Strong-to-severe thunderstorms are expected over the northern and central Plains, Midwest, Northeast and mid-Atlantic.

VERMONT OFFICIALS URGE FARMERS TO DOCUMENT, REPORT FLOOD-RELATED CROP DAMAGE

Large hail, damaging winds, isolated tornadoes and heavy rain could lead to flash flooding.

Air quality alerts continue for parts of the Midwest and Great Lakes as smoke from wildfires drifts southward from Canada.

The extreme heat will expand toward the North and across the Mississippi Valley, into the Northeast on Thursday and Friday.