[MCD] SWOMCD

[MCD at goshenarc.org]

ACUS11 KWNS 201201
SWOMCD
SPC MCD 201201 
MIZ000-WIZ000-MNZ000-201700-

MESOSCALE DISCUSSION 0177
NWS STORM PREDICTION CENTER NORMAN OK
0601 AM CST SUN FEB 20 2005

AREAS AFFECTED...FAR SERN MN...CENTRAL/S-CENTRAL WI...AND
CENTRAL/SRN LOWER MI

CONCERNING...PRECIPITATION TRENDS...WINTER PRECIPITATION 

VALID 201201Z - 201700Z

AXIS OF PREDOMINATELY MODERATE SNOW WILL SHIFT EWD FROM THE UPPER MS
VALLEY INTO THE CENTRAL/SRN GREAT LAKES REGION THROUGH 18Z.
POTENTIAL EXISTS FOR LOCALIZED 1"/HR SNOWFALL RATES IN A 40-50NM
WIDE BAND FROM BETWEEN EAU/LSE TO BETWEEN MKE/SBM TO FNT/ARB
VICINITY THROUGH EARLY AFTERNOON. A CHANGE TO SLEET AND FREEZING
RAIN IS LIKELY ACROSS FAR SRN LOWER MI BEGINNING AROUND 18Z. 

ONGOING WARM-ADVECTION DRIVEN SNOW EVENT CONTINUES TO PROPAGATE
ESEWD ACROSS THE DISCUSSION AREA. FOCUS FOR ISENTROPIC ASCENT IS
JUST NORTH OF QUASI-STATIONARY SURFACE FRONT EXTENDING FROM FAR SWRN
MN ACROSS SRN WI AND NEAR THE BORDER OF MI AND IND/OH. SYNOPTIC
UPPER-LEVEL SPLIT FLOW PATTERN EXISTS...WITH A WEAK SHORTWAVE TROUGH
TRACKING EWD INTO WRN MN AND A FAST MOVING SRN BRANCH SHORTWAVE
MOVING NEWD THROUGH CENTRAL IA. THE SRN STREAM IMPULSE IS ASSOCIATED
WITH ELEVATED CONVECTION/SCATTERED CG LIGHTNING AS OF 1150Z...AND
SHOULD LEAD TO MORE VIGOROUS LARGE-SCALE ASCENT NORTH OF THE FRONTAL
BOUNDARY BY LATE THIS MORNING. A MARKED INCREASE IN UVV AND
PRECIPITATION AMOUNT IS EVIDENT IN RUC/GFS/NAM GUIDANCE ACROSS
SRN/CENTRAL LOWER MI AS THIS FEATURE BECOMES JUXTAPOSED WITH
FAVORABLE ENVIRONMENT FOR ISENTROPIC LIFT BETWEEN 18Z AND 21Z.
STRONG LOW-LEVEL VEERING IS ALREADY EVIDENT IN VAD WIND PROFILES AT
CHICAGO AND INDIANAPOLIS...WITH SLY 0-1KM WINDS AROUND 40KT. 

ENOUGH WARMING OCCURS IN MODEL SOUNDINGS TO BEGIN A TRANSITION TO
SLEET AND FREEZING RAIN ACROSS FAR SRN LOWER MI BETWEEN 18-21Z. TO
THE NORTH...MODERATE TO OCCASIONAL HEAVY SNOW IS POSSIBLE...WITH
FORCING FOR ASCENT FOCUSED ACROSS SRN/CENTRAL LOWER MI BY EARLY
AFTERNOON WITH A GRADUAL LESSENING OF SNOW RATES EXPECTED ACROSS
CENTRAL MN INTO CENTRAL WI.

..BANACOS.. 02/20/2005

...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...DTX...IWX...GRR...GRB...MKX...ARX...MPX...

44278796 43508457 42878258 42578279 41818331 41818493
41988662 43198945 43639109 43809179 44179238 45079274
45459187 44979039 

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