(10:15PM - Wednesday 3/9/22) A lead wave and main storm system are expected to impact the region and state, Thursday through Friday. During this period, a swath of accumulating snow is expected across the region and state.
Most model guidance is now in agreement regarding all aspects of this period of potential. With that said, the previous forecast is on track with little to no change needed with this update.
An initial lead wave is expected to move from the Plains Thursday morning, through the Ohio Valley Thursday night, and then into the Great Lakes Friday morning as it weakens. A round of snow will move through the region and across the state with this lead wave, Thursday morning though Friday morning. Furthermore, a main storm system will develop across the Southern Mississippi Valley on Friday, and will then track into the Mid-Atlantic by Saturday morning. This storm system will bring a renewed push of snow across the region and state, Friday morning through Friday night.
Thursday Morning - Friday Morning, March 10-11th ~ Lead Wave Event:
An lead wave is expected to move from the Plains Thursday morning, through the Ohio Valley Thursday night, and then into the Great Lakes Friday morning as it weakens. This lead wave will be accompanied by an area of snow traveling along with it, affecting the region and portions of the state. Snow will first enter the state and move into portions of Western Illinois by mid to late Thursday morning. Snow will then spread across a large portion of Northern and Central Illinois, from Thursday afternoon through Thursday night, before ending Friday morning. Snow will vary in intensity during this period, with snowfall rates of 0.5"+ an hour at times.
Friday Morning - Friday Night, March 11th ~ Main Storm System Event:
As the main storm system moves through the region, an associated renewed push of snow will develop and move across the region and portions of the state, Friday morning through Friday night. This renewed push of snow will spread into portions of Central and Southern Illinois Friday morning, continuing into Friday evening, before ending Friday night. Snow will vary in intensity during this time, with snowfall rates of 0.5"+ an hour possible at times.
Below is the snowfall forecast for this two part event.
-Widespread snow accumulation of 1-3" across a large portion of the state, with locally higher amounts possible in some areas.
-Some travel impacts are possible across much of the state.