Locally dense fog possible Wednesday morning

 

UPDATE: A DENSE FOG ADVISORY has been issued for Green, Rock and Walworth counties in southern Wisconsin until 10am Wednesday. 

Skies have been filled with cloud cover Tuesday afternoon as moisture remains in place. Despite the cloud cover temperatures were still able to warm into the low to mid 40s, reaching 44 degrees in Rockford.

A weak upper-level disturbance moving in from the southwest late in the afternoon allowed some light snow showers/flurries and light rain to develop, stretching from northeast Iowa into northwest Illinois and Wisconsin. Not much of that locally has been able to reach the ground due to drier air aloft. Further north there were a few light snow showers that, while not accumulating, did cause roads to become wet throughout the day. As evening temperatures fall through the 30s there may be some slick spots on the roads north of the state line Tuesday night.

There has also been a little clearing in the thicker cloud cover to the west and while our skies won't completely clear overnight, pockets of clear sky are possible. This could lead to areas of fog, some locally dense, through the morning Wednesday. Overnight lows are forecast to fall into the low 30s which means freezing fog is also possible. The fog shouldn't be too widespread but watch for changing visibility and driving conditions across the Stateline during the morning, especially before the sun comes up, and use caution on elevated surfaces as slick spots are possible. Some of our forecast models are suggesting visibility falling to a less than a mile across northern Illinois and south-central Wisconsin.

Skies will then remain mostly cloudy Wednesday afternoon with temperatures warming back into the low to mid 40s. Rain showers still look to move in Thursday afternoon with a mix with, or transition over to, wet snow overnight Thursday into Friday.