Torrential rain and locally gusty thunderstorms have convered on the mid-Atlantic on Friday, causing flash, urban and small stream flooding.
The heaviest and most persistent rainfall and greatest risk of flooding Friday evening will shift off the mid-Atlantic coast but will linger over upstate New York and progress slowly across New England.
Heavy rain will retreat to eastern New England by Saturday morning.
A general 1 to 2 inches of rain will fall along the I-95 corridor with higher amounts of up to 4 inches.
Enough rain has fallen in Virginia and Maryland during Thursday to Friday morning to cause small stream flooding and will push a few of the major rivers to major flood levels into the weekend. This includes portions of the Potomac River. Similar problems have been occurring with small streams in portions of upstate New York and Pennsylvania.
Multiple secondary roads have been closed from North Carolina to Virginia, where between 2 and 6 inches of rain fell Thursday into early Friday morning. Some roads have been washed out, and multiple basements have been flooded. Flash flooding forced evacuations in Chapel Hill, North Carolina, and in some of the suburbs around Washington, D.C.
Flash and small stream flooding in central Pennsylvania closed multiple roads.
Portions of upstate New York around the Finger Lakes have been hit with heavy rain, flooding and road closures for the second time this week.
Strong southeasterly winds have caused water to pile up in the northwestern portion of the Chesapeake Bay with flooding reported at Baltimore's Inner Harbor Friday morning.
Major cities that will be impacted by a six- to eight-hour episode of drenching showers and thunderstorms include Atlantic City, New York City, Albany, New York, Hartford, Connecticut, and Boston. While the intense rainfall and poor visibility may last only a few hours, the impact on travel and outdoor activities may linger longer.
Be aware of and avoid flooded areas. Never attempt to cross running or flooded water— DC Police Department (@DCPoliceDept) May 16, 2014
According to Northeast Weather Expert Dave Dombek, "The timing of the rain is such that Washington, D.C., and Baltimore have the greatest impact Friday morning, while around New York City the worst of the rain will be Friday evening."
The heaviest rain is scheduled to swing through Boston Saturday morning and midday.
For fans heading to MLB games Friday, especially in the Northeast, be sure to check with schedule in case of a postponement. Games most likely to be affected by downpours during or just prior to scheduled play are the Reds at Phillies and Pirates at Yankees.
Moisture from the Gulf of Mexico, the Atlantic Ocean and the tropics will continue to be drawn into the system as it moves slowly along into Saturday.
As the system passed through the Central states earlier this week, it caused flash flooding. In addition, the zone of tropical moisture forecast to feed in along the Atlantic coast produced flash flooding and mudslides in Puerto Rico and the Virgin Islands this past weekend.
In the wake of the drenching rain, cooler air will roll eastward from the Midwest in time for the weekend. Similar to a storm that brought cool, unsettled conditions to the area a week ago, this new storm has the potential to bring building clouds and spotty showers mainly during the afternoon and evening hours.
Beneath the storm, high temperatures may be held in the 50s over the mountains and the lower 70s in many areas east of the Appalachians.
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.
Rounds of snow and slippery travel this week around Boston will be followed by the coldest air of the season so far for 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.
Arctic air will blow across the Cleveland area during the second half of the week and into the weekend, making for the longest sustained cold wave that the city has seen since last winter.