Very warm air will build across the northern Rockies while spotty monsoon thunderstorms could spark new wildfires into the weekend.
The upper-level high pressure system responsible for the extreme heat across Texas will shift into the Four Corners region by late week and warm the Rockies.
According to AccuWeather Meteorologist Evan Duffey, "Warm air aloft combined with a good deal of sunshine should bring temperatures to near-record values."
"This period of enhanced heat will bring about conditions that will be uncomfortable for many, and dangerous to some, especially the young and the elderly," he added.
Locations that could challenge record-high temperatures into the weekend include Boise, Idaho; Spokane, Washington; and Great Falls, Montana.
Daytime high temperatures across much of the northern Rockies will range from the middle to upper 90s with localized areas reaching triple digits.
Those with outdoor activities this week should drink plenty of water and wear light-colored clothing to reflect the sunlight off your body and keep your body temperature lower.
This warmth will also build into the northern Plains.
A nearly stationary upper-level low pressure system just off the West Coast will prevent the worst of the heat from building from western Washington to northwestern California.
Monsoonal moisture present across the Rockies could lead to daily shower or thunderstorm development into the weekend.
According to AccuWeather Senior Meteorologist Krissy Pydynowski, "If the monsoon moisture is not rich enough, thunderstorms that erupt will struggle to produce rainfall, but not lightning."
This could lead to areas of dry lightning, which could easily spark new wildfires.
According to the National Interagency Fire Center, there are currently 38 large wildfires across the West burning over 311,000 acres. Of the 38 wildfires, 14 of those are occurring across California. Oregon has the second-most wildfires per state across the West with seven.
During the period from Jan. 1 to Aug. 10, there have been more wildfires this year since 2012 and have burned the second-most acres since 2005 (the most being 2011).
By late week, the stalled upper-level low off the West Coast will push onshore into the Pacific Northwest and across the northern Rockies over the weekend. Much-cooler air will build in behind this storm system.
"The cold front coming on Friday will bring a cooldown across the region, but also provide an increase in winds that could spread wildfires caused by isolated thunderstorms prior to the front's passage," Duffey said.