Northwest US Heat Wave to Subside by the Weekend

By Brian Lada, Meteorologist

July 8,2015; 9:10PM,EDT

 

 

The opening days of July have brought record-challenging heat to much of the Pacific Northwest, but that is about to change heading into the weekend.
The weather pattern responsible for the record heat has been set up over the region since June, bringing temperatures as much as 20 degrees above normal.

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There is good news though for people across the region looking for a break in the heat.
The weather pattern responsible for the heat wave is expected to break down during the second half of the week with a disturbance moving overhead to take its place for the weekend.

An influx of moisture will accompany the disturbance moving overhead, bringing some clouds and spotty showers for Thursday and Friday.
This should help to prevent temperatures from reaching record levels like they did earlier in the week.
This flip in the weather pattern is not only good for those looking to escape the heat, but also firefighters battling blazes across the region.
"The approaching cooler weather will be a dual-edged sword for wildfire agencies in the Northwest," said AccuWeather Meteorologist and volunteer firefighter Evan Duffey.
"On one hand, the eventual cooling conditions will lead to less extreme fuel temperatures, and lower chances for heat-related illness. On the other hand, the disturbance responsible for the cooler air will first bring breezy conditions Friday into the weekend, helping to spread any active fire."

Dozens of cities across the Pacific Northwest have set record highs during this heat wave, including Seattle.
According to AccuWeather Meteorologist Edward Vallee, temperatures in Seattle during the first seven days of July have averaged more than 11 degrees above normal.
In this same period was a stretch of four days where Seattle set a new daily high-record temperature.
Medford, Oregon, is another city that has had excessive heat, averaging more than 14 degrees above normal in the first seven days of July with temperatures reaching as high as 108 F.
The hottest air during this heat wave has focused just east of the Cascade Mountains where temperatures topped out in the triple digits on a daily basis.
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"Ongoing El Niño and anomalously warm waters over the Pacific are likely playing a role in how warm the western U.S. has gotten over the last month," said Vallee.
With El Niño showing no signs of letting up in the coming months, it is likely that a weather pattern similar to that of early July will set up over the region once again.