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524 

WWUS20 KWNS 152231

SEL6

SPC WW 152231

NDZ000-160500-



URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 486

NWS STORM PREDICTION CENTER NORMAN OK

530 PM CDT SUN JUL 15 2012



THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF



       NORTHERN NORTH DAKOTA



EFFECTIVE THIS SUNDAY AFTERNOON FROM 530 PM UNTIL MIDNIGHT CDT.



TORNADOES...HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND

GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE

AREAS.



THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 50 STATUTE

MILES NORTH AND SOUTH OF A LINE FROM 75 MILES WEST OF MINOT NORTH

DAKOTA TO 25 MILES EAST NORTHEAST OF DEVILS LAKE NORTH DAKOTA.

FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH

OUTLINE UPDATE (WOUS64 KWNS WOU6).



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...VISIBLE IMAGERY SHOWS DEEPENING CONVECTION ALONG A N-S

SURFACE TROUGH ACROSS WRN ND...AS WELL AS NEAR THE SURFACE LOW IN NW

ND.  IT APPEARS THAT CONVECTIVE INHIBITION HAS WEAKENED ENOUGH TO

SUPPORT THUNDERSTORM DEVELOPMENT BY 23-00Z...WITH STORMS EXPECTED TO

MOVE GENERALLY EWD NEAR THE INTERNATIONAL BORDER.  BOUNDARY LAYER

MOISTURE AND LOW-LEVEL SHEAR ARE MAXIMIZED NEAR THE SURFACE WARM

FRONT...WHERE DEEP-LAYER SHEAR AND CAPE FAVOR SUPERCELLS.  THERE

WILL BE A RISK FOR A TORNADO OR TWO WITH DISCRETE STORMS INTERACTING

WITH THE WARM FRONT THIS EVENING...AND THE THREAT FOR LARGE

HAIL/DAMAGING WINDS WILL PERSIST INTO TONIGHT.



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

SURFACE AND ALOFT TO 2 INCHES. EXTREME TURBULENCE AND SURFACE

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

550. MEAN STORM MOTION VECTOR 26025.





...THOMPSON

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