[MCD] SWOMCD

[Mesoscale Convective Discussions]

ACUS11 KWNS 261726
SWOMCD
SPC MCD 261726 
LAZ000-TXZ000-261830-

MESOSCALE DISCUSSION 2156
NWS STORM PREDICTION CENTER NORMAN OK
1226 PM CDT THU OCT 26 2006

AREAS AFFECTED...PORTIONS SE TX...SWRN LA.

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY 

VALID 261726Z - 261830Z

ADDITIONAL TSTMS ARE FCST TO DEVELOP IN WSW-ENE ALIGNED BAND FROM
MIDDLE TX COASTAL PLAIN ACROSS PORTIONS HOU METRO AREA...TO BETWEEN
ESF-LFT.  EMBEDDED SUPERCELLS ARE POSSIBLE WITH SLGT POTENTIAL FOR A
SHORT-LIVED TORNADO.  

SFC ANALYSIS SHOWS MARINE/WARM FRONT FROM OFFSHORE ATCHAFALAYA BAY
NWWD OVER CAMERON PARISH AND LOWER SABINE RIVER REGION.  THIS FRONT
SHOULD LIFT NWD THROUGH AFTERNOON...SPREADING MARITIME/TROPICAL AIR
MASS ACROSS MORE OF SRN LA.  SFC WINDS OVER MUCH OF THIS REGION ARE
SLY TO SSWLY...WITH SOME BACKING POSSIBLE OVER NEXT FEW HOURS AS
PRESSURES FALL IN WARM SECTOR OF DEEPENING OK CYCLONE. THIS WILL
MAINTAIN OR SLIGHTLY ENHANCE LOW LEVEL SHEAR/SRH...AS WELL AS
DEEP-LAYER SHEAR.  VWP AND RUC HODOGRAPHS INDICATE 0-1 KM SRH
INCREASING FROM AROUND 150-300 J/KG WITH EWD EXTENT...FROM MIDDLE TX
COAST INTO SWRN LA...ALONG WITH 0-6 KM SHEAR 30-40 KT. 

IN SUPPORT OF BOTH SVR POTENTIAL AND HEAVY RAIN THREAT...VERY RICH
LOW LEVEL MOISTURE IS EVIDENT WITH MID 70S F SFC DEW POINTS ANALYZED
IN INFLOW AIR MASS EMANATING FROM GULF COASTAL WATERS. THIS WILL
SUPPORT MLCAPES 1000-2000 J/KG SHIFTING EWD ACROSS AREA THROUGH
EARLY-MID AFTERNOON...AS SFC INSOLATION CONTINUES.  PW VALUES 2-2.25
INCHES ARE BASED ON MODIFIED CRP/LCH RAOBS...PAST SEVERAL HOURS OF
GPS DATA AND MODIFIED RUC SOUNDINGS.  HEAVY RAIN RATES 2-3
INCHES/HOUR WILL CONTINUE WITHIN THIS BAND...INCLUDING PORTIONS THAT
MAY BACKBUILD AND BECOME MORE DENSE WSW OF HOU.  CONTINUED TRAINING
OF ECHOES WILL ENHANCE HEAVY RAINFALL THREAT.

..EDWARDS.. 10/26/2006

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

ATTN...WFO...LCH...HGX...

29519556 30309449 30589340 30639259 30139250 29689300
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