SPC MESOSCALE DISCUSSION 2286 FOR SRN/SERN SD...NRN NE...NWRN
IA...SWRN MN CONCERNING...HEAVY SNOW AND NEAR BLIZZARD
CONDITIONS...

VALID 261041Z - 261630Z

1-2 IN/HR SNOWFALL RATES SHOULD BE EXPECTED TO GRADUALLY EXPAND
FROM NRN/NCNTRL NE...ENEWD INTO SRN/SERN SD AND EVENTUALLY INTO
NWRN IA/SWRN MN.

LOCAL RADARS REVEAL MOST INTENSE SNOWFALL PRESENTLY IN CHERRY
COUNTY NEB AND IS GRADUALLY INCREASING EWD INTO
BLAINE...BROWN...AND KEYA PAHA COUNTIES TO THE WNW OF AREA OF
LARGEST PRESSURE FALLS. WV/IR IMAGERY INDICATES CNTR OF MID-LEVEL
CYCLONE IN PLATTE RIVER VALLEY REGION OF SWRN/WCNTRL NEB AS
ENHANCED FORCING IN LEFT EXIT REGION OF UPPER JET IS RESULTING IN
INCREASING PRESSURE FALLS IN MUCH OF ERN NEB. VEERING WIND PROFILE
WITH HEIGHT DISCERNABLE FROM OMAHA VWP REVEALING EXTENT OF WAA WITH
OVER 50 KT SLY FLOW IN THE 3-4 KM LAYER. 

A FOCUSED REGION OF MESOSCALE LIFT JUST WEST OF 850MB LLJ AXIS IS
EXPECTED TO CONTINUE TO DRIVE AREA OF HEAVY SNOWS ENEWD IN TIME
THIS MRNG. IN ADDITION...FRONTOGENETICAL FORCING WILL CONTINUE TO
INCREASE DUE TO PRESSURE FALL REGION IN ERN NEB. THESE INGREDIENTS
ALONG WITH LARGER SCALE PROCESSES...STRONG UPPER-LEVEL DIFLUENCE
JUST AHEAD OF MID-LEVEL CYCLONE...WILL COMBINE TO INCREASE SNOWFALL
RATES GRADUALLY ENEWD INTO SRN/SERN SD THIS MRNG. MAGNITUDE OF WAA
CAN BE NOTED BY RECENT LIGHTING STRIKES IN SERN NEB...AND WITH
STEEP MID-LEVEL LAPSE RATES IN REGION...CONVECTIVE SNOWFALL COULD
ALSO PLAY A ROLE IN FURTHER ENHANCING HEAVY SNOWFALL RATES.    

..NADEN.. 11/26/01