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452 

WWUS20 KWNS 310149

SEL9

SPC WW 310149

ARZ000-OKZ000-310900-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 69

NWS STORM PREDICTION CENTER NORMAN OK

850 PM CDT SAT MAR 30 2013



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       NORTHWEST ARKANSAS

       EASTERN OKLAHOMA



EFFECTIVE THIS SATURDAY NIGHT AND SUNDAY MORNING FROM 850 PM

UNTIL 400 AM CDT.



HAIL TO 2 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 70

STATUTE MILES EAST AND WEST OF A LINE FROM 40 MILES SOUTH

SOUTHEAST OF MCALESTER OKLAHOMA TO 35 MILES NORTH NORTHWEST OF

FAYETTEVILLE ARKANSAS.  FOR A COMPLETE DEPICTION OF THE WATCH SEE

THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU9).



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 66...WW 68...



DISCUSSION...TSTMS HAVE RECENTLY INCREASED IN COVERAGE AND INTENSITY

NEAR AND N OF TULSA IN ADVANCE OF A COLD FRONT SETTLING SWD THROUGH

NRN OK.  AMBIENT AIR MASS REMAINS RELATIVELY WARM AND MOIST WITH

MLCAPE ESTIMATED AROUND 1000 J/KG.  MOREOVER...THE TULSA VAD HAS

SHOW A STEADY STRENGTHENING OF SLY WINDS BELOW 1 KM WHICH IS

RESULTING IN AN ENLARGED HODOGRAPH WITH MORE THAN SUFFICIENT SHEAR

FOR SUPERCELLS.  WHILE A BRIEF TORNADO IS POSSIBLE...LARGE HAIL AND

DAMAGING WINDS WILL BE THE PRIMARY HAZARDS AS STORMS SPREAD SEWD

ACROSS THE WATCH AREA.



AVIATION...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 500. MEAN STORM

MOTION VECTOR 31025.





...MEAD

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