The greatest concentration of the storms will extend from western and central North Carolina to upstate New York and southwestern New England. This is the same system that produced more than 50 reports of severe weather over the Midwest on Wednesday.
The main impact from the storms in the East is likely to be disruptions to daily activities and travel. An umbrella and pair of waterproof shoes will be a necessity for pedestrians and commuters.
While widespread severe weather is not anticipated, a large number of the storms will bring downpours and gusty winds.
The MLB games scheduled in the afternoon at Philadelphia and the early evening at Baltimore and the Bronx may be delayed for a time.
Enough rain may fall to briefly flood poor drainage areas along streets and highways. The downpours will also restrict visibility for motorists and raise the risk of some vehicle hydroplaning. Motorists are encouraged to be patient, slow down and allow extra time for their commutes.
Brief airline delays are likely as the storms approach and pass over the major hubs in Pittsburgh, Philadelphia, Baltimore, Washington, D.C., New York City and Newark, New Jersey. Expect delays at the dozen or so secondary airports in the region.
A small number of communities may be hit by marble-sized hail and strong wind gusts that may break tree limbs. Isolated power outages can occur as a result.
The greatest threat for people outdoors will be from lightning strikes.
Be sure to move indoors at the first clap of thunder. Open porches, picnic pavilions and golf carts do not offer adequate protection from lightning.
Never stand under a tree or a small group of trees for protection from the storm as lightning often strikes the highest object in the area and can travel several yards through the ground.
Much of the region can expect dry weather on Friday, ahead of unsettled conditions that will advance slowly from north to south over the Mother's Day weekend. The rain may threaten outdoor graduation and wedding plans.
EDITOR’S NOTE: Alex Sosnowski is a senior meteorologist for AccuWeather.com.