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730 

WWUS20 KWNS 082304

SEL3

SPC WW 082304

MNZ000-NDZ000-SDZ000-090600-



URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 613

NWS STORM PREDICTION CENTER NORMAN OK

605 PM CDT FRI JUL 8 2011



THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF



       EAST-CENTRAL MINNESOTA

       SOUTHEAST NORTH DAKOTA

       NORTHEAST SOUTH DAKOTA



EFFECTIVE THIS FRIDAY NIGHT AND SATURDAY MORNING FROM 605 PM

UNTIL 100 AM CDT.



TORNADOES...HAIL TO 2 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 NORTH AND SOUTH OF A LINE FROM 40 MILES WEST OF JAMESTOWN

NORTH DAKOTA TO 55 MILES SOUTH OF DETROIT LAKES MINNESOTA.  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 610...WW 611...WW 612...



DISCUSSION...TSTMS HAVE DEVELOPED SEWD ALONG WARM FRONT FROM NW OF

JMS TO NE ABR WITHIN A NARROW CORRIDOR OF HIGHER BOUNDARY-LAYER

MOISTURE CONTENT AND MLCAPE OF 2000-2500 J/KG.  DEEP-LAYER VERTICAL

SHEAR DECREASES WITH EWD EXTENT ACROSS THE WATCH AREA WHICH MAY TEND

TO LIMIT MORE ROBUST SUPERCELL STRUCTURES.  NONETHELESS...THE

CO-LOCATION OF 200 J/KG 0-3 KM MLCAPE AND AMBIENT VORTICITY INVOF OF

SURFACE BOUNDARY WILL SUPPORT LOW-LEVEL UPDRAFT STRETCHING/ROTATION

WITH AN ATTENDANT RISK FOR A COUPLE TORNADOES.



AVIATION...TORNADOES AND 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 29020.





...MEAD

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