(11:30AM - 11/24/18) A morning update regarding the expected snowstorm across portions of Northern and Central Illinois, from very late tonight/very early Sunday morning on into late Sunday night...
Morning model guidance coming in is trending towards a better consensus on track and the potential for higher snowfall totals with this system. With that said, there will be a swath of accumulating snows across much of Northern and portions of Central Illinois. Within this main axis, a corridor of high snowfall amounts upwards of 9-15" are likely.
Temperatures will likely be falling from the mid-30's down into the upper 20's during this event, meaning this will be a heavy/wet snow, with high water content. Due to this, snow rations will be lower that what's often seen during winter. Even with that, high snowfall totals are expected given the high amount of precipitation expected, which will be 1.50-2.00"+ liquid equivalent in the main swath.
Wind will also be a concern from Sunday afternoon into Sunday night. Winds on the north and northwest side of the storm system will increase, with gusts of 30-45mph likely across portions of Northern and Central Illinois. Winds gusts around 50mph could be possible near Lake Michigan. The combination of the expected high winds and heavy snowfall will likely lead to near blizzard conditions for some areas.
Below is our updated TAM depicting expected snowfall amounts. Further updates on this system are likely through the day and into tonight. *It should be noted that due to mild lake waters, snowfall totals will be lower than depicted for downtown Chicago and areas near Lake Michigan. Map scale prevents this from being shown visually.