Chilly storm may bring high-elevation snow Northwest US this week

The same storm set to return snow to the highest elevations of the northern Rockies will help to disperse smoke in other parts of the northwestern United States into Monday night.

People who have had to limit time outdoors due to hot and smoky conditions much of this summer may welcome the refreshing change.

After spotty showers and chilly highs in the 60s F close out the weekend in Seattle and Portland, Oregon, temperatures will bounce back to more seasonable levels in the 70s F on Monday.

Average daytime temperatures at the end of August range from 80 degrees Fahrenheit in Portland to 75 in Seattle.

The cooler conditions will spill farther east on Monday with highs expected to be held to the 50s across most of Montana, on a day when highs in the lower and middle 80s are more common in the lower elevation cities of Billings, Bozeman and Great Falls.

Temperatures may not even climb out of the 30s and 40s in the high country of Montana and Idaho.

Clouds, rain and gusty winds will create even lower AccuWeather RealFeel® Temperatures.

"Enough chilly air will be present for snow to fall and accumulate several inches in the highest terrain of Montana, Idaho and northwestern Wyoming," according to AccuWeather Senior Meteorologist Kristina Pydynowski. "This includes around Yellowstone National Park."

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Anyone who is hiking or camping in the northern Rockies will need to make sure they are properly prepared for the snow and chilly conditions, as lows will dip into the 20s and 30s on Monday night.

The damp, cooler weather will help to lower the risk of wildfire growth and ignition. Firefighters may gain the upper hand of the many wildfires burning.

"South of where rain is expected to fall from the Sierra Nevada of California to western Wyoming, gusty winds will ramp up the fire danger into Sunday evening," Pydynowski said.

"This threat should shift to Wyoming on Monday," she said.

The wind accompanying the storm should help mix out some of the wildfire smoke early this week, according to AccuWeather Meteorologist and western U.S. blogger Jordan Root.

Light winds and heat have trapped smoke from hundreds of large wildfires near the surface for weeks across western Canada and the U.S.

Early last week, Seattle reported worse air quality than Beijing, according to USA Today.

The smoky conditions caused flight delays and cancellations in Seattle, Salt Lake City and Medford, Oregon, last week, The Oregonian reported.

In the wake of Monday's showers over interior areas, Root expects near- to slightly below-normal temperatures to dominate the rest of the week across the Northwest.

"Tuesday will be the only exception along the I-5 corridor where temperatures may jump above normal in between systems,” Root said.

"No long stretches of heat are expected anytime soon," he added.