A busy stretch of summer weather is unfolding across the U.S., with dangerous thunderstorms, heavy rainfall, flash flooding, and scorching heat all in the mix. Severe storms with damaging winds and large hail are expected across the Central and Northern Plains, while heavy downpours raise flash flood concerns from the Mid-Atlantic to Florida. A tropical disturbance is moving across Florida and into the northern Gulf Coast, adding to the flood threat. Meanwhile, extreme heat builds across the East, and fire danger increases across the Great Basin. Severe thunderstorms are possible from Ontario to the Maritimes; meanwhile, air quality related to wildfire smoke is impacting central and western Canada.