Intense Heatwave Sets Record-High Temperatures, Sparks Wildfire Concerns in the Western USA

CBS News

On Sunday, more than 30 million residents were put on high alert as an oppressive heat wave settled over the Western United States. Authorities issued warnings and advisories for excessive heat in regions including California, Oregon, Washington, and the desert Southwest. Forecasters cautioned that temperatures would climb to perilous levels, with cities like Phoenix experiencing temperatures well over 100 degrees Fahrenheit, while areas near Seattle approached all-time highs.

Forecasters from the National Weather Service in Phoenix and Tucson projected extreme temperatures that could touch 111 and 108 degrees Fahrenheit respectively on Sunday. These harsh conditions pose significant health hazards, especially for people lacking access to air conditioning or other cooling measures. Cooling was anticipated to begin slowly by Tuesday in those regions.

Parts of the Pacific Northwest endured several days of unprecedented warmth during the weekend.

Seattle's National Weather Service office had warned of sustained high temperatures starting Friday and continuing into the next week. Seattle-Tacoma Airport recorded temperatures that matched all-time highs Friday night, and several nearby locations either matched or exceeded historical records on Friday and Saturday.

Portland issued an extreme heat warning starting Friday, expected to last until Tuesday morning. The local forecast office predicted temperatures would reach into the triple digits with scant relief even after sunset. Preliminary reports indicated that Friday's high reached 102 degrees, breaking a previous record set in 1942.

Multiple heat records tumbled across Oregon and southern Washington, resulting from this persistent heat. During the Hood to Coast relay in Portland, at least one participant, David Loftus, required hospitalization after losing consciousness.

He recovered following overnight medical observation, according to reports.

Sunday saw sizzling temperatures break numerous high-temperature records in northwest Oregon and southwest Washington. Extreme heat warnings and advisories remain in place through Tuesday, August 26th, urging individuals to stay cool, hydrated, and monitor each other for signs of heat stress.

Extreme temperatures affected residents in both northern and southern sections of California, exacerbating wildfire risks. The heat was expected to peak over the weekend, significantly increasing these wildfire threats.

California's National Weather Service office in Los Angeles issued warnings early Sunday about

unbearably high temperatures ranging from 95 to 105 degrees during the day, with minimal cooling at night.

"The risk of dangerous heat-related illnesses is high, especially for vulnerable groups such as young children, the elderly, those without ventilation and people outdoors," read a public advisory released by the Los Angeles office at 3 AM Sunday. People were advised to restrict outdoor activity to morning hours until the extreme temperatures recede.

The combination of scorching heat, low humidity, and dry lightning enhanced the potential for fire outbreaks across Southern California, a region known for its wildfire devastation.

Warnings about critical fire conditions, such as relative humidity dropping to 8-20%, were issued last week, and continue through at least Saturday. There's a possibility of thunderstorms, which could mix wet and dry weather, further elevating fire hazards.

Governor Gavin Newsom had already preemptively mobilized firefighting resources, including crews, engines, water tenders, helicopters, and other equipment distributed across Los Angeles, Kern, Santa Barbara, San Bernardino, and Ventura counties in advance of the heat surge. Further deployments were made to two additional counties over the weekend.

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Emily Mae Czachor reports and edits for CBSNews.com, covering urgent stories, severe weather events, and social justice issues. Her writings also appear in the Los Angeles Times, BuzzFeed, and Newsweek.