Much of U.S. braces for extreme weather, from southern heat wave 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 there is a potential for late-season snow in the Rocky Mountains early next week.The chaotic weather map includes the possibility of severe thunderstorms developing in between hot and cold fronts. Forecasters said the colliding fronts could lead to areas of flash flooding between eastern Nebraska and northern…