.  THE SURFACE MOISTURE GRADIENT MAY TEND TO CONSOLIDATE THROUGH

THE EVENING ACROSS EXTREME WRN KS...PROVIDING A FOCUS FOR STORM

INITIATION.  THE MOISTENING BOUNDARY LAYER AND TEMPERATURES IN THE

LOW-MID 70S WILL SUPPORT STRONG INSTABILITY /MLCAPE VALUES IN EXCESS

OF 2000 J/KG/.  AT THE SAME TIME...VERTICAL SHEAR WILL BECOME

INCREASINGLY FAVORABLE FOR SUPERCELLS INTO THIS EVENING.  GIVEN THAT

THE INITIAL DEVELOPMENT SHOULD BE DISCRETE SUPERCELLS ACROSS WRN

KS...WITH THE POTENTIAL FOR VERY LARGE HAIL AND A COUPLE OF STRONG

TORNADOES.  LATER THIS EVENING INTO TONIGHT...STORMS MAY GRADUALLY

MERGE INTO A LARGER N-S CONVECTIVE BAND WITH MORE OF A DAMAGING WIND

AND LARGE HAIL THREAT.



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

500. MEAN STORM MOTION VECTOR 21040.





...THOMPSON

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