[MCD] SWOMCD

[MCD at goshenarc.org]

ACUS11 KWNS 200703
SWOMCD
SPC MCD 200702 
MIZ000-WIZ000-MNZ000-201130-

MESOSCALE DISCUSSION 2548
NWS STORM PREDICTION CENTER NORMAN OK
0102 AM CST MON DEC 20 2004

AREAS AFFECTED...NERN MN...NRN WI...WRN U.P. OF MI

CONCERNING...HEAVY SNOW 

VALID 200702Z - 201130Z

MDT TO HVY SNOW SHOULD CONTINUE TO SPREAD EWD FROM THE ARROWHEAD OF
MN ACROSS THE WRN PARTS OF LS...NRN WI...AND THE WRN U.P. OF MI
THROUGH DAYBREAK. SNOWFALL RATES AROUND 1 INCH PER HOUR WILL BE
POSSIBLE ACROSS THESE AREAS FOR UP TO A 3-4 HOUR PERIOD.

DEEP SURFACE LOW CENTERED OVER SRN MANITOBA WILL CONTINUE TO
INTENSIFY TODAY AS A STRONG MID LEVEL IMPULSE TRANSLATES ESE ACROSS
THE NRN ROCKIES AND NRN PLAINS. IN RESPONSE TO THIS LARGE SCALE
FORCING...STRONG LOW LEVEL JET AND INTENSE LOW THROUGH MID LEVEL
WARM AIR ADVECTION HAVE DEVELOPED RAPIDLY ACROSS THE DAKOTAS AND THE
UPPER MS VALLEY EARLY TODAY. ETA AND SREF GUIDANCE HAS CAPTURED THIS
PROCESS QUITE WELL AND SUGGEST THAT STRONGEST ISENTROPIC UPGLIDE
WILL REMAIN PROGRESSIVE AND MOVE EWD FROM THE MN ARROWHEAD OVER THE
NEXT 6 HOURS. DESPITE RELATIVELY LIMITED DEEP MOISTURE WITH
SOUNDINGS INDICATING DRIER AIR ALOFT...STRONG FORCING AND VERY COLD
SURFACE-BASED AIRMASS WILL RESULT IN MDT TO HEAVY SNOWFALL RATES
WITHIN THE WARM AIR ADVECTION BAND AS IT MOVES EAST.
FURTHERMORE...LIQUID TO SNOW RATIOS GREATER THAN 10 TO 1 SHOULD
RESULT IN A RELATIVELY BRIEF BUT INTENSE PERIOD OF HEAVY SNOW.

PRECIPITATION SHIELD APPEARS TO BE OUTRUNNING LOW LEVEL WARM NOSE
AND THIS SHOULD LIMIT THE THREAT OF MIXED PRECIPITATION/FREEZING
RAIN.

..CARBIN.. 12/20/2004

...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...MQT...GRB...DLH...MPX...

48489171 48169041 47888908 47578840 46468739 45788764
45728826 45578921 45509027 45509082 45769217 46209271
47169296 47959299 48219307 48509270 

WWWW