Heat burst in Bradford, PA, last night

Heat bursts are more common in the Plains than here in the East, but we had a small one last night in Bradford, Pennsylvania. The winds suddenly gusted from nearly calm to 21 mph, and the temperature rose more than 5 degrees in one minute.

This website explains how heat bursts form -- essentially evaporating water in a dying thunderstorm causes the air to heat, and that heated air rushes down, hits the ground and spreads out.

Here's a radar loop showing the collapsing thunderstorms just to the west of Bradford before the event occurred: