ZCZC SPCSWOMCD ALL
ACUS11 KWNS 250847 
SPC MCD 250847 
WIZ000-ILZ000-IAZ000-251245-

Mesoscale Discussion 0337
NWS Storm Prediction Center Norman OK
0347 AM CDT Sat Mar 25 2023

Areas affected...northern Illinois into southeastern Wisconsin

Concerning...Heavy snow 

Valid 250847Z - 251245Z

SUMMARY...Heavy snow -- falling at rates in excess of 1" per hour --
can be expected from far east-central Iowa northeastward across
southeastern Wisconsin this morning.

DISCUSSION...Latest water vapor imagery indicates a well-defined
mid-level circulation shifting east-northeastward across
northeastern Missouri at this time.  Just to the north of this
feature, a low-level deformation zone -- noted in radar imagery from
eastern Iowa to southern Wisconsin -- is indicated.  Within this
zone, where temperatures are generally in the low 30s, high radar
reflectivity/KDP indicates that heavy snowfall is ongoing.  Recent
reports of snowfall rates around 2 inches per hour have been
received, corroborating the radar depiction.  

Area model forecast soundings indicate a favorably saturated profile
through the primary dendritic growth zone, with this environment
shifting east-northeastward over the next few hours in conjunction
with the forecast track of the mid-level system.  As such, expect
heavy snowfall to continue over the next few hours across
northwestern Illinois, and gradually expanding across most of
southern Wisconsin.  While rates generally in the inch per hour
range are expected, local rates up to 2" per hour may occur locally,
within the heaviest bands.

..Goss/Grams.. 03/25/2023

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...GRB...LOT...MKX...DVN...

LAT...LON   41489064 42019104 44078828 44358682 44128659 43218666
            42698738 41489064 

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