Winter Weather Advisory issued ahead of wintry weather Wednesday

 

A Winter Weather Advisory has been issued for northern Illinois beginning Wednesday afternoon and lasting through Wednesday evening/Thursday morning, depending on location. For northwest Illinois the advisory will end at 9pm Wednesday. For Winnebago, Boone, Ogle, Lee, McHenry, and DeKalb counties it'll end at 6am Thursday. The advisory was issued due to the threat for some slick and hazardous travel, especially Wednesday evening.

For the rest of Tuesday evening skies will stay cloudy, but dry. Temperatures stayed in the 20s for most of the afternoon, after starting out around 30 degrees at Midnight. A cool north wind helped to keep temperatures on the cooler side throughout most of the day. The day also started with plenty of sunshine, but cloud cover was quick to build back.

Temperatures through the night won't fall much, remaining in the low 20s through Wednesday morning. A weak incoming low-pressure system will push warm air in from the south, but temperatures at the surface will remain below freezing throughout most of the afternoon. It won't be until the evening that the warmer air, and that's primarily aloft, will reach the state line. This will result in more mixed precipitation throughout the late afternoon and evening.

A band of light flurries or light snow showers may develop during the late morning and early afternoon time frame, lifting north into Wisconsin during the afternoon. Some of the snow showers may linger into the afternoon, mixing in with some sleet as the warmer air tries to move in a few thousand feet above the surface. Some minor accumulations of snow and sleet will be possible through sunset.

After that, temperatures will continue to warm aloft which will allow some light freezing rain and drizzle to mix in through the evening, lasting into the early morning hours of Thursday. Any ice accumulations will remain light, but you don't need much to cause headaches and issues on the roads. A glaze up to a tenth of an inch will be possible across most of the viewing area, with a small chance for slightly higher amounts in our far southern counties.

Most of the precipitation will be done Thursday morning but there may be some lingering icy conditions during that time.