Seattle weather forecast: More sunshine ahead but temps begin to cool

Like a fireworks show drawing the curtain on a celebratory night, plentiful thunder and lightning across Western Washington on Monday evening seemingly marked the end of an extraordinary day.

Why was Monday extraordinary, you ask?

It marked the end of a stretch that tied Seattle’s record of four consecutive 80-degree days in May. Seattle also set a record daily high for the fourth day in a row on Monday.

So, with Monday marking the final day in an extraordinary stretch of August-like conditions, let’s take a look ahead at what Mother Nature has in store for Western Washington as we roll out of this record-setting heat wave.

The marine layer responsible for comfortably cool overnight temperatures was expected to retreat to the coast Tuesday. At the same time, the weather system responsible for Monday’s thunder and lightning has shifted off to the east as it weakens, said Dana Felton, a meteorologist with the weather service in Seattle.

Between 1 p.m. Monday and 2 a.m. Tuesday, there were about 1,300 lightning strikes across Western Washington, both sides of the Cascades and Northwest Oregon, according to the weather service. There were 4,300-4,400 cloud pulses — cloud to cloud strikes — during that time, too.

There’s a chance of continued thunder and lightning in the Cascades through Wednesday afternoon.

Tuesday’s highs across Western Washington were expected to be noticeably cooler thanks to cool air blowing in from the Pacific Ocean. Temperatures were expected to top out in the 60s on the coast and the 70s inland, the weather service said, as conditions remain sunny after morning clouds clear out.

Overnight lows through the midweek will settle in the 50s — a welcome chance to open up windows overnight.

Temperatures will warm slightly on Wednesday as the marine layer shallows and high pressure strengthens overhead: Expect highs near the 70s along the coast and 80s inland, the weather service said.

Temperatures Thursday and Friday will stabilize in the 60s on the coast and 70s to lower 80s inland once again.

“And as we get into the weekend, we’ll start to see more clouds and cooler temperatures,” Felton said Tuesday morning.