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URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 111

NWS STORM PREDICTION CENTER NORMAN OK

530 PM MDT MON MAR 26 2012



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       SOUTHERN NORTH DAKOTA

       WESTERN AND CENTRAL SOUTH DAKOTA



EFFECTIVE THIS MONDAY AFTERNOON AND TUESDAY MORNING FROM 530 PM

UNTIL 100 AM MDT.



HAIL TO 1.5 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 80

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



THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 85

STATUTE MILES EAST AND WEST OF A LINE FROM 75 MILES SOUTH

SOUTHWEST OF PHILIP SOUTH DAKOTA TO 20 MILES WEST NORTHWEST OF

BISMARCK NORTH DAKOTA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE

THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU1).



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...TSTMS ARE NOW FORMING ALONG SSW-NNE CONFLUENCE AXIS ON

SW SD/FAR NW NEB.  OTHER STORMS MAY FORM LATER THIS EVE ALONG

NE-MOVING DEEP WIND SHIFT NOW CROSSING NE WY.  DEVELOPMENT WILL BE

ASSISTED BY UPR DIVERGENCE/DCVA ASSOCIATED WITH POTENT UPR VORT

MOVING STEADILY ENE FROM CNTRL WY.  WHILE THE CURRENT CONVECTION IS

WITHIN DRY/DEEPLY MIXED ENVIRONMENT SPREADING NE FROM THE CNTRL/NRN

HI PLNS...POTENTIAL WILL EXIST FOR THE STORMS TO BECOME ROOTED

WITHIN ZONE OF RELATIVELY MORE MOIST AIR STREAMING NWWD ALONG

SHALLOW WARM FRONT BISECTING SD.  IF THIS OCCURS...UPSCALE

DEVELOPMENT INTO ONE OR TWO SMALL MCSS MAY OCCUR.  50+ KT LWR

TROPOSPHERIC FLOW MAY YIELD EMBEDDED BOWING SEGMENTS WITH HIGH

WIND...MARGINALLY SVR HAIL...AND POSSIBLY A BRIEF TORNADO THROUGH

LATE TNGT/EARLY TUE.



AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT

TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 70

KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 400. MEAN STORM

MOTION VECTOR 23045.





...CORFIDI

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