(9:00PM – Wednesday, March 19th, 2025) Wednesday night update on a storm system moving through the region, with a deformation axis of precipitation on the backside, bringing a period of snow across portions of Northern and Central Illinois between tonight and Thursday morning.
Timing…
•Tonight – Thursday Morning, March 19-20th.
Location…
•Northern & Central Illinois.
Impacts…
•Snow accumulation ranging from a trace to 1″ will be likely across portions of Northern and Central Illinois. However, a corridor of higher snowfall totals of 1-3″ will be likely roughly on of either side of I-80. Locally higher snowfall amounts of 3-5″ will be possible within this corridor.
•With marginal temperatures during this event… Snowfall will be heavy/wet, compacting/melting will occur during the event and greatest snowfall accumulation will be on colder surfaces.
•Banding will be likely in the snowfall corridor, with periods of moderate to heavy snowfall possible.
•High winds of 35-55MPH will lead to blowing snow and reduced visibility.
Update…
•With this update, little changes were needed, as the going forecast is on track. We have added wording for locally higher higher snowfall totals being possible in the main snowfall corridor.
Discussion…
•As a storm system moves through the region, a deformation axis of precipitation will translate across portions of Northern and Central Illinois. As dynamics take hold and colder air filters in, precipitation will transition from rain to snow tonight across Northern and Central Illinois. A period of snow will be likely across these areas, from transition on into Thursday morning.
Of focus will be a corridor of a couple to a few inches of snowfall accumulation, roughly on either side of I-80. Locally higher snowfall amounts will be possible. Banding and periods of moderate to heavy snowfall will be possible, with the chance of thundersnow as well.
