(11:45AM - 4/19/21) A storm system is expected to move through the region on Tuesday, bringing a late season snowfall to the heart of the state.
A storm system will eject out from the Plains tonight, then moving northeastward through the Mid-Mississippi Valley and Ohio Valley on Tuesday, and then into the Eastern Great Lakes by Wednesday morning. Model guidance has generally favored a southerly track for this event the past few days. There were a few northern outlier models within guidance, but they have caved to the southern solution. With this update, slight adjustments were made to the location of the snowfall axis, but no significant changes were needed.
An area of snow will spread across a large portion of the state, early Tuesday morning through Tuesday early night. Snow will be of varying intensity during this time, though generally being light to moderate, possibly even mixing with a bit of rain when veyr light. Given it is mid-late April (Mild ground temps and sun angle of issue) and air temperatures will be marginal, greatest snowfall impacts and accumulations will be on colder surfaces, such as grass.
Snowfall totals of 1-3" are across Central Illinois, with amounts tapering north and south of this main axis.
Below is the snow forecast for this event.