Torrential rainfall Thursday into Friday first drove small streams out of their banks and is now leading to flooding of the Potomac River and others in the mid-Atlantic this weekend.
Multiple roads were closed from North Carolina to upstate New York early Friday as a round of heavy rain moved into the area and stalled.
From 2 to 6 inches of rain fell on part of the Potomac River basin late last week and has been enough to cause the waterway to rise.
National Weather Service hydrologists state that minor to moderate flooding is occurring from Point of Rocks, Maryland, to Washington, D.C.
Moderate flooding of the Potomac River around Washington, D.C., will cause unprotected areas of the Washington Harbour to flood.
Farther south, heavy rain fell across portions of southern Virginia and the Carolinas Wednesday night through Thursday, and streams and rivers swelled out of their banks.
Moderate flooding is occurring along parts of the Meherrin River in southeastern Virginia. The Neuse River at Smithfield, North Carolina, reached moderate flood stage earlier this weekend. The Tar River at Tarboro, North Carolina, is also projected to reach moderate flood stage on Tuesday.
People in unprotected areas along the river will need to relocate. Park land and roadways along the river will take on water, and people should avoid these areas until waters recede in the upcoming few days.
Farther north, less intense, less widespread heavy rain has fallen over much of the Susquehanna River Basin. While a significant rise is forecast along much of both branches of the river this weekend, in most cases waters will stop short of moderate flood levels.
The duration and intensity of the rain did not cause flooding on this level as it moved over New England on Saturday.
Only spotty shower activity is forecast through Tuesday in the wake of the heavy rainfall.
Small streams will recede and runoff from streams feeding into the major rivers will diminish allowing the large waterways to crest.
Cold air and flurries are in store for the New Hampshire primary on Tuesday but should not significantly impact voter turnout.
Snow and slippery travel will arrive in the mid-Atlantic states prior to the middle of the week.
Waves of arctic air invading the eastern half of the United States this week will culminate with the coldest weather of the season so far for some areas by the Valentine's Day weekend.
Chilly air will visit New Orleans this year for the annual Mardi Gras celebrations and linger over the city until later in the week.
Warmer air will build from California to Washington into Tuesday raising temperatures to near-record levels and increasing the risk of wildfires in some areas.
Denver Broncos fans celebrating the Super Bowl win will see ideal conditions for Tuesday's parade and pep rally.