

514 

WWUS20 KWNS 272342

SEL2

SPC WW 272342

ARZ000-LAZ000-TXZ000-280700-



URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 82

NWS STORM PREDICTION CENTER NORMAN OK

635 PM CDT FRI MAR 27 2009



THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF



       SOUTHERN ARKANSAS

       NORTHWEST LOUISIANA

       NORTHEAST TEXAS



EFFECTIVE THIS FRIDAY NIGHT AND SATURDAY MORNING FROM 635 PM

UNTIL 200 AM CDT.



TORNADOES...HAIL TO 2.5 INCHES IN DIAMETER...THUNDERSTORM WIND

GUSTS TO 80 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE

AREAS.



THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 95 STATUTE

MILES EAST AND WEST OF A LINE FROM 15 MILES WEST NORTHWEST OF

LITTLE ROCK ARKANSAS TO 50 MILES WEST SOUTHWEST OF NATCHITOCHES

LOUISIANA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU2).



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.



OTHER WATCH INFORMATION...CONTINUE...WW 78...WW 79...WW 80...WW

81...



DISCUSSION...POWERFUL UPPER TROUGH AND ASSOCIATED 70-80 MID LEVEL

JET STREAK WILL CONTINUE TO SPREAD EAST ACROSS TX/OK AREAS THROUGH

TONIGHT AND LEND SUPPORT TO DEEP SURFACE CYCLOGENESIS FROM THE

ARKLATEX TO THE MS RIVER. AIR MASS AHEAD OF THIS PRONOUNCED SUPPORT

FOR STRONG UPWARD MOTION WAS MOIST AND SUFFICIENTLY UNSTABLE TO

SUPPORT ROBUST TSTM UPDRAFTS IN A REGIME CHARACTERIZED BY

STRENGTHENING DEEP-LAYER SHEAR AND INTENSE MESOSCALE FORCING NEAR

THE DEVELOPING LOW AND EWD ALONG WARM FRONT ACROSS SRN AR. CELLS

SHOULD CONTINUE TO GAIN STRENGTH NEAR THESE FEATURES...AS WELL AS

ALONG SURGING COLD FRONT NOW MOVING INTO ERN TX AND SERN OK. SHEAR

AND FORCING WILL BE MORE THAN ADEQUATE FOR UPDRAFT ROTATION AND

LONG-LIVED MESOCYCLONES. STORMS NEAR/EAST THE LOW CENTER...AND

TRACKING ALONG THE FRONT ACROSS AR WILL EXPERIENCE GREATEST LOW

LEVEL SHEAR AND HAVE THE POTENTIAL TO PRODUCE TORNADOES IN ADDITION

TO VERY LARGE HAIL. LINEAR FORCING WITH THE COLD FRONT MAY PROMOTE

EVENTUAL SQUALL LINE DEVELOPMENT WITH INCREASE IN WIDESPREAD WIND

THREAT POSSIBLY DEVELOPING LATER TONIGHT.



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

SURFACE AND ALOFT TO 2.5 INCHES. EXTREME TURBULENCE AND SURFACE

WIND GUSTS TO 70 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO

500. MEAN STORM MOTION VECTOR 24030.





...CARBIN

