Weather with Cliff Mass

University of Washington Professor of Atmospheric Sciences and renowned Seattle weather prognosticator/personality Cliff Mass has joined KPLU’s roster of commentators.

"Weather with Cliff Mass", our new five-minute feature hosted by KPLU's environment reporter Bellamy Pailthorp, airs every Friday beginning at 9 a.m. immediately following "BirdNote", and will repeat twice on Friday afternoons during All Things Considered. It is also available as a podcast on

Jeff Lilley

This summer, we’ve already beat the record for the hottest July and August ever in the Seattle area. And this weekend, we can expect to build on that trend with clear skies and warming temperatures pushing toward what will likely be the hottest full summer season on record, says KPLU weather expert Cliff Mass. 

“We’ve been having the best summer on record here in Washington state, and it’s not going away,” Mass said.

Tim Durkan

It won't be long now. 

Fall is just around the corner, says KPLU weather expert Cliff Mass, and that means the holiday weekend won't be all sun. 

"We'll see a different weekend than we've been used to in the past," he said. "Temperatures are going to drop way back. No more 80s."

Elaine Thompson / AP Photo

Keep the sunscreen and swim trunks handy. The clouds are melting away and the forecast predicts another hotter-than-normal weekend with temperatures above the mid-70s that are typical for this time of year.

KPLU weather expert Cliff Mass says we are experiencing one of the hottest summers on record and could soon chart the hottest one in Northwest history.

Aaron Brethorst

A week of rain has turned what was a dry summer into a normal one, says KPLU weather expert Cliff Mass.

But don’t let the clouds and drizzle get you down. Mass says the forecast will progressively warmer and sunnier over the weekend.

Tim Durkan

Go ahead and gloat. We’ve got one of those hot, sunny August western Washington weekends ahead that make it worth living here despite the long, dark winters.

Low clouds will melt away, says KPLU weather expert Cliff Mass, as temperatures steadily rise over the weekend, hitting 90 maybe even as early as Sunday and certainly by Monday.  

“A warming period is going to happen,” said Mass. “And that’s because a trough that brought us cooler temperatures this week is moving off and a pretty high-amplitude ridge is building in its place.”

Elaine Thompson / AP Photo

There will be plenty of sunshine for Seafair weekend, says KPLU weather expert Cliff Mass, but dry conditions and a chance of lightning could mean trouble for firefighters.

Tim Durkan

If you love sunshine, Friday’s the day to get out and enjoy it.

The cooling trend we’ve been experiencing will continue this weekend and even bring some rain with it, says KPLU weather expert Cliff Mass.

Tim Durkan

Make sure you’ve refilled the ice trays. KPLU weather expert Cliff Mass says it’s going to get hot in the days ahead.

Doug Mahugh

Sunny skies on the Fourth of July are not something to take for granted in Seattle. But revelers can count their blessings this year, as the clouds are expected to burn off and give way to a decent day for picnics and fireworks displays, says KPLU weather expert Cliff Mass.

“Much better than some other Fourth of Julys,” Mass said.

Tim Durkan

Keep your rain gear handy if you’re headed outside this weekend. KPLU weather expert Cliff Mass says we’re starting to pay for the drier-than-usual June we’ve had this year.

But Mass says sunny days are around the corner; things will improve by the Fourth of July weekend.

Tim Durkan

The nude cyclists at Seattle’s Fremont parade can look forward to comfortable summer temperatures on Saturday afternoon. And it might even be a bit too hot for runners at the Rock 'n' Roll Marathon, says KPLU weather expert Cliff Mass.

A weak front has passed through, says Mass, and the clouds and sprinkles are expected to subside in time for the summer solstice Saturday.

Tim Durkan

Friday will bear the worst of the weekend weather, says KPLU weather expert Cliff Mass, but don’t expect sunshine on Father’s Day.

The rain returned on Friday with a “fairly good drenching” — “the first substantial rain” in nearly two weeks — and the clouds are expected to stick around for most of the weekend, Mass said.

Tim Durkan

It appears the infamous June Gloom will spare us — at least for now.

“Normally this month, we have June Gloom: cloudy skies, temperatures in the 60s. But this year, it’s been unusually nice, [with] temperatures above normal and extraordinary amounts of sun,” Mass said.

Erin Hennessey

It’s time to get out the sunscreen and summer clothes.

KPLU weather expert Cliff Mass says we have a beautiful weekend ahead of us.

Jean-Pierre Chamberland

Well, it's complicated.

The forecast for our long holiday weekend starts wet, then dries out, then gets downright motley as we move into prime barbecue territory.

Aaron Brethorst

The weekend curse is back, according to KPLU weather expert Cliff Mass.

After a week of unseasonably warm and dry weather, reaching up into the 80s more than once, temperatures are set to drop about 10 degrees on Friday, and step down another 10 or so over the weekend.

Denise Walker photo

“First things first,” said KPLU weather expert Cliff Mass. “For Mother’s Day, it looks good.”

Mass predicts sunny skies and temperatures of at least 70 “and maybe even into the low 70s” for Sunday.

But before then, there’s some rain to get through.

AP Photo

It seems the curse of the wet weekend is upon us again.

This week's unseasonably hot transition from April to May is giving way to much cooler temps and heavy rain on Saturday and Sunday, says KPLU weather expert Cliff Mass.

It comes on the heels of a gloriously sunny and hot work week.

C4Chaos / Flickr

Don’t put your parkas away just yet. 

It’s classic April weather this weekend with lots of showers but plenty of sunbreaks, too, according to KPLU weather expert Cliff Mass. 

Saturday, in particular, is going to be nice, says Mass, who teaches atmospheric sciences at the University of Washington.

Ted S. Warren / AP Photo

If you’re planning any outdoor fun this weekend, Sunday’s your best bet, says KPLU weather expert Cliff Mass.

The famous Puget Sound convergence zone has been dumping rain in the greater Seattle area, with some places in the foothills of the cascades getting as much as 4 inches in the space of just six hours on Thursday afternoon. Mass, who teaches atmospheric sciences at the University of Washington, says there will be a break from that today, but not for too long.

Tim Durkan

Get out your shades and sunscreen: this weekend promises to be mild and very sunny, says KPLU weather expert Cliff Mass.

“It’s gonna be quite good,” said Mass, professor of atmospheric sciences at the University of Washington.

Elaine Thompson / AP Photo

Got outdoor plans this weekend? You’ll want to make use of your Saturday morning, says KPLU weather expert Cliff Mass.

Elaine Thompson / AP Photo

This weekend's rain caused parts of western Washington to see the wettest March on record as was predicted by KPLU weather expert Cliff Mass

"My lawn has turned into a carpet of moss and my deck is now green," Mass said on Sunday.

Photo by Neil Banas / Flickr via Compfight

Friday's steady rain is contributing to what may become a record-breaking March for total rainfall in many places in the Northwest.

KPLU weather expert Cliff Mass says a wet front is coming through western Washington.

Jonathan Cooper

Spring has officially arrived, but warmer temperatures have not. Those warmer days lie ahead, but first we’ll have to get through a cool and wet weekend, says KPLU weather expert Cliff Mass.

Tim Durkan


Just when you thought spring had arrived in the Pacific Northwest, winds and wet weather are sweeping in.

We're in for another wet weekend, says KPLU weather expert Cliff Mass — but not without sun breaks.

Jaymar Turner photo / Compfight/Flickr

After a record-breaking week of strong rain, Friday will bring a bit of reprieve. But the rain will return this weekend, even in the mountains, says KPLU weather expert Cliff Mass.

Still, there is good news: come next week, we’ll start transitioning into spring.

Martha Kang / KPLU

Soak in Friday’s sun and spring-like temperatures while you can, because they won’t stick around this weekend, says KPLU weather expert Cliff Mass.

Mass says snow is once again in the forecast for parts of western Washington.

Shannon Kringen / Flickr via Compfight

The weekend forecast includes chances of snow, but nothing's for certain, says KPLU weather expert Cliff Mass.

"This is a hard one," said Mass. “There’s a lot of uncertainty here. I’ll tell you that right in the beginning.”

Jim Stiles

We’re getting the “weather we need,” so get ready for a wet and windy weekend, says KPLU expert Cliff Mass.

“Our water supply was well below normal,” said Mass, who teaches atmospheric sciences at the University of Washington. “Very rapidly, the snowpack is getting replenished in the mountains. The reservoirs are filling. And by the end of this week, I don’t think we’ll have to worry water for this summer or the coming fall.”