Weather with Cliff Mass

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If Friday’s clouds and drizzle are getting you down, hang in there. KPLU weather expert Cliff Mass says a warm, sunny weekend is in store as soon as the work week ends.

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Fall has officially arrived and we can feel it. Temperatures have dropped. But KPLU weather expert Cliff Mass says Friday’s rain will quickly move east, making way for sunny skies this weekend.

“Precipitation will lighten up certainly by the early afternoon here on the western side,” Mass said. “So, not a warm day, but at least it will be dry the second half,” he said, predicting temperatures only reaching the lower to mid-60s. “So definitely below normal and cooler than what we’ve had before.”

An Improving Trend This Weekend

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“No one’s going to mistake this weekend for July,” quipped KPLU weather expert Cliff Mass. He says Saturday will be the best day of a mostly cloudy weekend that will become increasingly wet.

Friday, Mass says there will be some showers floating around, mostly offshore, and clouds elsewhere. “For most people, it’ll be relatively dry – much drier than yesterday,” He said. “So, you know, an okay day.” Temperatures will get into the upper 60s.

Get Your Outdoor Fun In On Saturday

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You may have heard that predicting the weather in the Pacific Northwest is especially difficult. 

KPLU weather expert Cliff Mass says that may have been the case in past decades. But the truth now is, it’s not.

"In fact, that’s one of the great fantasies of the weather world: that somehow it’s really hard to predict here, the skill is much less than other places, because of the big Pacific," Mass said. "That’s, in fact, not true."

An Ocean's Influence

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If your plans for the long Labor Day weekend include outdoor activities, be ready for a chance of rain on Sunday. Other than that, it will be mostly sunny and warm, says KPLU weather expert Cliff Mass.

“There will be a lot of sun. But one day will be cloudy and maybe a little bit of rain and that’s Sunday,” Mass said.  

Keep That Raingear Handy Friday

Friday morning’s residual clouds were burning off by afternoon, leaving the lowlands basking in plenty of sun. Mass warned of fewer sun breaks in the mountains.  

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Generally cooler temperatures this weekend should help firefighters gain headway in massive, stubborn wildfire in Eastern Washington, said KPLU weather expert Cliff Mass.

"Right now we have a little bit of a cool-down going on" Mass said. "We'll see a step-down into the mid 70s (Friday) some low clouds and most of those will burn off during the day."

The weekend will see a slight uptick in temperatures with temperatures in the lower 80s. Next will a major cool-down will begin. "Cooler than normal for much of the week and even a chance of some rain later in the week -- especially on Thursday and Friday," he said.

Mass said that slight, two-day rise in temperatures won't do firefighters any good but come next week, they should catch a break. "If they can get to Monday," he said, "we'll see cooler temperatures and more humidity over the fire area." 

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Friday’s rainy start was the first part of “a theater piece in two acts,” said KPLU weather expert Cliff Mass. “The first act happened this morning.”

The showers that doused the northwest overnight will return in the afternoon, Mass says, accompanied by “all kinds of thunderstorms and heavier rain. ”  

He predicts those will start revving up sometime between 3 p.m. and 4 p.m. “And I would expect rain around dinnertime into the early evening.”

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If sunshine is something you crave on weekends, best to get out and enjoy it on Friday if you can.

The forecast gets cloudy on Saturday, with showers increasingly likely on Sunday.  In fact, KPLU weather expert Cliff Mass is blogging this week about how this August is off to a much cooler and wetter start than is typical.

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The Puget Sound is going to continue its California weather imitation for another weekend in what already is a record-breaking summer, said KPLU's weather expert Cliff Mass.

"This is going to be the warmest summer in the memory of virtually everybody," Mass said. "You have to go back to the 1930s to get temperatures that are even similar to this."

Need proof? The region on Thursday beat the all-time record for 90-degree days in a summer with 10 days. The old record was nine.

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Statistically speaking, it generally is the driest time of year in western Washington. Because of this, late July into early August is the most popular time for outdoor weddings and family reunions in the region.

But showers are in the forecast this weekend. If you were thinking of getting outdoors, you’ll have to travel east over the mountain passes, advises KPLU weather expert Cliff Mass. He says there’s a band of precipitation approaching from the west that will definitely dampen the region, pretty much anywhere west of the Cascades.

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The recent bout of breezes and cooler temperatures feels like back to normal in the Pacific Northwest with even a few overcast days and sprinkles thrown in.  

But the mercury will rise quickly this weekend, returning the region to above-normal heat for this time of year. Expect clear skies and a spike in temperatures as a ridge of high pressure builds above us, said KPLU weather expert Cliff Mass.

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A cool breeze brought relief to the region last night with apartment dwellers in the Belltown neighborhood enjoying outdoor music on patios or sitting on nearby ledges and breathing a bit easier.

The wind swept the smoke out the sky, improving air quality while dropping temperatures by 15 degrees in a single day, said KPLU weather expert Cliff Mass. This stands in sharp contrast to the past three weeks which saw a long series of record-breaking temperatures. 


Inevitably, fireworks start going off in the first week of July, even before the Independence Day holiday has begun. 

They’re not just loud, says KPLU weather expert Cliff Mass, they’re dirty.

“We often see a spike at the air quality measuring stations of very small particles (of pollutants,)” Mass said.

He notes there is typically a gigantic jump in levels measured on the 4th of July later in the day.

“And some places it’s the worst air of the year,” he said.

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If you live in the Pacific Northwest, a scary lightning strike isn’t very likely.

But there was one recently in Seattle’s Arboretum that could be a case study in a text book.

“The lightning bolt went right down the moist center of the tree, blew the tree out and so it just spread apart,” Mass said.

He says in this case, the lightning hit just right and heated up the moisture at the core of the tree, causing steam to form and blast it into pieces.

“Pieces of that tree were sent off as projectiles, hundreds of feet away,” and embedded themselves deeply into the ground because of the force of the blow.

“It was amazingly dangerous,” Mass said.

“And there’s been explosive trees around here before; this is not the first incident. But it’s probably the most dramatic I’ve ever seen,” he said.

He says he’s never seen anything like it, at least not in nature.

“It looked like one of those onions you get at Safeco Field,” he said.

In this week’s episode Mass explains why lightning strikes are relatively rare here, why the recent one near the Arboretum visitor center was so forceful and how to position yourself on the off chance that you do get caught in a lightning strike.

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The weak, rainy front that stopped for a short visit the Puget Sound is moving along and leaving more warm dry weather in its wake, said Cliff Mass, KPLU's weather expert.

A small system between Seattle and Everett might bring brief showers later on Friday. But areas south of Seattle -- particularly areas hosting major golf tournaments -- should expect warm, dry weather for the whole weekend.  Saturday and Sunday will start with morning clouds that will clear as the day progresses, Mass said.

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The mid-week warm weather has been replaced by a cool swath of marine air that will linger for the early weekend and then dissipate into warmer temperatures come Sunday and Monday, said KPLU weather expert Cliff Mass.

Expect temperatures in the upper 60s to the low 70s with morning clouds for Saturday and early Sunday, Mass said.  The warmer temperatures -- potentially into low 80s -- will return briefly later Sunday and Monday. Cooler weather then will reassert itself late Monday.

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If your Memorial Day weekend plans include a hike in the mountains, be prepared for rain. And if you’re hanging around the Northwest Folklife Festival or elsewhere in the lowlands, expect showers, says KPLU weather expert Cliff Mass.

He says it’s a continuation of a pattern that started on Thursday and continued into Friday morning.

“We had a lot of low clouds moving in to the west of the Cascade Crest,” Mass said.

“There’s an on-shore pressure gradient and so there’s stratus and strato cumulous (clouds) at lower levels. But at upper levels, we’re getting flow still coming off the mountains,” he said.

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If you were out in shorts last weekend, slathering on sunscreen, be prepared for a different kind of weather this Saturday and Sunday.

“There won’t be a lot of sun tomorrow for most of Western Washington. Maybe a few sunbreaks, but not much more than that,” says KPLU weather expert Cliff Mass, a professor of atmospheric sciences at the University of Washington. “This is going to be kind of a so-so, middle-of-the-road weekend.”

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Friday is the best day of the weekend to recharge your vitamin D stores by soaking up sun and warmth, says KPLU weather expert Cliff Mass.

But the whole weekend looks pretty glorious. He says the small amount of clouds present are limited to places near the water.

“A few fog patches along the coast, those are burning off, so – great day,” he said of Friday’s weather. “Temperatures will get into the lower to mid-seventies, with total sun, no precipitation, so – wonderful.”

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Enjoy the sunny weekend –but keep your rain gear ready – we’re going to have a nice scenario for gardening and other outdoorsy pursuits this weekend.

That’s according to KPLU weather expert Cliff Mass, who is also excited about the recent news of El Nino and La Nina. (Click “listen to our podcast and hear his information about all that.)

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Windy weather this weekend will make umbrella use a bit problematic, but you probably will need a parka or other rain gear, at least for the next day or so.

“We have an upper level trough over us and that brings cold air and unstable conditions where we get the cumulous (puffy clouds) and thunderstorms developing,” said Mass.

And so on  Friday, Mass says expect some showers, especially in the mountains and South Sound.

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Gardeners can get out the gloves and seed but skiers will have to stow their gear. Clear skies and warm temperatures headed our way will melt the small blanket of new snow from last week, said KPLU weather expert Cliff Mass.

“On Thursday, we had almost complete sunshine,” Mass said, adding that his team of meteorologists at the University of Washington measures the amount of solar radiation coming in. “And there were virtually no clouds getting in the way of our sensor, so it was total, maximum sunshine.”

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Cliff Mass is one of the region’s clearest communicators about the weather. We talked this week about the impacts of climate change in the next century. He has indicated in the past that we are relatively lucky when it comes to climate change.

But there will be changes, in the future.

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The thunderstorms that hit our region a couple of days ago are a classic sign of spring in the Northwest. And the temps we’ve been experiencing lately are entirely normal for this time of year, says KPLU weather expert, Cliff Mass. 

So if you’ve been shivering and wishing for the balmy temps that made Monday seem like summer, Mass says you might as well get used to it for a while. We’re in for a cloudy, unsettled weekend, with “plenty of clouds around," according to Mass.

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Spring is officially here.

The vernal equinox means that days and nights are of equal length. From here on out, the days will get longer. It’s also a great season for cloudgazing, which KPLU weather expert Cliff Mass knows a lot about.

This weekend will bring plenty of opportunities for admiring all kinds of clouds.

“Clouds like altostratus and altocumulus that will be thickening in,” Mass said. “Another cloud that’s very popular around here we’ll see tomorrow morning: the stratocumulus – low clouds that have these heaps and clear skies in between.”

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Get your tee shirts and shorts out. You'll need them as we head into the weekend. 

That’s the word from KPLU weather expert Cliff Mass, who says the warm air above us is “warm enough that if it was completely sunny today, many people would experience temperatures getting into the lower 70s.”

Possibility Of Record-Breaking Temps Friday

The big question, Mass said, is how much the clouds will thicken up on Friday around the Puget Sound region.

If they’re thick, Mass says temperatures will hit 66 or 67 degrees, which is way warmer than normal.

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If rainy weather makes you blue, don’t worry. The sun will come out on Saturday, and the weekend will bring us back to the pattern of sunshine. 

KPLU weather expert Cliff Mass sounded a bit surprised to see rain coming down on Friday, amid one of the sunniest winters we’ve experienced in a long time.

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Friday’s clouds and sprinkles are moving out, and sunshine and more warmth are coming in this weekend.

And you can expect the pattern of unseasonably warm weather we’ve been having in western Washington to intensify over the next week, says KPLU weather expert Cliff Mass.

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Mother Nature is serving up sunny skies and amazingly warm temperatures for the long Valentine’s Day weekend.

KPLU weather expert Cliff Mass says conditions will be “perfect for conditions hikers, bikers and gardeners; let’s not mention skiers."