Excessive Heat Warnings and Heat Advisories are widespread across the Plains across the Mississippi Valley and into the Southeast as high temperatures climb into the 90s and 100s.
The heat and humidity also have prompted warnings for the Northwest.
Widespread severe storms that brought damage reports to the Midwest and Great Lakes will move into the Ohio Valley and the Northeast.
The severe weather threat for Thursday. (Fox News)
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Large hail, damaging winds, and tornadoes are possible.
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Upper-level winds will continue spreading smoke from fires in the West and western Canada across the northern U.S., causing hazy conditions and poor air quality.
The national forecast for Thursday, July 29. (Fox News)
After a very strong 8.2 magnitude earthquake struck off the coast of Alaska last night, all advisories have been lifted, and there appears to be no major damage or tsunami threat.