Peoria, Ill. (WMBD) – With the exception of the past few days it has been a warm December for Central Illinois. In fact the average temperature was 5.5° above average through the first seven days of the month. The weather pattern will remain active through the end of the week resulting in more large temperatures swings and additional rounds of rain and wind.
The first wave will pass through Illinois on Thursday. While most areas will remain dry, this wave may produce some spotty rain showers before noon. For areas north of I-80, a period of light freezing rain or sleet will be possible before 9 am, but impacts should be limited. A warm front will lift north across the state allowing areas along and south of I-74 to reach the lower 50s in the afternoon.
A stronger storm system will move out of the Central Plains and into the Midwest bringing rain showers and thunderstorms to Central Illinois with heavy snow to parts of the upper Midwest. Light rain showers will lift across Central Illinois in the afternoon with thunderstorms becoming possible in the evening, particularly east of the Illinois River. Rainfall amounts will generally be a quarter of an inch or less.
The greatest risk for severe weather remains south of our area, mainly along and south of I-72. The Storm Prediction Center has issued a Level 2 “Slight Risk’ for southern Illinois while a Level 1 “Marginal Risk” was in place along and south of a Danville to Litchfield line. While this area may shift north in future updates, I don’t expect it to impact our viewing area.
On the cold side of the storm moderate to heavy snow is expected to fall from Wyoming to Wisconsin. Snow accumulations of 4-8 inches are expected in Green Bay, Minneapolis, and Sioux Falls while a narrow band of 8 or more inches is likely from southeast Minnesota to northeast Wisconsin. There’s a limited opportunity for a period of light snow in Central Illinois late Friday night, but no accumulation is expected.