

145 

WWUS20 KWNS 012000

SEL8

SPC WW 012000

MNZ000-NDZ000-SDZ000-020300-



URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 558

NWS STORM PREDICTION CENTER NORMAN OK

300 PM CDT SUN AUG 1 2010



THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF



       CENTRAL AND WEST CENTRAL MINNESOTA

       EXTREME SOUTHEAST NORTH DAKOTA

       NORTHEAST SOUTH DAKOTA



EFFECTIVE THIS SUNDAY AFTERNOON AND EVENING FROM 300 PM UNTIL

1000 PM 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 50 STATUTE

MILES NORTH AND SOUTH OF A LINE FROM 10 MILES SOUTH OF SAINT

CLOUD MINNESOTA TO 50 MILES NORTHWEST OF WATERTOWN SOUTH DAKOTA.

FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH

OUTLINE UPDATE (WOUS64 KWNS WOU8).



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.



DISCUSSION...SURFACE-BASED THUNDERSTORM DEVELOPMENT IS ANTICIPATED

IN THE NEXT 1-2 HOURS ALONG THE SURFACE WARM FRONT THAT HAS BEEN

MOVING SLOWLY NWD ACROSS NE SD/SE ND AND W CENTRAL MN...NEAR THE SRN

EDGE OF THE ONGOING E-W BAND OF STORMS.  CONVECTION IS THEN EXPECTED

TO INCREASE IN COVERAGE WHILE SPREADING ESEWD TOWARD CENTRAL MN THIS

EVENING.  DEEP-LAYER AND LOW-LEVEL VERTICAL SHEAR ARE FAVORABLE FOR

SUPERCELLS ALONG THE WARM FRONT...WHERE MLCAPE AOA 2000 J/KG

COINCIDES WITH BOUNDARY LAYER DEWPOINTS NEAR 70 F.  A COUPLE OF

TORNADOES WILL BE POSSIBLE...ALONG WITH LARGE HAIL AND DAMAGING

WINDS.



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.





...THOMPSON

