Excessive Heat Warnings and Heat Advisories are widespread from the Northern Rockies to the Plains and the lower Mississippi River Valley this week as hot and humid conditions build with high temperatures climbing into the 90s and 100s.

       Leftover monsoon moisture and storms will keep the threat for flash flooding across portions of the Southwest into Southern California through at least tonight.

       Heat advisories currently in effect. (Fox News)

       With more than 80 large wildfires burning in the West and western Canada, upper-level winds will continue spreading smoke from the Northwest to the Northeast, causing poor surface air quality.

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       The national forecast for Tuesday, July 27. (Fox News)

       Strong to severe storms that brought damage to the upper Midwest and Great Lakes yesterday will expand into the Northeast today.

       Large hail, damaging winds, heavy rain and an isolated tornado will be possible.