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WWUS20 KWNS 221856

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ARZ000-OKZ000-230200-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 429

NWS STORM PREDICTION CENTER NORMAN OK

155 PM CDT MON JUL 22 2013



THE NWS STORM PREDICTION CENTER HAS ISSUED A



* SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

  ARKANSAS

  EASTERN OKLAHOMA



* EFFECTIVE THIS MONDAY AFTERNOON AND EVENING FROM 155 PM UNTIL

  900 PM CDT.



* PRIMARY THREATS INCLUDE...

  SEVERAL LARGE HAIL EVENTS WITH A FEW VERY LARGE HAIL EVENTS TO 2

    INCHES IN DIAMETER POSSIBLE

  SEVERAL DAMAGING WIND GUSTS TO 70 MPH POSSIBLE



THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 75

STATUTE MILES NORTH AND SOUTH OF A LINE FROM 15 MILES SOUTH OF

TULSA OKLAHOMA TO 45 MILES EAST OF PINE BLUFF ARKANSAS.  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.



&&



DISCUSSION...VERY UNSTABLE AND WEAKLY CAPPED AIRMASS HAS DEVELOPED

AMIDST OUTFLOW BOUNDARY SITUATED NW TO SE FROM NERN OK ACROSS SCNTRL

AR. CONTINUED CONVERGENCE AND HEATING ALONG THE BOUNDARY AND WITHIN

THE CORRIDOR OF INSTABILITY SHOULD SPUR ADDITIONAL TSTM DEVELOPMENT

THROUGH THE AFTERNOON AS A LOW AMPLITUDE SHORT WAVE TROUGH

APPROACHES THE REGION FROM KS. GIVEN DEGREE OF INSTABILITY AND

MODEST W-NWLY MID-LEVEL FLOW OF 25-30KT...EXPECT CHANCES FOR

ORGANIZATION AND WIND DAMAGE POTENTIAL TO INCREASE THROUGH THE

AFTERNOON AND INTO EARLY EVENING. IT REMAINS UNCLEAR WHETHER STORMS

WILL MERGE INTO A FORWARD PROPAGATING SYSTEM OR REMAIN

SEMI-DISCRETE. HOWEVER...GIVEN THE INCREASING CHANCES FOR STORM

DEVELOPMENT IN SUCH AN UNSTABLE ENVIRONMENT...A WATCH IS WARRANTED

AT THIS TIME.



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 550. MEAN STORM

MOTION VECTOR 30025.





...CARBIN

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