* WHAT. Visibility one quarter mile or less in dense fog. * WHERE. Portions of central, northern, northwest, and western Virginia. * WHEN. Until 8 AM EDT this morning. * IMPACTS. Low visibility could make driving conditions hazardous.

Plan on patchy dense fog this morning west of the Blue Ridge and from the North Carolina foothills into central Virginia where there was rain Tuesday afternoon and evening. The fog will result in visibility less than one-half mile. Expect rapid changes in visibility when travelling this morning. Allow plenty of time to reach your destination, use low-beam headlights, and add extra space in front of your vehicle. A majority of the fog is expected to dissipate by 10AM.