Steady snowfall throughout the day and through the evening. Slight chance for rain in the evening. The snow should end by late Sunday night.Morning low: 24.
Afternoon high: 32.
Storm total snowfall: 5-7". Heaviest amounts to the north of Fort Wayne; slightly less to the south.
Technical stuff: As of Saturday evening, a light band of snow has developed as a result of warm air advection just ahead of an Alberta clipper system that will be responsible for the first half of the incoming snowstorm. Some isentropic lift and associated moisture advection is ongoing over the as well, which will continue to force snow development tonight. The layer has been easily saturated over the past several hours with surface winds backing to the south already allowing for increasing warm air and moisture advection.
The shortwave that will help produce the second half of the snowfall has barely formed over the Pacific Northwest around 500 hPa and above, but it is more apparent toward 850 hPa. This will become more amplified by Sunday as it passes over the Rockies. As zonal flow continues to develop greater curvature, surface cyclone development over the Plains will be likely. Both 00 UTC NAM and 18 UTC GFS form an elongated area of surface low pressure extending from the Texas Panhandle up to the Great Lakes on Sunday. Cyclonic vorticity advection will develop in areas along the shortwave, most notably to our north where highest snowfall accumulations are expected-- likely in Michigan. Winds will be backing up through 850 hPa which is enough cause for concern for increasing temperatures on Sunday which could lead to some light rain mixing in with the snow for a brief time in the evening. This would normally lead to less and/or wetter snowfall; however, this may be overcome by the fluffy nature of the snow observed earlier today. Regardless, models have been showing a southward trend with respect to the freezing line and critical thicknesses, so while the chance of rain is in the forecast, the greater concern for that will probably be south of Fort Wayne. Winds will not be terribly gusty so blowing or drifting snow should not be a major concern. Snow should end as the low pressure moves more northeast out of the Great Lakes and high pressure forms in the northern Plains.
