MESOSCALE DISCUSSION 0254
   NWS STORM PREDICTION CENTER NORMAN OK
   0701 AM CST SUN FEB 17 2008
   
   AREAS AFFECTED...NORTHERN MO/CENTRAL AND EASTERN IA INTO SOUTHWEST
   WI
   
   CONCERNING...HEAVY SNOW 
   
   VALID 171301Z - 171800Z
   
   HEAVY SNOW IS EXPECTED TO STEADILY DEVELOP THROUGH THE MORNING
   ACROSS NORTHERN MO INTO CENTRAL/EASTERN IA AND EVENTUALLY SOUTHWEST
   WI. SNOW RATES WILL LIKELY REACH 1-1.5 IN/HR WITHIN THE HEAVIEST
   BANDS. AS STRONG NORTHERLY WINDS INCREASE...BLIZZARD CONDITIONS WILL
   BECOME LIKELY ACROSS CENTRAL IA BY 18Z.
   
   EARLY MORNING SATELLITE IMAGERY/UPPER AIR DIAGNOSTICS FEATURE
   DEEPENING CYCLONE ADVANCING NORTHEASTWARD ACROSS THE LOWER MO
   VALLEY. LATEST SURFACE ANALYSIS REFLECTS INTENSIFYING 988 MB SURFACE
   LOW ACROSS NORTHEAST MO AS OF 12Z...WITH AN INVERTED TROUGH
   EXTENDING NORTHEASTWARD INTO SOUTHEAST WI...AND A SECONDARY INVERTED
   TROUGH NOTED ACROSS NORTHERN MO/CENTRAL IA COINCIDENT WITH EVOLVING
   DEFORMATION BAND. WHILE FREEZING RAIN HAS BEEN COMMON OVERNIGHT
   ACROSS CENTRAL/EASTERN IA INTO SOUTHWEST WI...SHORT TERM
   DETERMINISTIC/SREF GUIDANCE SUGGEST HEAVY SNOW WILL BECOME
   INCREASINGLY LIKELY THIS MORNING IN THE NORTHWEST QUADRANT OF THE
   DEEPENING CYCLONE...WITH AMPLE 12-HR COOLING NOTED IN UPSTREAM RAOBS
   AT OMAHA/TOPEKA. DEEP LAYER FRONTOGENESIS /800-600 MB/ WILL FAVOR
   HEAVY SNOW AND POTENTIAL FOR ENHANCED SOUTHWEST-NORTHEAST ORIENTED
   BANDS ACROSS CENTRAL/EASTERN IA INTO SOUTHWEST WI BY MID/LATE
   MORNING. WITHIN THIS CORRIDOR...06Z NAM/09Z RUC FORECAST SOUNDINGS
   REFLECT AMPLE OMEGA COINCIDENT WITH A FAVORABLY DEEP DENDRITIC
   GROWTH LAYER...ESPECIALLY REFLECTED IN POINT SOUNDINGS ALONG A
   LWD-DSM-OXV-OTM-ALO-CID-LNR CORRIDOR IN SOUTH CENTRAL/EASTERN IA AND
   SOUTHWEST WI BETWEEN 15Z-18Z. FURTHERMORE...LATEST SHORT TERM RUC
   GUIDANCE SUGGESTS A DRAMATIC INCREASE OF LOW TO MID LEVEL NORTHERLY
   WINDS THROUGH THE MORNING...WITH 850 MB/925 MB WIND SPEEDS REACHING
   45 KT/35 KT RESPECTIVELY ACROSS CENTRAL IA BY 18Z.
   
   ..GUYER.. 02/17/2008
   
   
   ...NOTICE...
   SPC WINTER WEATHER MESOSCALE DISCUSSIONS WILL BE ISSUED ON A
   SCHEDULED BASIS FROM DECEMBER 1 THROUGH FEBRUARY 28...FOUR
   TIMES A DAY...AROUND 00 UTC...06 UTC...12 UTC...AND 18 UTC
   FOR SIGNIFICANT SHORT RANGE WINTER WEATHER EVENTS.
   
   ATTN...WFO...MKX...DVN...ARX...DMX...EAX...OAX...
   
   43798972 43168958 42559030 40799205 39839298 39669465
   40749501 42569322 43599136 43939031