[MCD] SWOMCD

[MCD at goshenarc.org]

ACUS11 KWNS 091022
SWOMCD
SPC MCD 091022 
ALZ000-FLZ000-MSZ000-LAZ000-091145-

MESOSCALE DISCUSSION 2522
NWS STORM PREDICTION CENTER NORMAN OK
0422 AM CST THU DEC 09 2004

AREAS AFFECTED...SERN MS...SWRN AL...EXTREME WRN FL PNHDL AND
EXTREME ERN LA

CONCERNING...SEVERE THUNDERSTORM POTENTIAL 

VALID 091022Z - 091145Z

TSTMS HAVE BECOME MORE ORGANIZED FROM CNTRL MS SWD INTO ERN LA SINCE
09Z.  A BOW ECHO HAS FORMED OVER SMITH COUNTY MS AND IS MOVING ENEWD
AROUND 40 KTS. MESOANALYSIS SUGGESTS THAT THIS STORM IS RIDING
ALONG AN E-W WARM FRONT AND THERE IS EVIDENCE THAT A SUB-SYNOPTIC
LOW IS ASSOCIATED WITH THE STORM.  EXTRAPOLATION HAS THE STORM VCNTY
KMEI BY 1045Z AND INTO WRN AL AFTER 1115Z.  A TORNADO WATCH MAY
BECOME NECESSARY IN THE NEXT HOUR ACROSS PARTS OF CNTRL AL. 

VWP TIME SERIES FROM SLIDELL AND BRANDON SHOW THAT THE FLOW IN THE
LOW-MID LEVELS IS BEGINNING TO BECOME MORE UNIDIRECTIONAL...THUS THE
PROPENSITY FOR TSTMS TO BOW.  IT IS CONCEIVABLE THAT TSTMS WILL
CONTINUE TO GENERATE WITHIN A BROADER BAND OF CONVECTION THROUGH THE
NEXT SEVERAL HOURS...THEN MOVE EWD INTO CNTRL/SWRN AL AND THE WRN FL
PNHDL. DOWNSTREAM AIR MASS HAS DESTABILIZED AND IT IS REASONABLE TO
ASSUME THAT STORMS WILL BE NEARLY SURFACE BASED AND DAMAGING WINDS
WILL BE POSSIBLE.  IF THE SUB-SYNOPTIC LOW INTENSIFIES...LOW LEVEL
SHEAR IS APT TO BE STRONGER INTO PARTS OF CNTRL AL AND TORNADOES
WILL ALSO BE A THREAT. 

HIGHER PROBABILITIES FOR SEVERE WEATHER WILL LIKELY OCCUR ENEWD FROM
CNTRL MS INTO CNTRL AL WHERE THE STRONGEST LOW LEVEL SHEAR AND LARGE
SCALE ASCENT IS EXPECTED THROUGH MID-MORNING.  FARTHER S...
TENDENCIES FOR THE SHEAR TO DECREASE WILL LIKELY KEEP THE SEVERE
THREATS MARGINAL OR ISOLD.

..RACY.. 12/09/2004

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...BMX...MOB...JAN...LIX...

32508930 32908643 30558701 29038870 29389005 

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