Enjoy the last of summer in western Washington as fall weather trickles in

Is summer weather coming to an end? I’ll get to that answer later, yet a change in the recent warm weather is expected to unfold this weekend and into the first half of next week.

An upper-level low well off the coast is forecast to spin clouds, spotty light showers, and cooler temperatures onshore during the weekend. Any rain amounts are anticipated to be limited.

A threat of late-day thunderstorms is possible in the mountains Saturday, mainly in the Cascades. So if there are plans to be in the mountains this weekend, be prepared for the possibility of lightning.

High temperatures in western Washington this weekend are expected to cool into the lower to mid-70s, with 60s along the outer coast. The average early September high temperature in the Puget Sound region is in the mid-70s.

Chance of wet weather next week in western Washington

Heading into the first half of next week, the weather could get wetter. The offshore upper-level is forecast to work its way into western Washington, bringing with it a greater chance of showers. Tuesday looks to be the wettest day. High temperatures will struggle to reach 70 degrees.

By Wednesday, the lowlands of Western Washington could have between a quarter and a half inch of rain. In the mountains, up to an inch of much-needed rain could accumulate.

Any rainfall will be welcome given the ongoing dry conditions. Much of the state is in moderate to extreme drought conditions according to the U.S. Drought Monitor. Seattle is over 6 inches below average for the year thus far, Olympia has a 9 and a half inch rain deficit, and usually wet Forks on the north coast is nearly 23 inches below normal for the year.

Lightning could spark new wildfires

Thanks to the dry conditions, the threat of wildfires remains elevated. The risk of lightning in the mountains this weekend could spark new wildfires.

The expected rainfall by the middle of next week, though, will help dampen those heightened wildfire concerns. The Bear Gulch wildfire in Mason County has been burning for about two months now. The rain will help put some water on this fire, along with the active Wildcat fire east of Mt Rainier that sent its share of smoke over Western Washington since Wednesday.

Smoke from both of these wildfires has helped create poorer air quality across much of western Washington, pushing into the moderate category in many areas. The anticipated rainfall will also help cleanse and improve air quality.

If longer-range weather charts are on track, weather conditions look to dry out again later next week with the sun reemerging. The 8-to-14-day outlook runs into mid-September

shows above-average temperatures. Yet the threat of any 90-degree days is basically over. The odds of temperatures climbing back into the 80s, though, remain possible, but grow smaller as the fall season approaches.

This time of year, each day is losing over three minutes of daylight. Sunsets are now coming before 7:45 p.m. By the time we reach the fall equinox on September 22, the loss of each day’s daylight will be close to three and a half minutes.

At this point, summer is anticipated to return late next week with more seasonable temperatures. So summer weather is not entirely over. Yet, fall is right around the corner. Enjoy the remaining days of summer.

Ted Buehner is the KIRO Newsradio meteorologist. You can read more of Ted’s stories here and follow him on X