[MCD] SWOMCD

[MCD at goshenarc.org]

ACUS11 KWNS 251835
SWOMCD
SPC MCD 251834 
TXZ000-OKZ000-252000-

MESOSCALE DISCUSSION 0683
NWS STORM PREDICTION CENTER NORMAN OK
0134 PM CDT MON APR 25 2005

AREAS AFFECTED...CENTRAL AND N-CENTRAL TX INCLUDING DFW METRO AREA

CONCERNING...SEVERE THUNDERSTORM POTENTIAL 

VALID 251834Z - 252000Z

CENTRAL AND N-CENTRAL TX IS BEING MONITORED FOR CONVECTIVE
INITIATION AND A POSSIBLE TORNADO WATCH THIS AFTERNOON. CURRENT
TRENDS SUGGEST THREAT OF A FEW SUPERCELL STORMS WITH VERY LARGE HAIL
/IN EXCESS OF 2" DIAMETER/ AND ISOLATED TORNADOES. 

SFC PATTERN AT 1830Z FEATURES A DEEPENING SFC LOW OVER FAR SWRN OK
WITH A CONFLUENCE AXIS/DEVELOPING DRYLINE EXTENDING SWD FROM SPS TO
BWD.  MEANWHILE...A MESOSCALE COLD POOL EXISTS EAST OF I-35 AND
NORTH OF I-20 IN ASSOCIATION WITH THE CONTINUATION OF WEAK ELEVATED
THUNDERSTORM ACTIVITY THAT CONTINUES TO TRACK EWD. AXIS OF
ONGOING...STRONG SFC HEATING BETWEEN THE FORMING DRYLINE AND WRN
PERIPHERY OF OUTFLOW BOUNDARY SHOULD PROVIDE DESTABILIZATION
NECESSARY FOR THUNDERSTORM DEVELOPMENT BY LATE AFTERNOON. CONTINUED
SLY LOW-LEVEL MOISTURE RETURN SHOULD ALLOW DEWPOINTS TO RISE INTO
THE UPPER 50S TO NEAR 60. THESE FACTORS WILL LEAD TO MUCAPE VALUES
UP TO 2000 J/KG IN ADVANCE OF THE DRYLINE IN CENTRAL/N-CENTRAL TX
DURING THE MID-LATE AFTERNOON. 

EXPERIMENTAL NMM WRF AT 4KM RESOLUTION INDICATES CONVECTIVE
DEVELOPMENT ACROSS THE DISCUSSION AREA BEGINNING NEAR 21Z. STRONG
ZONAL UPPER FLOW ACROSS THE REGION...WITH SFC-6KM SHEAR VALUES IN
EXCESS OF 20 M/S...SUGGESTS SUPERCELL STRUCTURES WILL BE SUPPORTED.
ADDITIONALLY...COLD TEMPERATURES ALOFT AND STEEP MID-LEVEL LAPSE
RATES SUGGEST VERY LARGE HAIL IS POSSIBLE. MOISTURE APPEARS TOO
MARGINAL FOR NUMEROUS TORNADOES... HOWEVER...VERY FAVORABLE
LOW-LEVEL SHEAR PROFILES SHOULD ALLOW FOR AT LEAST A FEW TORNADOES
DESPITE THE LESS THAN OPTIMAL BOUNDARY LAYER MOISTURE. TORNADO
THREAT MAY BE ENHANCED WHERE STORMS INTERACT WITH REMNANT OUTFLOW
BOUNDARY TO THE EAST.

..BANACOS.. 04/25/2005

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

ATTN...WFO...FWD...OUN...EWX...SJT...

33959834 33729639 32869616 31779630 30539738 30739914
31049915 32729845 

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