Heat and Fire Danger Persist Into Late Week in Parts of California and the Northwest

Brian Donegan
Published: August 10, 2018

Hot temperatures have returned and will prevail in parts of California and the Northwest through late week. That's bad news for the firefighters battling the ongoing wildfires in the region.

A strong upper-level ridge of high pressure, or northward bulge in the jet stream, has built over the West once again. That means well above-average temperatures will engulf much of the region through the end of this week.

A large ridge of high pressure in the West will bring scorching temperatures and a critical fire danger through late-week.

Excessive heat warnings and heat advisories have been posted for a large swath of the interior Northwest, as well as in the Los Angeles area.

High temperatures in those areas will rise into the 90s and 100s, making it dangerous to spend prolonged periods of time outdoors. This is generally 10 to 20 degrees warmer than the average highs for early August.

Low temperatures will also be above-average, providing little relief overnight. Several warm daily record lows have also been set over the past few days in southern California, including San Diego.

Current Heat Alerts

Boise, Idaho, set a daily record high of 106 degrees on Thursday, making it the hottest day there since 2015.

Reno, Nevada set a daily record high of 104 degrees Thursday, which also set an all-time record for the number of days temperatures have reached at least 100 degrees in a year, with 17 days so far in 2018.

Other daily record highs that were set Thursday include San Diego (90 degrees), Missoula, Montana (99 degrees, tied), and Spokane, Washington (103 degrees, tied). 

Additional record highs will likely be tied or broken across the interior Northwest on Friday.

Relief from the hot temperatures will spread from the Pacific Northwest into the northern Rockies Friday through this weekend as a cold front moves through.

Forecast Highs

The hot, dry conditions, along with gusty winds at times, will elevate the fire danger through at least Saturday in parts of the West, including California.

Red flag warnings for the enhanced wildfire danger are posted in northern California through Saturday, including the Mendocino Complex and the Carr Fire.

Parts of the interior Northwest also have an enhanced fire danger late this week. Red flag warnings and fire weather watches are posted from parts of Washington and Oregon to Idaho and Montana.

Smoke from the ongoing wildfires in the region will continue to make air quality poor in some areas.

(MORE: Wildfire Smoke Detected in Majority of U.S. States)

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