A major heat wave settling over the Pacific Northwest will bring several days of potentially record-breaking triple-digit temperatures this week, echoing a deadly heat wave that tormented the region last summer.
Abnormal temperatures on Tuesday stretched from British Columbia to parts of Northern California, according to Richard Otto, a National Weather Service meteorologist who described the heat as “dangerous.” Heat warnings and advisories have been issued for the entire region, covering about 13 million people.
Highs in the 90s early in the week will continue to increase, reaching up to 110 degrees in some parts of Oregon and Washington by the end of the week.
Multnomah County, Ore., and the city of Portland issued emergency declarations for the long stretch of expected high temperatures, and are opening several cooling centers. Seattle also opened centers and put work crews on standby to repair roads and electrical lines that might be damaged by the heat.
Summer temperatures in the Pacific Northwest tend to be in the 70s and 80s, so fewer homes and buildings there are built for very hot weather, compared with other parts of the United States, making heat waves in the region more dangerous and harder to bear. Frequent hot snaps in recent years have led to an increase in the prevalence of air-conditioning, but a large part of the population remains at risk. An extended heat wave last June was blamed for hundreds of deaths across the region.
A big worry for officials is how people without air-conditioning will endure the warm nights. The average low for July in Portland is about 58 degrees, but forecasters say that this week, temperatures in the city may not drop below 70 on some nights. That has only happened six times in the past decade, according to Multnomah County officials, and five of them were last year.
The Pacific Northwest heat wave adds to a summer of misery in much of the United States. The Northeast saw a heat wave last week, and the central part of the country has had nearly two months of searing temperatures.
After a week with highs often approaching 110 degrees, the Southern and Central Plains will finally see some measure of relief on Friday when a cold front moves through, bringing rain and more moderate summer weather.