Weather with Cliff Mass

Weather with Cliff Mass

From KPLU

Weather with Cliff Mass - our new five-minute feature hosted by KPLU's Enviornment reporter, Bellamy Pailthorp, featuring University of Washington Professor of Atmospheric Sciences and renowned Seattle weather prognosticator/personality Cliff Mass.More from Weather with Cliff Mass »

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Why Is August Our Hottest Month – Not June?

An excessive heat warning has been in effect since Thursday this of week and temperatures are expected to hit the 90s in places around the Puget Sound region through Saturday. It will be sunny and hot all weekend long. And the heat wave comes as no real surprise; This is typical weather around here for August, when we expect our hottest temperatures of the year. But why now? Shouldn't it be in June, when the sun is strongest? KPLU weather expert Cliff Mass agrees that it's an interesting question. He says it's counterintuitive that the hottest summer days in the Northwest generally come more than a month after the solstice, when the sun is highest in the sky. Sun's Warming Effect Takes Time "The strongest sun is clearly around June 21st, near the solstice," Mass said. "The intensity is the strongest, so you might expect the warmest days to be when the sun's the strongest. But it's not." The warmest days here in the Northwest — and in fact in many places – are actually in early August.

Northwest Perfect: Sunny, Clear Blue Skies Continue This Weekend

It's hard not to gloat about Northwest weather in a week like this one. And KPLU weather expert Cliff Mass says the glory of blue skies and warm but comfortable temperatures is set to continue for most of the coming weekend. "We're stuck in this pattern of near perfection of weather," Mass joked. "We're in the 70s and low 80s and dry conditions while the rest of the country's in heat and humidity and thunderstorms. So we can't complain," he said. Warmest On Friday Mass, who teaches atmospheric sciences at the University of Washington says Friday will be the warmest day of the weekend, with temperatures expected to reach the low to mid-80s. "Yesterday got to 81 at SeaTac, so we should beat that today," he said on Friday. "That's due to a ridge of high pressure over us." He says over the course of the weekend, that ridge will slowly slide towards the east. That will cause temperatures to peak on Friday and gradually cool over the next few days. A Fine Day Saturday Mass says Saturday will

Cooler Than Normal Seafair Weekend With Rain Expected Late Sunday

The first weekend in August is statistically one of the driest and warmest weekends in the Pacific Northwest. It also marks the height of outdoor summer fun in Seattle as Seafair's hydroplane races hit the water and the Blue Angels show off their daredevil moves in the skies above. KPLU weather expert Cliff Mass says this year's Seafair Weekend forecast is for cooler than normal weather and even some rain. "But the rain's going to hold off till the end of Sunday, so I think most activities will be fine," Mass said. The basic situation, Mass says, is that there's an upper-level trough of low pressure approaching the Northwest. It's bringing in temperatures that are 5 to 10 degrees lower than typical. "It's unusual for this time of year, but it's there. And as that trough approaches, it's going to bring cooler than normal air into us. And later in the weekend, I think we'll see rain that'll extend into Monday," Mass said. He says temperatures on Saturday will probably get up to 68

How Northwest Mountains Make Their Own Summer Storms

Have you ever noticed that oftentimes on summer afternoons, big clouds seem to form right over the Cascades or the Olympics, almost like the mountains have their own weather systems? They do. "It's true," says KPLU weather expert Cliff Mass. "Many summer afternoons, we see puffy cumulous clouds starting to form over the upper slopes of the Cascades. And they increase in width and height during the afternoon and quite frequently you have a few showers there – even some lightning," he said. "And so that's real, we see it over the Cascades, we see it over the Olympics." Mass, who is a professor of atmospheric sciences at the University of Washington, says the physical structure of mountains can create their own weather systems, caused by the way air flows around them. "What happens is during a normal summer day, the slopes of the mountains heat up," Mass says. This causes the air to flow up the slopes on both the eastern and western sides of the Cascades or Olympics. And then the upward

Despite A Wet Start, Classic Northwest Sunshine Dominates Weekend Forecast

"Liquid sunshine" made an ample appearance as the Northwest weekend got off to a wet and cloudy start. But KPLU weather expert Cliff Mass promises warmer temps and clearer skies as the weekend progresses. In fact, he says we're headed into what is usually one of the nicest times of year and he expects it won't disappoint. "We're about to go into an extended dry spell," Mass said.

Despite A Wet Start, Classic Northwest Sunshine Dominates Weekend Forecast

Another Cloudy Northwest Weekend; Typical Summer, With No Heat Waves In Sight

Mid-July is well into what most people in the Pacific Northwest consider the summer season, which can be delightfully sunny and warm. Last year, it was characterized by record heat. Not this year. KPLU Weather expert Cliff Mass says it will be pretty gray for most of this weekend. And though it feels cool compared to last year, it's actually relatively average in terms of temperatures.

Another Cloudy Northwest Weekend; Typical Summer, With No Heat Waves In Sight

Summer Seems To Be Arriving Late In Western Washington; Call It 'Januly'

Expect the cool, cloudy skies and rain to continue this weekend. KPLU weather expert Cliff Mass says the unseasonable weather is so extreme this year, he's coined a new phrase for it: "Januly." He says though it's not quite as cold as January, the patterns he's seeing in the atmosphere resemble ones more typically seen in winter. "I looked at the satellite picture and I couldn't believe it," Mass said. "It looks identical to the kind of satellite images that we see in January — this huge cyclone, this spiral of clouds, a front coming out of it. So, you couldn't tell the difference between the satellite picture of today [Friday] and that of January, they look that close." To be fair, he says the similarity stops with the temperatures. But other conditions sure don't feel much like summer. "It won't be quite as cold as January, but there will be plenty of precipitation and lots of clouds," Mass said. Gray And Cool On Friday On Friday, he says there will likely be a break in real rain,

Summer Seems To Be Arriving Late In Western Washington; Call It 'Januly'

A Classic July 4th Weekend: Mostly Cloudy And Mild, But Clear Skies In Time For The Fireworks

This Independence Day, don't expect the scorching heat we've seen in recent summers around here. But it will be pleasant this year, with fine conditions for viewing fireworks, says KPLU weather expert Cliff Mass. "You know this is going to be a classic July 4th weekend," Mass said, "where there's a lot of clouds and a few sprinkles."

A Classic July 4th Weekend: Mostly Cloudy And Mild, But Clear Skies In Time For The Fireworks

Sunnier Skies And A Warmer Weekend Ahead As June Gloom Subsides In The Northwest

It's been cool, damp and showery in the Northwest lately, with a classic pattern of June gloom overshadowing the official start of summer earlier this week. But that's about to change. KPLU weather expert Cliff Mass says the heaviest rains are over for a while. He says the recent clouds and precipitation were caused by an upper-level disturbance moving through the region. Mass says that will pass through the area by Saturday morning.

Sunnier Skies And A Warmer Weekend Ahead As June Gloom Subsides In The Northwest

Spring Mix: A Rainy Saturday, But Plenty Of Sun For Father's Day In The Northwest

Prepare to get wet on Saturday. But don't lose hope. The sun will be back on Sunday, just in time for Father's Day festivities as Northwest skies serve up a spring mix of rain and shine this weekend. KPLU weather expert Cliff Mass says Friday's conditions should set the tone. You'll want to keep sunglasses as well as a rain slicker handy. "It's sunny from Seattle northward," Mass said. But he says conditions will start to change come Friday afternoon. He says clouds that began over Portland and continue into Olympia are starting to move into the Puget Sound region as an upper-level trough of lower pressure moves northward, likely bringing a few light showers with it in the morning. But Mass says the real threat for precipitation on Friday will arrive later in the afternoon, caused by instability in the atmosphere. Friday: Cumulous Clouds And Convection Showers "You noticed a lot of those cumulous clouds that have been puffing up during the afternoon? That's because the air aloft is

Spring Mix: A Rainy Saturday, But Plenty Of Sun For Father's Day In The Northwest

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