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.

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

Environment Canada has issued both a severe thunderstorm watch and a heat warning for the Montreal Island area, as dangerous heat and unstable weather take hold to start the week. Temperatures will soar to 32°C this afternoon,