Clear skies, light winds, and moist air will allow fog to develop in most locations early this morning. It should develop first in valleys, but eventually spread over a larger area. The fog is expected to become dense in some areas, with visibility less than a quarter mile. Motorists should exercise caution if traveling through fog, being prepared for quick changes in visibility over short distances. Slow down and use your low beam headlights when you encounter fog, and leave plenty of distance between vehicles.

* WHAT. Visibility one quarter mile or less in dense fog. * WHERE. Portions of east central, northeast, south central, and southeast Kentucky. * WHEN. Until 10 AM EDT Thursday. * IMPACTS. Low visibility could make driving conditions hazardous.

* WHAT. Visibility of a quarter of a mile or less in dense fog. * WHERE. Garrard, Madison, Adair, Casey, Clinton, Cumberland, Lincoln, Monroe, and Russell Counties. * WHEN. From 4 AM EDT /3 AM CDT/ to 10 AM EDT /9 AM CDT/ Thursday. * IMPACTS. Low visibility could make driving conditions hazardous. * ADDITIONAL DETAILS. The lowest visibilities would be expected in river valleys and other low-lying areas.

The combination of clear skies, calm winds, and wet ground will favor fog formation overnight. It is possible that some areas experience locally dense fog, reducing local visibilities down to a quarter mile at times. Motorists should exercise caution if driving through fog and be prepared for quick changes in visibility over short distances. Slow down, increase following distance, and use low beam headlights in foggy areas.

The combination of clear skies, calm winds, and wet ground from recent rainfall will favor fog formation tonight. It is likely that some areas experience locally dense fog, reducing local visibilities down to a quarter mile at times. Best chances of locally dense fog appear to focus along south central kentucky and the Bluegrass. Motorists should exercise caution if driving through fog and be prepared for quick changes in visibility over short distances. Slow down, increase following distance, and use low beam headlights in foggy areas.