Cool, damp weather to plague Pacific Northwest through late week

By Kyle Elliott, AccuWeather meteorologist

After generally dry and comfortable weather graced residents in the Pacific Northwest early this week, a slow-moving storm system will bring about a change in the weather pattern through Friday.

Damp, unseasonably cool and even severe weather will replace the pleasant conditions throughout the remainder of the traditional workweek.

Warmth from Wednesday east of the Washington and Oregon Cascades will fade as cooler air spills in on Thursday and Friday.

Showers and gusty thunderstorms across the northern Rockies and interior Northwest on Wednesday marked the leading edge of the cooler air, which will hold firm through the end of the week.

On Thursday, the risk of severe thunderstorms will continue well inland.

"Storms over much of Montana and neighboring areas of North Dakota, Saskatchewan and Alberta could be rather violent with the risk of a few tornadoes during Thursday afternoon and night," AccuWeather Senior Meteorologist Alex Sosnowski said.

To the west of the Cascades, raw and chilly weather is on tap along the Interstate-5 corridor from Seattle to Portland, Oregon.

High temperatures will average a few to as much as 10 degrees Fahrenheit below normal in most areas through Friday.

After highs reached the 70s in Seattle and Portland early this week, they will struggle to get out of the upper 60s in Seattle and reach the 70-degree mark in Portland through Friday.

Similar conditions are expected in Spokane and Boise, Idaho, where highs in the 70s and 80s early this week, respectively, will be replaced with highs in the 60s and 70s.

The clouds and showers accompanying the May-like chill will prevent the strong June sunshine from alleviating any of the cool feel to the outdoor air.

Although it will not rain in any one location the entire day, frequent rounds of showers will make it a necessity for residents to grab the umbrella, rain gear and sweatshirt before heading out the door.

Outdoor sporting events could be delayed or, at the very least, disrupted by the wet weather, but the rainfall will be largely beneficial for the Northwest.

Related: 
More severe weather to rattle, drench central US on a daily basis this week 
Northwest Regional Weather Radar 
Detailed Seattle, Washington, weather forecast

The most recent United States Drought Monitor from June 20 shows that moderate to severe drought has developed from Seattle to Portland and across all of northwestern Oregon and western and northern Washington.

Any rain will help give residents a break from needing to water their gardens and give a small boost to streams and creeks that are running low.

The storm system will finally pull northeastward into Canada by the weekend, allowing more sunshine and seasonably warm air to make a comeback and stick around into early next week.

Download the free AccuWeather app to find out how cool it will be in your location this week. Keep checking back for updates on AccuWeather.com and stay tuned to the AccuWeather Network on DirecTV, Frontier and Verizon Fios.