Following taste of fall, temperatures in parts of the West to soar as August winds down

A record run of 100-degree temperatures came to an end in Las Vegas on Friday, but AccuWeather meteorologists warn the heat will return to Sin City and other parts of the West for the new week.

In the wake of the coolest weather since last spring, summertime heat will quickly rebound in parts of the West for the last week of August. AccuWeather meteorologists warn that record high temperatures could be in jeopardy in some areas.

The big jump in temperatures, mainly focused in California and the Southwest, is part of a volatile weather pattern that will continue to bring sharp changes in the weather to the West to close out August.

The changing conditions will also complicate efforts to control wildfires in the region and could spark more, as gusty winds are expected as temperatures change quickly.

A 35-degree temperature swing in some areas

Amid a very hot summer, where temperatures as a whole have run several degrees above the historical average, the cooler weather over the last several days represented a stunning change to the weather not seen in many months.

"An unusually strong storm brought unseasonably cool weather to much of the West Coast late in the week," said AccuWeather Meteorologist Grady Gilman. "Temperatures were 20-25 degrees below historical averages and even set daily record low maximums."

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In Sacramento, California, the mercury failed to get out of the 70s on Friday, marking one of the coolest August days on record. In Las Vegas, a record 64-day run of triple-digit heat came to an end on Friday, when the high temperature was "just" 96 degrees.

Following another day or two of the fall preview, a big change is in store for the region, warns Gilman. "A noticeable warmup will begin by early in the new week and peak midweek as an area of high pressure builds in."

Away from the immediate Pacific coast, temperatures will increase by up to 10 degrees each day from Sunday to Tuesday. By Tuesday, the upper 90s will return to Sacramento, a jump of nearly 25 degrees from Friday.

"Some locales can see an increase in afternoon high temperatures of up to 35 degrees in just a handful of days," said Gilman. "This includes locales around the North Bay of San Francisco, where temperatures struggled to reach the 70s on Friday but can make it into triple-digit territory come Tuesday."

Volatile temperatures mean a higher fire risk

AccuWeather meteorologists also warn that the sudden and uneven changes in temperature across the West (the Northwest and Rockies will seesaw back and forth from warmer and cooler conditions) over the coming week can kick up the wind and prolong a wildfire danger.

While recent rain showers in the region have aided firefighters, dozens of fires are still burning across the region, according to InciWeb.

The fire danger will remain high until the end of the weekend as the storm responsible for bringing the cooler weather as of late moves across the interior West. Another storm arriving in the Northwest in the new week will also bring an uptick in the fire risk there.

In addition, as heat builds in California and the Southwest, mainly dry conditions are expected, which will increase fire dangers to end August. In the Four Corners region, where monsoon thunderstorms will pop up during the week, lightning traveling a great distance from the storms can also spark fires.

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