Significant Weather Advisory for Patchy Dense Fog across north central Alabama, northeast Alabama, northwest Alabama and southern middle Tennessee... Patchy Dense Fog has developed across portions of north central Alabama, northeast Alabama, northwest Alabama and southern middle Tennessee, with visibilities dropping to 1/4 mile or less in isolated areas. Motorists are urged to drive with extreme caution, as visibilities will vary significantly given the patchy nature of the fog. Use low beams, reduce driving speed, and allow for plenty of room between you and other cars. The fog should begin to burn off by 8 AM. Stay tuned to NOAA Weather Radio, or a favorite local media outlet, for further statements or updates from the National Weather Service in Huntsville.