[MCD] SWOMCD

[MCD at goshenarc.org]

ACUS11 KWNS 202032
SWOMCD
SPC MCD 202031 
MTZ000-WYZ000-202200-

MESOSCALE DISCUSSION 0934
NWS STORM PREDICTION CENTER NORMAN OK
0331 PM CDT FRI MAY 20 2005

AREAS AFFECTED...SWRN/SCENTRAL MT...FAR NWRN/NCENTRAL WY

CONCERNING...SEVERE THUNDERSTORM POTENTIAL 

VALID 202031Z - 202200Z

ISOLATED STORMS MAY BEGIN TO POSE A SVR HAIL THREAT AS THEY DEVELOP
OVER THE HIGHER TERRAIN OF SWRN MT AND FAR NWRN WY IN THE NEXT 1-2
HOURS. A WW IS NOT ANTICIPATED OVER SWRN MT DUE TO MARGINAL
INSTABILITY...BUT ONE MAY BE NEEDED BY 00Z OVER SCENTRAL MT/NCENTRAL
WY AS CONVECTION ENCOUNTERS INCREASING INSTABILITY.

TRENDS IN SFC ANALYSIS SHOW AXIS OF 50+ DEWPTS HAS MOVED AS FAR WWD
AS BOZEMAN AREA IN SWRN MT AS SFC LOW DEEPENS OVER SWRN MT. DESPITE
SUBTLE MID LEVEL SHORTWAVE RIDGE MOVING OVER AREA PRESENTLY
...LARGER SCALE VERTICAL MOTION WILL CONTINUE TO INCREASE  AS STRONG
MID LEVEL SHORTWAVE TROUGH APPROACHES THE REGION. 50-70 KT MID LEVEL
WIND PROFILES WILL SUPPORT CLOUD LAYER SHEAR AROUND 50 KTS...MORE
THAN ADEQUATE FOR STORM ROTATION. INSTABILITY OVER SWRN MT WILL
REMAIN MARGINAL WITH AROUND 500 J/KG OF MLCAPE. HOWEVER...COMBINED
WITH THE STRENGTH OF SHEAR AND STEEP MID LEVEL LAPSE RATES...THERE
WILL BE SOME THREAT FOR LARGE HAIL. THE DAMAGING WIND THREAT WILL BE
MITIGATED INITIALLY BY RELATIVELY LOW DEWPT DEPRESSIONS AND WEAK LOW
LEVEL WINDS.

..CROSBIE.. 05/20/2005

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

ATTN...WFO...BYZ...RIW...TFX...

45910645 46430928 46581085 45861196 45301170 44321033
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