Travel woes are likely for Fourth of July revelers with planned trips starting Thursday due to stormy weather.

Thirty-nine million people from Philadelphia to Maine in the Northeast corridor are at risk for severe weather as severe storms are forecast today.

The storms may bring wind gusts up to 60 mph and large hail up to one inch across. This turbulent weather is expected to form after lunchtime on Thursday, lasting until the evening and possibly continuing overnight.

According to the National Weather Service’s Storm Prediction Center, there is a slight risk of severe thunderstorms in parts of the Northern Plains, Northeast, and Mid-Atlantic on Thursday.

New York City will see scattered storms from 2 p.m. to 10 p.m. ET, Philadelphia from 4 p.m. to 11 p.m., and Boston from 3 p.m. to 9 p.m.

In New York, the likeliest window for severe threat will be during prime travel time after work, from about 4 p.m. to 9 p.m., NBC New York reported.

On Independence Day, the West Coast will have a mild and sunny day. Texas and Florida can expect more scattered storms, with the possibility of severe storms in the Northern Plains. The Northeast is set to enjoy pleasant weather, with highs reaching the 80s.

Officials say this is the busiest Fourth of July travel week in years.

The Transportation Security ministration said it expects more than 18.5 million people to travel by air over the holiday week and pass through the nation’s airport security checkpoints.

The Federal Aviation ministration said this Fourth of July travel week will be the busiest seen in 15 years, with over 300,000 flights scheduled throughout the week.

A record 72.2 million Americans are expected to travel domestically this week from June 28 to July 6, according to the American Automobile Association — that’s an increase of 1.7 million travelers compared to last year.

Of those travelers, AAA projects 61.6 million people will travel by car, 5.84 million by air, and 4.78 million by bus, train, or cruise.