

090 

WWUS20 KWNS 042152

SEL7

SPC WW 042152

MNZ000-SDZ000-050600-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 597

NWS STORM PREDICTION CENTER NORMAN OK

445 PM CDT MON JUL 4 2011



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       A SMALL PART OF WEST CENTRAL MINNESOTA

       SOUTHWEST THROUGH CENTRAL TO NORTHEAST SOUTH DAKOTA



EFFECTIVE THIS MONDAY AFTERNOON AND TUESDAY MORNING FROM 445 PM

UNTIL 100 AM CDT.



HAIL TO 3 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70

MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.



THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 100

STATUTE MILES EAST AND WEST OF A LINE FROM 35 MILES NORTH

NORTHWEST OF ABERDEEN SOUTH DAKOTA TO 80 MILES SOUTH SOUTHWEST OF

PHILIP SOUTH DAKOTA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE

THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU7).



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.



OTHER WATCH INFORMATION...CONTINUE...WW 593...WW 594...WW

595...WW 596...



DISCUSSION...TSTMS EXPECTED TO DEVELOP/INCREASE INVOF WEAK SFC WAVE

NEAR THE BLACK HILLS IN THE NEXT COUPLE HOURS...AND...A BIT

LATER...NEWD ALONG WEAK COLD FRONT EXTENDING NNE TO THE MBG AREA.

WHILE MAGNITUDE OF DEEP SHEAR WILL REMAIN RATHER MODEST /25-30

KTS/...IT WILL CONTAIN A COMPARATIVELY LARGE LOW LVL DIRECTIONAL

COMPONENT.  COUPLED WITH STEEP LOW TO MID LVL LAPSE RATES AND FAIRLY

RICH MOISTURE /DEWPOINTS IN THE LWR 70S F WITH PW AROUND 1

INCH/...SETUP COULD YIELD A FEW STRONG SUPERCELLS WITH VERY LARGE

HAIL...DMGG WIND...AND PERHAPS A TORNADO BEFORE ACTIVITY EVOLVES

INTO A COMPLEX MCS LATER THIS EVE.  A THREAT FOR DMGG WIND AND SOME

HAIL MAY PERSIST THROUGH LATE TNGT AS THE MCS MOVES GENERALLY ESE TO

SE...POSSIBLY WITH EMBEDDED BOWING SEGMENTS.



AVIATION...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 550. MEAN STORM

MOTION VECTOR 29020.





...CORFIDI

