CHICAGO — A Winter Weather Advisory is in effect calling for 2 to 6-inches of accumulating wet snow across much of the Chicago area later tonight into Friday morning – with the heaviest snow falling between 3 a.m. and 7 a.m. Friday.

Anticipate a slow and slippery morning commute Friday.

Greatest snowfall of 4 to 6-inches looks to occur along and south of the Interstate-80 corridor. Snowfall totals are expected to decrease as you go north, with 2 to 4-inches likely in the vicinity of the Interstate-88/290 corridor, ending up with an inch or less along the Illinois-Wisconsin state line. The Advisory area is delineated in purple-shading on the headlined map.

Aided by a strong jet stream aloft, a band of accumulating snow is expected to spread rapidly east ahead of low pressure moving east out of the central Rockies today (note the rather narrow band of pink and purple-shaded Winter Warnings/Advisories stretching out to the west and east of our area on the map below). As the precipitation approaches our area from the west this evening, it could start out as a rain/snow mix, changing over to all snow as it spreads over the entire area. Snow should gradually end from the west later Friday morning.

Thursday/Friday Watches/Warnings/Advisories