U.S. Braces for Extreme Weather, From Southern Heat to Possible Snow in the Rockies

After days of intense flooding in Florida, that state and many others are bracing for an intense heat wave, while the Pacific Northwest will experience unseasonably cold weather and the potential for late-season snow in the Rocky Mountains early next week.

The chaotic weather map includes the potential for severe thunderstorms developing in between the hot and cold fronts. Forecasters said the colliding fronts could lead to areas of flash flooding between eastern Nebraska and northern Wisconsin on Saturday night...