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KNKX: Weather with Cliff Mass

KNKX Public Radio

Weather with Cliff Mass is hosted by KNKX's environment reporter, Bellamy Pailthorp featuring University of Washington Professor of Atmospheric Sciences and renowned Seattle weather prognosticator/personality Cliff Mass. Stay up-to-date with the latest weather and more with KNKX!

Weather with Cliff Mass is hosted by KNKX's environment reporter, Bellamy Pailthorp featuring University of Washington Professor of Atmospheric Sciences and renowned Seattle weather prognosticator/personality Cliff Mass. Stay up-to-date with the latest weather and more with KNKX!
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Tacoma, WA


Weather with Cliff Mass is hosted by KNKX's environment reporter, Bellamy Pailthorp featuring University of Washington Professor of Atmospheric Sciences and renowned Seattle weather prognosticator/personality Cliff Mass. Stay up-to-date with the latest weather and more with KNKX!






12180 Park Ave S. Tacoma, WA 98447 253-535-7758


Morning clouds to part for weather that’s hopefully warm enough to enjoy Sound Breeze

A push of marine air from the cold Pacific Ocean that came in Thursday night is bringing morning clouds to the greater Puget Sound region. These low clouds typically burn off by noon, though they can stick around longer. KNKX weather expert Cliff Mass expects Friday and Saturday to provide sunny afternoons, with the clouds opening up to blue skies and temperatures in the mid- to upper-70s.


Gloomy weather moves in — and a long-term forecast shows much of the same ahead

Low clouds have lingered over much of the Puget Sound region in recent days, the latest evidence that this summer stands in stark contrast to the hot, smoky, straw-hat weather of the past two years. KNKX weather expert Cliff Mass says Friday temperatures will only get into the lower 70s. And he says the weekend will be dominated by more of those lower temps, thanks to the presence of an upper level trough.


Overnight rainfall gives way to Seafair weekend sunshine. And what’s with those UFO clouds?

August was off to a warm and sunny start Thursday, with blue skies and nearly perfect summer weather. But people in the Puget Sound region woke up to as much as a half an inch of rain that fell overnight; on the coast, the precipitation totaled as much as an inch and a half. Temperatures dropped quite a bit, too. KNKX weather expert Cliff Mass said a strong front came through and brought along an intense band of showers.


July’s end usually state’s driest time, but rare showers move in amid start of wildfire season

With all the bright sun, blue skies and warm temperatures that have dominated Puget Sound weather recently, it’s a little ironic to see showers in the forecast for Saturday. This weekend is the one anyone planning a major outdoor event in the Northwest typically aims for, says KNKX weather expert Cliff Mass.


Region will be ‘stuck in perfect weather’ as record-breaking jet stream loses strength

"Cloudy and wet" has been the weather mantra so far this July. But KNKX weather expert Cliff Mass say all that is going to change this weekend.


Northwest mellow: clouds, sprinkles and mild temps ahead – and less humidity

Summertime in the northwest can provide a remarkably mellow atmosphere, with lots of clouds, temperatures that hover around 70 degrees and the kind of sprinkles that evaporate on your skin almost as soon as they land. Low clouds often filter the light and you can enjoy the soft focus all around. That’s the kind of weather people in most of western Washington can look forward to for the next several days.


Cool and cloudy skies ahead with air quality to improve after fireworks

There’s a joke in Seattle that summer doesn’t start around here until July 12– three weeks after the solstice and nearly a week after Independence Day. “And I have a feeling that may be true this year,” says KNKX weather expert Cliff Mass after a damp Fourth of July with cloudy skies and cool temperatures around 70 degrees.


'Regional climate modeling' provides clearer picture of climate change impacts in PNW

KNKX weather expert Cliff Mass has been working with a group of atmospheric researchers at the University of Washington hoping to get a better idea of the impact climate change will have on the Pacific Northwest . The group has been conducting "regional climate modeling."


Some June Gloom lingers, but summer solstice brings longer days, ‘rainbow clouds’

Summer solstice, the longest day of the year, is upon us — marked in Seattle by the colorful Fremont Parade (famous, among other things, for body-painted cyclists). Though the sun sets after 9 p.m., it’s not the sunniest part of summer. June in the Pacific Northwest typically means lots of low clouds, our annual "June Gloom." That’s been tempered lately by lots of iridescent clouds — another feature of the season that is fed by the sun’s position, high up in the sky. KNKX weather expert...


Marine air surges in with cooler temps, but wildfire risk remains

The mercury hit a record-breaking 95 degrees at Sea-Tac Airport Wednesday, causing a road to buckle in Seattle’s SoDo neighborhood in a dramatic display of what heat can do to infrastructure. But where there was heat, there were none of the wildfires some folks often associate with warmer temperatures. In a somewhat ironic twist, the risk of wildfires in the region increased Friday as a push of cooler marine air surged in off the ocean, bringing the low clouds locals more often associate...


Rare thunderstorms rolling in, followed by sun and heat; and a D-Day weather lesson

Many people woke up to big patches of blue sky in the Puget Sound region Friday, especially in the South Sound. But KNKX weather expert Cliff Mass says the sun breaks will yield to cloudier weather as low pressure moves into the region. And a rare batch of thunderstorms is expected to douse and excite parts of the state.


How reliable are those extended, seasonal forecasts?

It's going to be a beautiful several days, and we can expect lots of sunshine. But as we look toward what's expected in the next week or month, there is some uncertainty. In KNKX weather expert Cliff Mass' blog post this week , he talks about the reliability of extended forecasts. He says forecasting models are "quite good" out about a week.


Sunshine lies ahead after a few drizzly days, but what do the dry conditions mean for the state?

There will be a few more wet, cool days before the weather transitions on Sunday to warm and sunny. The drier conditions have many state officials worried about the wildfire season. Gov. Jay Inslee announced a drought declaration this week, but KNKX weather expert Cliff Mass says things may not be as bad as they seem.


Local rain — and California’s record showers — mean healthy water supplies, delayed fire season

The wet season has returned to Western Washington, with showers and all out rain alternating through early next week, a continuation of the pattern we’ve been seeing for a while. “But none of that’s going to be that heavy. And the reason is, most of the weather is going into California,” said KNKX weather expert Cliff Mass, who teaches atmospheric sciences at the University of Washington.


Enjoy the heat. Offshore flow brings cooler temperatures Sunday — and lots of rain.

There’s a key weather battle that plays out every summer. It determines how warm (or hot) conditions can get in the Puget Sound region. It’s the tug of war between onshore and offshore flow, says KNKX weather expert Cilff Mass.


Warmer weather on its way as 'low cloud season' sets in

It’s a prequel to the infamous June Gloom — that dreary period of typical Northwest, in-between weather, with clouds that hang low and persist for weeks without providing any meaningful rain. KNKX weather expert Cliff Mass says May actually marks the start of the "low cloud season" that dominates in June. And we should expect it to extend from now until mid-July.


Enjoy 'perfect' day ahead, and the showers too — smokey season looms

Clear blue skies and sunshine got the weekend off to a beautiful start in Western Washington. Both are expected to stick around all day Friday, before shifting to showers Saturday morning.


Rain relents, and weather expert shares Puget Sound convergence zone primer

If you’re tired of all the precipitation that has been raining down on the Northwest since early April, take heart. KNKX weather expert Cliff Mass promises this weekend will be dry and even a bit sunny.


April showers douse the Northwest, building snowpack and filling reservoirs

Major April showers are dousing the Pacific Northwest, and they're bringing more than flowers. Environment reporter Bellamy Pailthorp talked with weather expert Cliff Mass, who provided the latest forecast and an update on the water situation in the region following an unusually dry March.


Rain returns as region recovers from arid March, but UW team shines bright in forecasting contest

Stay indoors or get out the Gore-Tex this weekend if you’re going outside in Western Washington. KNKX weather expert Cliff Mass says a triple whammy of weather systems will douse the region, providing some relief from our record-dry March and only a few dry periods over the next few days. “We’re going to have three rain events over the next 72 hours,” Mass said Friday morning. “The drought of March is going to be over.”