Warm and humid air in place over much of the Northeast at midweek is contributing to the risk of drenching, gusty and locally severe thunderstorms on Wednesday.
Additional storms that are heavy, gusty and locally severe will continue to push across the Northeast through Wednesday evening.
The storms will bring the potential for sporadic power outages, but travel delays could become widespread.
"The strongest storms could bring wind gusts up to 60 mph and heavy rain that could lead to flooding," said AccuWeather Senior Storm Meteorologist Kate Danna.
Cities that could be affected through Wednesday evening include Harrisburg and Scranton, Pennsylvania; Albany and New York City, New York; Brattleboro, Vermont; Manchester and Keene, New Hampshire; and Portland and Bangor, Maine.
Heavy thunderstorms will survive the trip to the I-95 Northeast corridor Wednesday night but will roll through the northern and western suburbs during the late afternoon and early evening hours.
According to Severe Weather Expert Henry Margusity, "Cities along I-95 in the Northeast that could have some neighborhoods hit by locally damaging winds, urban flooding and frequent lightning strikes during the first part of Wednesday night include Boston, New York City, Philadelphia, Baltimore and Washington, D.C."
An advancing push of cool air over the Midwest will provide the lift needed to get the storms going and move them along.
Dew points, a measure of moisture in the atmosphere, will climb to around 70 for many locations into Wednesday. This will be a noticeable difference from the 50s that were around a few days ago. The high dew point air will help to fuel the intensity of the storms and increase the risk of torrential rainfall.
The threat for strong storms will shift to the southeast for Thursday. Southern Virginia through the Carolinas will be at the greatest risk for thunderstorms capable of producing damaging winds and downpours.
Although the cold front will bring strong storms, it will also usher in another shot of cool and pleasant air for the end of the week and into the weekend across the Great Lakes and Northeast.
Senior Meteorologist Alex Sosnowski contributed content to this story.
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Great Atlantic Coast Blizzard (1899)
(12th-14th) Boston. . . Storm total of 16 in. Winds gusted to 65 mph at Blue Hill Observatory on the 12th and maintained an average of 50 mph through- out the entire day. 24-36 in. reported of snow just north in vicinity of Beverly. THE BOSTON HERALD declared: "Rarely, if ever, has Boston been so completely snowbound (until Feb. 1978...) as it has been by this blizzard." At the end of the storm depth measured 23 in. in Boston... the greatest depth in 98 years of records from 1871-1969.
Ifrane, Morocco (1935)
-11 degrees - coldest ever in Africa.
Lake Placid, NY (1980)
Finally some snow. Just in time for the opening ceremonies at the Olympic town.