[MCD] SWOMCD

[Mesoscale Convective Discussions]

ACUS11 KWNS 122154
SWOMCD
SPC MCD 122154 
LAZ000-TXZ000-122330-

MESOSCALE DISCUSSION 0042
NWS STORM PREDICTION CENTER NORMAN OK
0354 PM CST THU JAN 12 2006

AREAS AFFECTED...SERN TX

CONCERNING...SEVERE THUNDERSTORM POTENTIAL 

VALID 122154Z - 122330Z

TSTMS ARE EXPECTED TO BECOME INCREASINGLY NUMEROUS LATE THIS
AFTERNOON AND ESPECIALLY THIS EVENING. CONVECTIVE TRENDS WILL BE
MONITORED FOR A POSSIBLE WW.

RADAR AND LIGHTNING DATA INDICATE THAT LARGELY ELEVATED CONVECTION
IS ATTEMPTING TO BECOME MORE SURFACE-BASED NEAR HOU AS OF 2135Z. 
CONSIDERABLE CLOUDINESS HAS LIMITED DAYTIME HEATING WITH
TEMPERATURES OF 70-75 F.  HOWEVER...A MOISTENING BOUNDARY-LAYER
COUPLED WITH INCREASED LARGE-SCALE FORCING FOR ASCENT ASSOCIATED
WITH A SHORTWAVE TROUGH MOVING THROUGH THE HILL COUNTRY ARE LIKELY
ERODING CAP OBSERVED ON 12Z REGIONAL SOUNDINGS.

DESPITE SOME WEAKNESSES IN WIND SPEED THROUGH THE 2-6 KM
LAYER...CURRENT LEDBETTER TX PROFILER INDICATES RELATIVELY STRONG
LOW-LEVEL VEERING WITH 40-45 KTS OF EFFECTIVE BULK SHEAR.  GIVEN
MUCAPES OF AROUND 1000 J/KG...POTENTIAL WILL EXIST FOR
ORGANIZED/ROTATING UPDRAFTS SHOULD STORMS BECOME ROOTED IN
BOUNDARY-LAYER.

CONVECTIVE EVOLUTION REMAINS SOMEWHAT UNCERTAIN ATTM OWING TO THE
ABSENCE OF ANY WELL-DEFINED LOW-LEVEL BOUNDARY TO FOCUS CONVECTIVE
DEVELOPMENT.  LATEST SHORT-TERM MODEL GUIDANCE DOES SUGGEST THAT
TSTMS WILL BECOME MORE NUMEROUS LATE THIS AFTERNOON AND MORE SO THIS
EVENING ACROSS FAR ERN TX WITHIN ZONE OF INCREASING LOW-LEVEL WAA
AHEAD OF STRONGER UPSTREAM TROUGH CURRENTLY MOVING SEWD TOWARD THE
RED RIVER VALLEY.

..MEAD.. 01/12/2006

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

ATTN...WFO...LCH...SHV...HGX...FWD...

29409542 29599609 30429651 31219617 31789518 31959444
31589381 30829364 29889400 

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