NOAA's National Weather Service Weather Forecast Office

First Winter Storm of the Season Hits the Bi-State Area

The first winter storm of the season affected the Mississippi River Valley Region on Tuesday Night and Wednesday, resulting in a band of moderate to heavy snow from east-central Kansas into the southern Great Lakes.  Rain spread across the area on Tuesday as the storm system moved through the Southern Plains.  The rain then changed to snow from northwest to southeast from late Tuesday night into Wednesday, as the storm center moved across the Lower Mississippi River Valley pulling much colder air southeastward.  There were several reports of thunder accompanying the heavy snow in the Kansas City area, and also in the region between Quincy and Springfield, Illinois.

The main impact of the storm system for the Bi-State area began early Wednesday morning when the rain changed to snow around dawn across central and northeast Missouri.  The changeover continued to migrate southeastward as the morning progressed with the transition to snow occurring between 10:00 am and 11:00 am in western portions of the St. Louis Metropolitan Area.  The changeover from rain to snow was also rather abrupt, followed quickly by moderate to heavy snow.  Despite the initially warm ground temperatures in the upper 40s to lower 50s, the intense snowfall rates of 2 to 3 inches per hour resulted in rapid cooling of the ground and quick accumulation of the snowfall.  Area roadways went from wet, to slushy, to snow covered in one hour, resulting in numerous traffic accidents.  Interstate 70 was closed for a period of time between St. Louis and Columbia.  The snow ended over southwest and south central Illinois early Wednesday evening as the storm system exited into the Ohio Valley.

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Total Snowfall Map