

634 

WWUS20 KWNS 232316

SEL4

SPC WW 232316

SDZ000-240300-



URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 474

NWS STORM PREDICTION CENTER NORMAN OK

615 PM CDT SAT AUG 23 2014



THE NWS STORM PREDICTION CENTER HAS ISSUED A



* TORNADO WATCH FOR PORTIONS OF

  A SMALL PART OF NORTH CENTRAL AND NORTHEAST SOUTH DAKOTA



* EFFECTIVE THIS SATURDAY EVENING FROM 615 PM UNTIL 1000 PM CDT.



* PRIMARY THREATS INCLUDE...

  A COUPLE TORNADOES POSSIBLE



THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 55 STATUTE

MILES EAST AND WEST OF A LINE FROM 30 MILES NORTH OF ABERDEEN

SOUTH DAKOTA TO 55 MILES SOUTH OF ABERDEEN SOUTH DAKOTA.  FOR A

COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE

UPDATE (WOUS64 KWNS WOU4).



PRECAUTIONARY/PREPAREDNESS ACTIONS...



REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR

TORNADOES AND 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.



&&



DISCUSSION...ISOLATED SUPERCELL WILL MOVE NWD ACROSS THE SURFACE

WARM FRONT...AND ADDITIONAL STORM DEVELOPMENT MAY OCCUR IN THE NEXT

COUPLE OF HOURS.  A TORNADO OR TWO WILL BE POSSIBLE IN THE ZONE OF

ENHANCED LOW-LEVEL SHEAR NEAR AND N OF THE BOUNDARY...GIVEN AT LEAST

WEAK SURFACE-BASED BUOYANCY AND BOUNDARY LAYER DEWPOINTS IN THE

UPPER 60S.



AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL

SURFACE AND ALOFT TO 1 INCH. EXTREME TURBULENCE AND SURFACE WIND

GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500.

MEAN STORM MOTION VECTOR 18025.





...THOMPSON



749 

WWUS20 KWNS 232316

SEL4

SPC WW 232316

SDZ000-240300-



URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 474

NWS STORM PREDICTION CENTER NORMAN OK

615 PM CDT SAT AUG 23 2014



THE NWS STORM PREDICTION CENTER HAS ISSUED A



* TORNADO WATCH FOR PORTIONS OF

  A SMALL PART OF NORTH CENTRAL AND NORTHEAST SOUTH DAKOTA



* EFFECTIVE THIS SATURDAY EVENING FROM 615 PM UNTIL 1000 PM CDT.



* PRIMARY THREATS INCLUDE...

  A COUPLE TORNADOES POSSIBLE



THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 55 STATUTE

MILES EAST AND WEST OF A LINE FROM 30 MILES NORTH OF ABERDEEN

SOUTH DAKOTA TO 55 MILES SOUTH OF ABERDEEN SOUTH DAKOTA.  FOR A

COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE

UPDATE (WOUS64 KWNS WOU4).



PRECAUTIONARY/PREPAREDNESS ACTIONS...



REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR

TORNADOES AND 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.



&&



DISCUSSION...ISOLATED SUPERCELL WILL MOVE NWD ACROSS THE SURFACE

WARM FRONT...AND ADDITIONAL STORM DEVELOPMENT MAY OCCUR IN THE NEXT

COUPLE OF HOURS.  A TORNADO OR TWO WILL BE POSSIBLE IN THE ZONE OF

ENHANCED LOW-LEVEL SHEAR NEAR AND N OF THE BOUNDARY...GIVEN AT LEAST

WEAK SURFACE-BASED BUOYANCY AND BOUNDARY LAYER DEWPOINTS IN THE

UPPER 60S.



AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL

SURFACE AND ALOFT TO 1 INCH. EXTREME TURBULENCE AND SURFACE WIND

GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500.

MEAN STORM MOTION VECTOR 18025.





...THOMPSON

