[MCD] SWOMCD

Mon Jun 12 21:20:04 UTC 2006

ACUS11 KWNS 122118
SWOMCD
SPC MCD 122118 
SDZ000-NEZ000-WYZ000-122315-

MESOSCALE DISCUSSION 1158
NWS STORM PREDICTION CENTER NORMAN OK
0418 PM CDT MON JUN 12 2006

AREAS AFFECTED...ERN WY/SWRN SD AND THE WRN NEB PANHANDLE

CONCERNING...SEVERE THUNDERSTORM POTENTIAL 

VALID 122118Z - 122315Z

ISOLATED SVR STORMS CAPABLE OF PRODUCING LARGE HAIL/DMGG WINDS MAY
DEVELOP EAST OF MAIN SFC TROUGH ACROSS ERN WY...AND OVER THE BLACK
HILLS OF SWRN SD IN THE NEXT FEW HRS. RELATIVELY MARGINAL
SHEAR/INSTABILITY SUGGESTS THAT THE SVR THREAT SHOULD NOT BE
ORGANIZED ENOUGH FOR A WW.

LATEST SFC ANALYSIS SHOWS AXIS OF LOW-MID 50S DEWPTS EXTENDING NWWD
FROM THE NEB PANHANDLE NWWD INTO SCENTRAL MT. RECENT FORECAST
SOUNDINGS INDICATE THAT CINH WAS DECREASING RAPIDLY JUST EAST OF A
SFC TROUGH AXIS EXTENDING FROM NEAR CYS TO SHR. INCIPIENT CONVECTION
WILL LIKELY CONTINUE TO INTENSIFY AND MAY BECOME SVR IN THE NEXT 1-2
HRS /BY 22Z/ AS IT MOVES OFF THE HIGHER TERRAIN OF ERN WY. ALSO
MODEST UPSLOPE FLOW AND WEAKENING CINH MAY ALSO SUPPORT ISOLATED
TSTM DEVELOPMENT OVER THE BLACK HILLS. RELATIVELY WEAK MID LEVEL
WINDS /20 KTS/ DUE TO PRESENCE OF UPPER RIDGE AXIS OVER THE AREA
SUGGESTS THAT VERTICAL SHEAR SHOULD MAINLY SUPPORT MULTICELL TSTM
MODE. HOWEVER...MODEST INSTABILITY /MLCAPES FROM 1000-1500 J/KG/
COMBINED WITH STEEP LOW-MID LEVEL LAPSE RATES WILL SUPPORT AT LEAST
ISOLATED DMGG WINDS/LARGE HAIL WITH THE STRONGEST STORMS.

..CROSBIE.. 06/12/2006

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

ATTN...WFO...UNR...CYS...RIW...

42830289 43830307 44580360 44640540 44350679 43910697
42860609 41710512 41180449 41250335 41850290 

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