[MCD] SWOMCD

Thu Nov 30 18:59:14 UTC 2006

ACUS11 KWNS 301901
SWOMCD
SPC MCD 301900 
TNZ000-MSZ000-ARZ000-LAZ000-302100-

MESOSCALE DISCUSSION 2249
NWS STORM PREDICTION CENTER NORMAN OK
0100 PM CST THU NOV 30 2006

AREAS AFFECTED...PORTIONS SRN/CENTRAL/ERN AR...NRN LA...NWRN
MS...EXTREME SWRN TN.

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 

VALID 301900Z - 302100Z

LINE OF SHALLOW CONVECTION NOW EVIDENT INVOF SFC COLD FRONT ACROSS
SWRN AR MAY BUILD INTO QUASI-LINEAR CONVECTIVE SYSTEM ACROSS SRN/ERN
AR...STRENGTHENING TO SVR LEVELS WITH DAMAGING GUSTS BEING MAIN
THREAT.  A FEW TORNADOES ALSO ARE POSSIBLE.  ACTIVITY MAY AFFECT
PORTIONS NRN LA...NERN MS AND PERHAPS EXTREME SWRN TN AS WELL.

18Z SFC MESOANSLYSIS SHOWS DEEPENING SFC LOW BETWEEN HOT-TXK...WHICH
SHOULD CONTINUE TO STRENGTHEN AS IT DRIFTS NEWD ROUGHLY ALONG I-30
THEN I-40 TOWARD LIT/MEM AREAS.  FRONTAL ZONE E OF THIS LOW HAS
SAGGED SWD THROUGH PORTIONS MEM...SGT AND LIT AREAS BUT MAY STALL
AND/OR RETREAT SLGTLY N PRIOR TO CYCLONE PASSAGE.  THIS FRONT SHOULD
MARK SHARP NRN BOUND TO SVR POTENTIAL...GIVEN STRONGLY STABLE SFC
AIR TO ITS N AND LACK OF COOLING ALOFT TO SUPPORT HAIL THREAT. 
BUOYANCY WILL REMAIN MRGL BECAUSE OF MIDLEVEL WARM LAYER --
INDICATED IN RAOBS...ACARS AND MODEL SOUNDINGS.  HOWEVER RELATIVELY
CLOUD-FREE WARM SECTOR WILL ALLOW CONTINUED SFC HEATING...WEAKENING
CINH...AND INCREASING MLCAPES TO AROUND 500 J/KG...BASED ON MODIFIED
RUC SOUNDINGS.

LOCALIZED SHEAR/VORTICITY ENHANCEMENT IS FCST ALONG FRONT E OF SFC
LOW...AND MESOSCALE AND DEEP-LAYER SHEAR PROFILES ARE FCST TO
INTENSIFY IN WARM SECTOR AS MID-UPPER CYCLONE EXITS SRN HIGH PLAINS.
 JUST ABOVE 500 MB...15-18Z WINDS INCREASED FROM 75-100 KT IN FWD
RAOBS...A TREND THAT WILL SHIFT ENEWD WITH TIME.  STRENGTHENING OF
LOW LEVEL WAA REGIME...INTENSIFICATION OF LLJ ABOVE SFC...AND
ISALLOBARICALLY FORCED BACKING OF WINDS AHEAD OF SFC LOW...ALL WILL
ACT TO ENLARGE WARM SECTOR HODOGRAPHS. EXPECT INCREASINGLY
FAVORABLE ENVIRONMENT FOR SUPERCELLS WHERE CONVECTIVE MODE CAN
REMAIN RELATIVELY DISCRETE.  EMBEDDED SUPERCELLS AND LEWP/BOW
CIRCULATIONS ALSO ARE POSSIBLE WITH MAIN CONVECTIVE BAND.

..EDWARDS.. 11/30/2006

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

ATTN...WFO...MEG...JAN...LZK...SHV...

32229280 33269281 34259283 34479266 34749214 35029050
35318940 34918910 33359035 32539081 32199134 