[MCD] SWOMCD

Mon Mar 20 22:56:07 UTC 2006

ACUS11 KWNS 202258
SWOMCD
SPC MCD 202258 
OKZ000-TXZ000-210030-

MESOSCALE DISCUSSION 0335
NWS STORM PREDICTION CENTER NORMAN OK
0458 PM CST MON MAR 20 2006

AREAS AFFECTED...PORTIONS NWRN/CENTRAL OK

CONCERNING...SEVERE THUNDERSTORM POTENTIAL 

VALID 202258Z - 210030Z

ISOLATED SMALL SUPERCELLS MAY CONTINUE TO DEVELOP FOR ANOTHER 1-2
HOURS WITHIN NARROW CORRIDOR ALONG WARM FRONTAL ZONE...FROM
OKFUSKEE/CREEK COUNTIES NWWD TOWARD AREA JUST S OF END.  TSTMS
MOVING THROUGH FRONTAL ZONE MAY BRIEFLY PRODUCE A TORNADO...AS WELL
AS HAIL NEAR SEVERE LEVELS.  WW NOT ANTICIPATED BECAUSE OF
TRANSIENT/MRGL NATURE OF SEVERE THREAT.

SFC MESOANALYSIS SHOWS FRONTAL ZONE FROM NEAR MCINTOSH/PITTSBURG
COUNTY LINE...IN NWRN PORTION WW 104...NWWD ACROSS LOGAN COUNTY THEN
WNWWD ACROSS DEWEY COUNTY.  SMALL SUPERCELL OVER DEWEY COUNTY
ALREADY HAS PRODUCED BRIEF TORNADO.  BACKED SFC WINDS ALONG FRONT
ENLARGE LOW LEVEL HODOGRAPHS IN REGIME OF STRONG AMBIENT/DEEP-LAYER
SHEAR...WITH MODIFIED VWP/PROFILER WINDS YIELDING 0-1 KM SRH 100-200
J/KG.  MODIFIED RUC SOUNDINGS SUGGEST MLCAPES UP TO ABOUT 500 J/KG. 
BUOYANCY IS SUPPORTED BY VERY STEEP LOW-MIDLEVEL LAPSE RATES FROM
COMBINATION OF SFC HEATING AND COLD AIR ALOFT...AND SHOULD DIMINISH
WITHIN NEXT 2 HOURS.

MEANWHILE...CONVECTIVE GUSTS NEAR SEVERE LEVELS WILL REMAIN POSSIBLE
FROM TSTMS MOVING EWD ACROSS S-CENTRAL OK INTO FAVORABLY HEATED AND
WELL MIXED BOUNDARY LAYER...AMIDST STRONG MIDLEVEL FLOW.  SEVERAL
50-55 KT GUSTS ALREADY HAVE BEEN RECORDED IN MESONET STATIONS AND AT
SPS OBSERVING SITE AS CONVECTION PASSED OVHD.  THIS ACTIVITY ALSO
SHOULD WEAKEN WITH LOSS OF SFC HEATING IN INFLOW LAYER...ACROSS SERN
OK.

ACTIVITY IS EXPECTED TO WEAKEN ACROSS REGION WITH INCREASING
CLOUD/CONVECTIVE COVERAGE...AND LOSS OF SFC HEATING BY ABOUT 00Z.

..EDWARDS.. 03/20/2006

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

ATTN...WFO...TSA...FWD...OUN...

35419766 35669828 35879874 36159894 36309795 35879666
35399599 34589616 33999684 33899751 33959789 34369772
34859771 35279773 

WWWW