A wide and lengthy plume of tropical moisture climbs northwards along the Appalachian Mountains from the Gulf of Mexico, bringing with it soaking rains for the next few days.
The National Weather Service extended flash flood watches for northern Virginia, portions of Maryland, and the District through Wednesday evening.
A coastal flood watch is in effect from Wednesday evening through Friday morning for D.C.; Harford, southern Baltimore, Prince George's, Anne Arundel, Charles, St. Mary's and Calvert in Maryland; and Prince William County, Manassas Park, Manassas, Fairfax, Arlington, Falls Church, Alexandria, Stafford and King George due to high tides 2-3 feet above normal.
The remnants of Tropical Storm Lee bring heightened flood watches and safety measures along the Potomac River. The National Weather Service said Tuesday that major flooding is possible along the river Wednesday night through Saturday morning at Williamsport and Point of Rocks, and at Paw Paw and Harpers Ferry, W.Va. Moderate flooding is possible near Hancock and Little Falls. Minor to moderate flooding is forecast on many Potomac River tributaries.
Flood watches were also issued in Virginia for the Shenandoah River at Millville in Clarke and Jefferson counties and the Rappahannock River at Remington in Fauquier and Culpeper counties, as well as the Antietam Creek near Sharpsburg in Washington County and the Monocacy River near Frederick in Frederick County in Maryland. Those watches are based on future rainfall predictions.
The Chesapeake and Ohio Canal National Historical Park says it's preparing to close visitor centers and move historic artifacts to upper floors, the Associated Press reported.
Tropical Storm Lee's remnants were responsible for heavy downpours overnight Monday and the showers that will continue to douse us. West of Fredericksburg residents already saw 2 to 4 inches fall before Tuesday morning. Before the storm moves on, as much as 6 inches of rain could fall around the metro area.
Flooding has already been reported on roadways around D.C. News4's Tom Kierein reminds drivers the old safety adage, "Turn around, don't drown." Some National Guard soldiers in New Jersey could have used that advice after they drove their personnel carriers into floodwaters and required rescue, a mistake all caught on YouTube.
Meanwhile, Hurricane Katia remained over the Atlantic Tuesday and appeared to be headed northeast, Chief Meteorologist Doug Kammerer reported. It was downgraded to a strong category 3, with winds of 115 mph, and then a category 2 with winds of 105 mph by Tuesday evening. It's not expected to make landfall but could cause rip currents along the coast.
The wet weather could remain in the area into Friday, but the weekend should be dry -- maybe a 20 percent chance of rain Saturday, Doug Kammerer said.
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