[MCD] SWOMCD

[MCD at goshenarc.org]

ACUS11 KWNS 300043
SWOMCD
SPC MCD 300042 
CAZ000-300545-

MESOSCALE DISCUSSION 2588
NWS STORM PREDICTION CENTER NORMAN OK
0642 PM CST WED DEC 29 2004

AREAS AFFECTED...NRN CA MOUNTAINS ABOVE 3500 FT

CONCERNING...HEAVY SNOW 

VALID 300042Z - 300545Z

SNOW EXPECTED TO STEADILY INCREASE THIS EVENING/OVERNIGHT ABOVE 3500
FT -- NAMELY DURING/AFTER 03Z-06Z TIMEFRAME -- FROM THE KLAMATH
MOUNTAINS/CASCADE RANGE INTO THE NRN SIERRAS OF NRN CA. HEAVY
SNOWFALL WITH RATES OF 1.5-2.0 IN/HR...ACCOMPANIED BY STRONG GUSTY
WINDS...WILL BE POSSIBLE OVERNIGHT.

WITHIN ERN PACIFIC UPPER TROUGH...VORTICITY/SPEED MAXIMA AND FRONTAL
BAND EVIDENT IN WV/IR IMAGERY OFF THE NRN CA COAST. WITH EWD
PROGRESSION OF SYSTEM...DYNAMIC FORCING FOR ASCENT COUPLED WITH SWLY
MID LEVEL WINDS OF 50-70 KTS EXPECTED TO SPREAD ACROSS NRN CA.
SUBSEQUENT INCREASE OF HEAVY SNOWFALL EXPECTED THIS
EVENING/OVERNIGHT ACROSS MOUNTAINOUS TERRAIN OF NRN CA...ESPECIALLY
ON SW FACING SLOPES OWING TO STRONG OROGRAPHIC COMPONENT.

FURTHERMORE CONVECTIVE ENHANCEMENT WILL LIKELY CONTRIBUTE TO LOCALLY
HEAVIER SNOW RATES...PER STEEP MID LEVEL LAPSE RATES OF 7.0 C/KM OR
GREATER /E.G. 00Z MFR RAOB/...AND OBSERVED LIGHTNING OFFSHORE/RECENT
ISOLD CG STRIKES OVER THE NRN SACRAMENTO VALLEY. 18Z ETA/21Z RUC
GUIDANCE SUGGESTS SNOW LEVELS WILL REMAIN QUASI-STEADY IN THE
3500-4000 FT RANGE THROUGH 09Z...RELATIVELY HIGHEST OVER THE NRN
SIERRAS.

..GUYER.. 12/30/2004

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

...NOTICE...
SPC WINTER WEATHER MESOSCALE DISCUSSIONS WILL BE ISSUED ON A 
SCHEDULED BASIS...FOUR TIMES A DAY...BETWEEN 00-01 UTC...
06-07 UTC...12-13 UTC...AND 18-19 UTC AS SIGNIFICANT SHORT
RANGE WINTER WEATHER EVENTS UNFOLD.  THIS SCHEDULE WILL BE
USED FROM DECEMBER 1 THROUGH FEBRUARY 28.

ATTN...WFO...REV...MFR...STO...EKA...

41632121 39932044 38551993 38322041 39702154 40252163
40872192 40962226 40822262 40462281 39782256 39682292
39952325 41092368 41452378 41872342 41892236 

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