

000 

WWUS20 KWNS 212203

SEL2

SPC WW 212203

SDZ000-220500-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 592

NWS STORM PREDICTION CENTER NORMAN OK

505 PM CDT SAT JUN 21 2008



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       CENTRAL AND SOUTHEAST SOUTH DAKOTA



EFFECTIVE THIS SATURDAY AFTERNOON FROM 505 PM UNTIL MIDNIGHT CDT.



HAIL TO 2.5 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 50

STATUTE MILES NORTH AND SOUTH OF A LINE FROM 25 MILES WEST

NORTHWEST OF PHILIP SOUTH DAKOTA TO 35 MILES NORTH NORTHEAST OF

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

THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU2).



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 589...WW 590...WW 591...



DISCUSSION...SCATTERED INTENSE THUNDERSTORMS HAVE DEVELOPED ALONG

AXIS OF INSTABILITY FROM CENTRAL INTO SOUTHEAST SD.  STRONG

EFFECTIVE SHEAR AND STEEP LAPSE RATES WILL PROMOTE A RISK OF

SUPERCELLS CAPABLE OF LARGE HAIL AND DAMAGING WINDS THROUGH THE

EVENING.



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

TO 2.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60

KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM

MOTION VECTOR 31030.





...HART

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