MESOSCALE DISCUSSION 0344
   NWS STORM PREDICTION CENTER NORMAN OK
   0702 AM CDT TUE MAR 31 2009
   
   AREAS AFFECTED...FAR SERN ND...ERN SD AND MUCH OF WEST CENTRAL/
   CENTRAL MN
   
   CONCERNING...HEAVY SNOW 
   
   VALID 311202Z - 311600Z
   
   HEAVY SNOWFALL RATES...1 INCH PER HOUR...ARE EXPECTED TO DEVELOP
   THIS MORNING AND PERSIST THROUGH 18Z ACROSS FAR ERN SD/SERN ND INTO
   MUCH OF WEST CENTRAL MN.  MEANWHILE...MUCH OF ERN SD WILL CONTINUE
   TO EXPERIENCE BLIZZARD CONDITIONS AS NLY WINDS GUST TO 35-40 KT.
   
   FARTHER EAST...A PORTION OF CENTRAL MN FROM THE NRN TWIN CITIES
   METRO WWD INTO MEEKER COUNTY AND NWD THROUGH STC SHOULD CONTINUE A S
   TO N TRANSITION OF SNOW MIXING WITH SLEET AND EVENTUALLY FREEZING
   RAIN TO RAIN. 
   
   11Z SURFACE ANALYSIS INDICATED A 992 MB LOW OVER FAR SERN SD... WITH
   THIS LOW EXPECTED TO TRACK TOWARD SRN MN THIS MORNING AS THE
   ATTENDANT UPPER LEVEL TROUGH/CLOSED LOW BECOME MORE NEGATIVELY
   TILTED APPROACHING THE UPPER MS VALLEY.  THE TRACK OF THE STORM
   SYSTEM SHOULD MAINTAIN A CORRIDOR OF LOW LEVEL CONVERGENCE EXTENDING
   NWD THROUGH WRN MN...AND JUXTAPOSED BENEATH STRONG MID-UPPER LEVEL
   DEFORMATION AXIS.  THIS WILL RESULT IN STRONG DEEP LAYER ASCENT FOR
   DEVELOPMENT OF HEAVY SNOWFALL RATES FROM ERN SD/FAR SERN ND INTO
   WEST CENTRAL MN.  SHORT TERM MODELS INCLUDING 03Z SREF SUGGEST THIS
   AREA SHOULD HAVE THE GREATEST POTENTIAL FOR HEAVY SNOWFALL RATES /1
   INCH PER HOUR/ THROUGH 18Z.  FORECAST SOUNDINGS INDICATED STEEP MID
   LEVEL LAPSE RATES ACROSS THE HEAVY SNOW AREA THIS MORNING...
   SUPPORTING WEAK ELEVATED INSTABILITY FOR ADDITIONAL LIKELIHOOD OF
   SPORADIC LIGHTNING STRIKES.
   
   TO THE EAST OF THE HEAVY SNOWFALL AREA...AND N OF A LINE GENERALLY
   FROM HCD TO NRN TWIN CITIES METRO...AREAS OF SNOW/SLEET SHOULD MIX
   WITH FREEZING RAIN LATER THIS MORNING.  THIS PROCESS IS EXPECTED TO
   OCCUR FROM S TO N AS LOW LEVEL WAA ATOP SUB-FREEZING SURFACE
   TEMPERATURES RESULT IN A LOW LEVEL THERMO-STRATIFICATION SUPPORTIVE
   OF A WINTRY MIX...EVENTUALLY CHANGING TO ALL RAIN.
   
   ..PETERS.. 03/31/2009
   
   
   ATTN...WFO...DLH...MPX...FGF...FSD...ABR...
   
   LAT...LON   44819510 44319607 43879741 43749821 44349837 45439836
               45919776 46549679 46999616 47039530 46959435 46329431
               45979387 45779332 45459319 45199352 45159395 44819510