

043 

WWUS20 KWNS 180058

SEL9

SPC WW 180058

SDZ000-180700-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 169

NWS STORM PREDICTION CENTER NORMAN OK

800 PM CDT FRI MAY 17 2013



THE NWS STORM PREDICTION CENTER HAS ISSUED A



* SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

  CENTRAL SOUTH DAKOTA



* EFFECTIVE THIS FRIDAY NIGHT AND SATURDAY MORNING FROM 800 PM

  UNTIL 200 AM CDT.



* PRIMARY THREATS INCLUDE...

  SEVERAL DAMAGING WIND GUSTS TO 70 MPH POSSIBLE

  SEVERAL LARGE HAIL EVENTS TO 1.5 INCHES IN DIAMETER POSSIBLE



THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 70

STATUTE MILES EAST AND WEST OF A LINE FROM 50 MILES NORTH

NORTHWEST OF PIERRE SOUTH DAKOTA TO 60 MILES SOUTH SOUTHWEST OF

CHAMBERLAIN SOUTH DAKOTA.  FOR A COMPLETE DEPICTION OF THE WATCH

SEE THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU9).



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.



&&



OTHER WATCH INFORMATION...CONTINUE...WW 166...WW 167...WW 168...



DISCUSSION...A MESOSCALE CONVECTIVE SYSTEM ACROSS FAR SOUTH-CENTRAL

SD WILL LIKELY CONTINUE TO ORGANIZE AND OTHERWISE EXPAND/POTENTIALLY

ACCELERATE EAST-NORTHEASTWARD ACROSS MUCH OF CENTRAL SD THIS

EVENING. THIS WILL BE WITH AID OF AN INCREASINGLY STRONG SOUTHERLY

LOW LEVEL JET. RELATIVELY STEEP LAPSE RATES AND MODERATE VERTICAL

SHEAR ARE NOTED IN 00Z OBSERVED SOUNDINGS FROM RAPID CITY AND

ABERDEEN. DAMAGING WINDS/BOUTS OF SEVERE HAIL WILL BE POSSIBLE

TONIGHT.



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

TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60

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

MOTION VECTOR 24035.





...GUYER

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