Decent weekend ahead for outdoor activities in the Northwest. So what happened to El Niño? | KNKX

Decent weekend ahead for outdoor activities in the Northwest. So what happened to El Niño?

Jan 18, 2019

An impressive storm was looming offshore Friday morning, promising to bring significant rain and wind to the Puget Sound region. But KNKX weather expert Cliff Mass says it won’t hit too hard and should give way to a relatively quiet weekend, with plenty of breaks to get outside.

“A very deep low center is moving towards the northeast, but the storm is not going to strike Washington state, it’s going to go up along the tip of Vancouver Island,” Mass said.

STORMY FRIDAY

That means Friday will get increasingly cloudy and rain will start sometime in the afternoon, Mass says, with winds really picking up along the coast and over northwest Washington sometime after 4 or 5 p.m.  

The main impacts in the Puget Sound region will come much later, as the storm moves past Vancouver Island. Sometime around midnight to 3 a.m., wind here could gust to 30-35 mile per hour around Seattle.

“So, not as strong as we’ve seen, but it will definitely get blustery,” Mass said. “It’s not going to be the end-all windstorm.”

He says the storm will also bring rain with it during those overnight hours, but, after that, the weekend starts to look pretty nice.

PLEASANT WEEKEND

“The storm gets through; we’ll have a few light showers on Saturday morning. But I think most of the weekend, there’ll only be a 10 to 15 percent chance of rain at any location, partly cloudy skies and temperatures getting up to 50 to 52 here in the lowlands,” Mass said.

He says Monday should also be good. Then, more stormy weather starts coming in again on Tuesday.

“So, a nice break over the weekend — and there’ll be some showers in the mountains, but nothing serious.”

CORRECTION: FEDERAL SHUTDOWN NOT DEGRADING FORECASTS

Last week, Mass talked about the effects of the partial government shutdown on weather science and forecasting. He noted that an important annual meeting of the meteorological society saw poor attendance, a key new U.S. forecasting model release is delayed, and weather research with certain kinds of data has become impossible because the websites that scientists use to access them are down. That is all correct.   

However, Mass says day-to day forecasts are not affected, because key personnel are still working without pay. After further examination, he was able to see that the U.S. global model has not been degraded due to the partial government shutdown.

“Carefully checking the initialization – how the model starts, which is dependent on the data coming in – looks like there’s been no degradation at all,” Mass said.

To triple check, Mass says he had a discussion with NOAA management and learned that sufficient staff are on duty to monitor the initialization and resulting forecast quality. They can make any necessary corrections or adjustments in the model system.

"It's important to note that forecast skill goes up and down due to varying atmospheric configurations and that a decline in forecast skill after the shutdown was a matter of coincidence," Mass said. 

“I should note, during the last few days, the skill has gone way back up again. So it was just a natural variation in skill."

WHAT HAPPENED TO EL NINO?

Speaking of forecast skill, one of the areas where it can vary wildly, is in the long-term predictions associated with El Niño-Southern Oscillation, which uses correlations between sea surface temperatures in the tropical eastern Pacific Ocean to predict seasonal weather patterns.

This year, we have had warmer-than-normal temperatures in the tropical Pacific, which point to the El Niño pattern for the winter. That would bring milder conditions to the Pacific Northwest, with fewer storms and less or no lowland snow. (La Niña correlates with cooler-than-normal sea surface temperatures in the tropical Pacific and tends to line up with cooler and wetter conditions in the Northwest.)

But the data this year has so far pointed to a weak or moderate El Niño, with no official declaration so far. And Mass says he thinks there’s a good chance it won’t happen at all.

“Instead of strengthening this winter, as the National Weather Service forecasts and others were suggesting, the warm waters are actually cooling in the Pacific,” Mass said. “So we don’t appear to be able to get to anything like a moderate or strong El Niño.”

He says, at best, we could have an extremely weak El Niño, but that means the correlation with the weather here in the U.S. will be extremely weak. Mass says that’s the nature of these long-term weather forecasts. A strong El Niño can give us a pretty good idea of what’s ahead.

“But with a weak El Niño like the one we have and one that’s actually lessening in strength, I don’t think we have any forecast skill in the months ahead about what’s going to happen,” he said. “I wish we did, but we don’t.”

To hear the full conversation, you can click on the "play" icon at the top of this post.

Weather with Cliff Mass airs at 9:02 a.m. Friday, right after BirdNote, and twice on Friday afternoons during All Things Considered. The feature is hosted by KNKX environment reporter Bellamy Pailthorp. Cliff Mass is a University of Washington professor of atmospheric sciences, a renowned Seattle weather prognosticator, and a popular weather blogger. You can also subscribe to podcasts of Weather with Cliff Mass shows, via iTunes or Google Play.