If driving, slow down, use your headlights, and leave plenty ofdistance ahead of you.
* WHAT...Visibility one quarter mile or less in dense fog.* WHERE...In Maryland, Anne Arundel, Central and Southeast Howard,Northwest Howard, Northwest Montgomery, and Southern BaltimoreCounties. In Virginia, Northern Fauquier and Western LoudounCounties.* WHEN...Until 10 AM EDT this morning.* IMPACTS...Low visibility could make driving conditions hazardous.