YOUNGSTOWN -  Drivers in the Valley may want to leave a little earlier than usual on their Tuesday morning commute.

According to the Stormtracker 21 Forecast, a dense fog advisory has been issued for part of the WFMJ viewing area, including Mahoning and Trumbull Counties.

Visibility can be less than one-quarter of a mile in some spots.

The advisory is in effect until 9 a.m.