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000 

WWUS20 KWNS 201518

SEL6

SPC WW 201518

ALZ000-GAZ000-202300-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 546

NWS STORM PREDICTION CENTER NORMAN OK

1020 AM CDT FRI JUL 20 2007



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       NORTHERN AND CENTRAL ALABAMA

       WESTERN GEORGIA



EFFECTIVE THIS FRIDAY MORNING AND EVENING FROM 1020 AM UNTIL 600

PM 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 85

STATUTE MILES EAST AND WEST OF A LINE FROM 50 MILES NORTH OF

BIRMINGHAM ALABAMA TO 35 MILES SOUTH OF AUBURN ALABAMA.  FOR A

COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE

UPDATE (WOUS64 KWNS WOU6).



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...LINE OF STRONG/SEVERE STORMS CONTINUE MOVING SSEWD AT

AROUND 30 KT.  ACTIVITY IS MOVING INTO AN INSTABILITY AXIS WHERE

MORNING HEATING HAS BROUGHT ML PARCEL CAPE TO BETWEEN 1500-2000

J/KG.  ANALYSIS OF 13Z RUC SOUNDINGS SUPPORT STEEP LAPSE RATES TO

3KM ARE AROUND 8C/KM WHICH INDICATES POTENTIAL FOR DAMAGING WINDS

AND HAIL.



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 450. MEAN STORM

MOTION VECTOR 30030.





...MCCARTHY

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