Storm to Impact Stateline, Much of Midwest

• Snowfall beginning today across northern and central IL, gradually picking up in intensity later tonight.
• The heaviest snowfall will fall late Tuesday morning through Tuesday evening, having major impacts on the evening commute.  Snowfall rates will be heavy, at times in Chicago topping two inches per hour because of lake enhancement, causing difficulty for plows to keep up.
• Some freezing rain can be expected from St. Louis to Champaign, with major icing from Mount Vernon through Indianapolis through Dayton, OH.
• Snowfall totals through daybreak Tuesday of 2 to 5 inches in IL are expected, followed by 9 to 15 inches of snow from late Tuesday morning through Wednesday morning.  Grand totals of 12 to just over 20 inches are expected, making this a top ten storm for most areas.
• Where the highest totals will fall still has uncertainity, but is most likely to be from Quincy, through Peoria, Mendota, and into Chicago.
• Winds will continue to increase through this event, causing blowing and drifting snow in open areas by later Tuesday and persisting all the way through Wednesday, which will continue to cause issues after the falling snow ceases on Wednesday.  Wind gusts of 40 mph are expected because of the system's strength.
• Travel will be guaranteed difficult, if not impossible especially in rural areas.  I would not be surprised to see some interstate closures late Tuesday night into early Wednesday.
• Watches are in effect, and I guarantee these will be converted into warnings later today.

 

Why is this System so Big?

 

    This system has a lot going for it.  It is what weather folks call a classic "panhandle hooker" storm, which is a low pressure developing over the TX/OK panhandles and hooks northeast, dragging rich Gulf of Mexico moisture northward with it.  The low pressure area will be deepening as it tracks northeast because of the jet stream pattern.  The deepening will cause strong winds, as well as heavy snowfall bands.  To the southwest and south of Lake Michigan, moisture and energy coming off the lake will make lake enhanced bands, including over downtown and the south side of Chicago, which could see some of the localized highest amounts.  This storm will have huge impacts over thousands of square miles, with snow, ice, and even severe weather and some tornadoes in the deep South.