Updated

Hot temperatures will build over much of the country this week.  

Excessive Heat Watches are in effect across northern California and the Pacific Northwest, including Seattle and Portland, which won’t help firefighters battling nearly 100 large fires in the West.   

Heat Warnings and Advisories are also in effect for the Plains to the Mississippi River Valley, where hot and humid conditions continue most of the week.   

Heat advisories currently in effect across the U.S.

Heat advisories currently in effect across the U.S. (Fox News)

US SWELTERS AS HEAT WAVE SETTLES IN 

The Mid-Atlantic and Northeast will also see hot and humid weather mid-to-late week. 

Severe weather struck the Midwest yesterday with several reports of tornadoes, generating damage for the Chicago area up into Wisconsin and North Dakota.   

More strong to severe storms will be possible in some of the same areas today. 

The severe weather threat for Tuesday.

The severe weather threat for Tuesday. (Fox News)

We’re watching a couple of disturbances in the Atlantic for potential development this week as they approach the Lesser Antilles.   

The disturbance closest to the Lesser Antilles is looking more organized today and could become a tropical storm at any time.   

Its path could take it over Puerto Rico and Hispaniola, which would limit development and make for primarily a rain and flood threat.   

Ongoing weather activity in the Atlantic. 

Ongoing weather activity in the Atlantic.  (Fox News)

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In the East Pacific, Tropical Storm Kevin will stay well offshore from southwestern Mexico. 

Behind Kevin, another system will likely become a tropical storm in a few days.