Forecasters say some of today's thunderstorms may pack a big punch, with winds strong enough to damage trees and power lines.

Potentially severe thunderstorms are expected to lash the New York City metro area later Thursday, bringing the threat of damaging straight-line wind and hail as we kick off one of the busiest travel weekends of the year.

"At 11:04 a.m., a severe thunderstorm was located over Slocum Creek Campground, or 34 miles northeast of Rome, moving northeast at 20 mph," says the weather service. "Hail damage to vehicles is expected. Expect wind damage to roofs, siding, and trees."