Patchy dense fog will result in reduced visibility below one quarter mile in spots and locally hazardous driving conditions particularly in the higher elevations. Motorists should be prepared for changing visibility and longer travel times.

Traffic cameras across the north-central Maryland continue to show areas of significant reductions in visibility. Although many of the roads show good visibility, expect rapid reductions while traveling especially in valley locations and areas near bodies of water. Will monitor the need for any Dense Fog Advisories this morning. Please maintain a safe distance from the vehicle in front and obey local speed limits.

* WHAT. Flooding caused by excessive rainfall is possible. * WHERE. Portions of Maryland, including the following areas, Central and Eastern Allegany, Eastern Garrett, Extreme Western Allegany, Washington and Western Garrett, Virginia, including the following areas, Albemarle, Augusta, Central Virginia Blue Ridge, Central and Southeast Prince William/Manassas/Manassas Park, Clarke, Culpeper, Eastern Highland, Eastern Loudoun, Fairfax, Frederick VA, Greene, Madison, Nelson, Northern Fauquier, Northern Virginia Blue Ridge, Northwest Prince William, Orange, Page, Rappahannock, Rockingham, Shenandoah, Southern Fauquier, Warren, Western Highland and Western Loudoun, and West Virginia, including the following areas, Berkeley, Eastern Grant, Eastern Mineral, Eastern Pendleton, Hampshire, Hardy, Jefferson, Morgan, Western Grant, Western Mineral and Western Pendleton. * WHEN. From 11 AM EDT this morning through this evening. * IMPACTS. Excessive runoff may result in flooding of rivers, creeks, streams, and other low-lying and flood-prone locations. Creeks and streams may rise out of their banks. Flooding may occur in poor drainage and urban areas. Low-water crossings may be flooded. * ADDITIONAL DETAILS. - Scattered showers and thunderstorms are expected this afternoon and evening. Some thunderstorms will contain heavy rainfall, with rain amounts of 1 to 2 inches in an hour or two. Storms may also train over the same areas causing the possibility of locally higher amounts around 5 inches. - Please visit www.weather.gov/safety/flood for flood safety and preparedness information