[MCD] SWOMCD

[MCD at goshenarc.org]

ACUS11 KWNS 261605
SWOMCD
SPC MCD 261605 
TXZ000-261800-

MESOSCALE DISCUSSION 0398
NWS STORM PREDICTION CENTER NORMAN OK
1005 AM CST SAT MAR 26 2005

AREAS AFFECTED...S CNTRL...SE TX

CONCERNING...SEVERE THUNDERSTORM POTENTIAL 

VALID 261605Z - 261800Z

SEVERE THREAT CONTINUES...NEW WW LIKELY WILL BE NEEDED EAST OF WW 85
BY EARLY AFTERNOON.

SURFACE COLD FRONT CONTINUES TO SLOWLY ADVANCE SOUTHWARD THROUGH
TEXAS...AND IS NOW SOUTH OF SHREVEPORT/LUFKIN/COLLEGE STATION/ AND
SAN ANTONIO...WITH A SHALLOWER COLD SURGE NOSING INTO UPPER TEXAS
COASTAL AREAS. HOWEVER...ABOVE FRONTAL INVERSION...WEAK SOUTHERLY
LOW-LEVEL FLOW PERSISTS IN ADVANCE OF STRONG DIGGING UPPER TROUGH
ACROSS THE SOUTHERN ROCKIES...AND THIS IS MAINTAINING VERY MOIST
POTENTIALLY UNSTABLE ENVIRONMENT.

LARGE-SCALE ASCENT ASSOCIATED WITH LOW/MID-LEVEL WARM ADVECTION
REGIME...BENEATH DIFLUENT AND DIVERGENT UPPER FLOW FIELD DOWNSTREAM
OF TROUGH...IS SUPPORTING BROAD RAIN SHIELD WITH EMBEDDED
THUNDERSTORM ACTIVITY ACROSS CENTRAL/NORTHEAST TEXAS.  STRONGEST
FORCING APPEARS IN BAND APPROACHING INTERSTATE 35...NORTHWEST OF SAN
ANTONIO INTO THE WACO AREAS.  THROUGH EARLY AFTERNOON...THIS WILL
GRADUALLY SHIFT ACROSS THE INTERSTATE 35 CORRIDOR...LIKELY REACHING
THE TYLER/LONGVIEW/LUFKIN AREAS SOUTHWARD THROUGH COLLEGE STATION
INTO AREAS EAST OF SAN ANTONIO BY 21Z. 

MORE NOTABLE INCREASE IN SEVERE THREAT MAY OCCUR TOWARD THE 20-21Z
TIME FRAME...AS HEATED BOUNDARY LAYER AIR MASS FROM SOUTH OF FRONT
BEGINS TO FEED INTO ACTIVITY. WITH MUCH OF ACTIVITY BASED ABOVE
RELATIVELY SHARP FRONTAL INVERSION...LARGE HAIL MAY BE PRIMARY
THREAT.  HOWEVER...CELLS ON SOUTHERN FLANK OF ACTIVITY LIKELY WILL
BECOME INCREASINGLY ROOTED IN BOUNDARY LAYER NEAR FRONT...IN AREA
BETWEEN SAN ANTONIO/AUSTIN/VICTORIA BY LATE AFTERNOON...WHERE/WHEN
RISK FOR TORNADOES MAY INCREASE.

..KERR.. 03/26/2005

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

ATTN...WFO...LCH...SHV...HGX...FWD...CRP...EWX...

30049878 31269783 31929689 32219617 32299546 32049454
31489445 30539472 29959536 29189667 28679767 28679912
29069959 29429928 

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