

843 

WWUS20 KWNS 292255

SEL2

SPC WW 292255

MNZ000-WIZ000-LSZ000-300600-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 502

NWS STORM PREDICTION CENTER NORMAN OK

545 PM CDT THU AUG 29 2013



THE NWS STORM PREDICTION CENTER HAS ISSUED A



* SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

  CENTRAL AND NORTHERN MINNESOTA

  NORTHWEST WISCONSIN

  LAKE SUPERIOR



* EFFECTIVE THIS THURSDAY AFTERNOON AND FRIDAY MORNING FROM 545

  PM UNTIL 100 AM CDT.



* PRIMARY THREATS INCLUDE...

  SEVERAL LARGE HAIL EVENTS WITH A FEW VERY LARGE HAIL EVENTS TO 2

    INCHES IN DIAMETER POSSIBLE

  SEVERAL DAMAGING WIND GUSTS TO 70 MPH POSSIBLE

  A FEW TORNADOES POSSIBLE



THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 95

STATUTE MILES EAST AND WEST OF A LINE FROM 20 MILES EAST

NORTHEAST OF HIBBING MINNESOTA TO 45 MILES EAST OF SAINT CLOUD

MINNESOTA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU2).



PRECAUTIONARY/PREPAREDNESS ACTIONS...



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...TSTM NOW IN N CNTRL MN IS FORMING IN ZONE OF MAXIMUM

LOW-LVL CONFLUENCE ZONE NEAR INTERSECTION OF OUTFLOW BOUNDARY LEFT

BY EARLIER MCS /NOW IN WI/ AND NE-SW COLD FRONT ASSOCIATED WITH SW

ONT/NW MN UPR IMPULSE. THIS STORM...AND OTHERS FORMING FARTHER SE

ALONG THE OUTFLOW BOUNDARY...ARE EXPECTED TO CONTINUE

MOVING/DEVELOPING ESE THROUGH MID-EVE.

AMPLE DEEP SHEAR AND MOISTURE SHOULD REMAIN PRESENT FOR SUPERCELLS

CAPABLE OF SVR HAIL/WIND. IN ADDITION...A NON-ZERO THREAT WILL EXIST

FOR A TORNADO OR TWO...GIVEN THE PRESENCE OF A SUSTAINED SUPERCELL.

THIS THREAT SHOULD BE GREATEST OVER THE NEXT FEW HOURS IN ZONE OF

BACKED LOW-LVL FLOW ALONG OUTFLOW BOUNDARY...WHERE LOW-LVL

DESTABILIZATION WILL BE GREATEST...AND WHERE SWLY LLJ WILL INCREASE

AFTER SUNSET. THE OVERALL TORNADO THREAT SHOULD...HOWEVER...BE

LIMITED IN SPACE AND TIME.



AVIATION...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 550. MEAN STORM

MOTION VECTOR 28030.





...CORFIDI

