Special Weather Statement issued December 28 at 2:08PM CST by NWS Green Bay WI

Widespread areas of fog, some locally dense, are expected to
develop tonight across the region beginning around midnight. With
temperatures fall into the middle to upper 20s across northern and
central WI freezing fog will be possible. Fog may linger through
Sunday morning and into Sunday afternoon, particularly across the
Fox Valley and east-central WI.

Motorists are urged to use caution traveling early Sunday
morning. Prepare for sudden changes in visibility and be aware
that if the road looks wet, it could be icy.