Meteorologists warn extreme heat and sudden storms could force cancellations or alter plans for communities nationwide.

Dangerous heat and warnings were plaguing the region, and the National Weather Service on Saturday forecast a number of cities that were expected to hit record highs.

Illinois shattered its annual tornado record by July, while traditional Tornado Alley states see below-average weather.

A sprawling and chaotic weather pattern is sweeping across the United States this week — bringing severe storms and flash flooding to some regions while others bake under an early-season heat wave.