Long range forecasts still trending toward a hotter than average summer in the Northwest

A (rare?) sunny Seattle day. (Photo courtesy: Wild Northwest Beauty Photography)

Reaching 65 degrees this spring has been a challenge, but even so, April is at least leaning toward ending our four-month streak of average monthly temperatures below normal.

And now the new long range seasonal forecast models are thinking we're about to start a new streak on the other side of the ledger, giving better-than-average odds that warmer than normal temperatures will return this summer-- and stick around again for a while.

In the short term, it looks like much of the status quo. The fresh forecast for May shows equal chances of warm/average/cooler than average temperatures in the Northwest -- essentially saying there is no signal in the data showing a reason to lean one way or the other.

April is trending pretty close to average for temperatures (still wetter than normal) so I'd think May would stay on that trend. But if you stretch out the forecast to the three-month period, you'll see the orange "warmer" blob start to stretch toward the Pacific Northwest again. That shade of burnt orange is the lightest "warmer" shade in the palette meaning just a slight lean toward warm for late spring/early summer.

But if you look at the forecast map for the heart of summer, you'll see we're now in darker shades of orange/brown, meaning long range forecasters are indicating a bit higher confidence the warmer forecast will come to fruition.

And then... the orange blobs indicating higher odds of a warmer than normal period just hang out on the long-range maps all the way into spring 2018:

Odds of El Nino jump considerably for this winter

The warmer forecasts, even into next winter, are likely getting a boost from new data giving greater confidence that after a one-year hiatus, we're heading back into an El Nino winter.

The latest odds now have a 65-69 percent chance of El Nino conditions going strong by this autumn -- a pretty decent jump from the 45-51 percent chance the model was giving earlier this month:

And taking the average of various long-term climate computer models gives an average El Nino of +1.0C this winter -- as in ocean temperatures in the Central Pacific about a degree Celsius above normal.

Anything over +0.5C is considered an El Nino, but this would considered a much weaker El Nino than the "Godzilla" El Nino of 2015-16 which had numbers in the +2.5 to +3.0 range (although that one model from Saudi Arabia's KAU University (the light teal square box line) is thinking it might get close.)

El Nino winters tend to be rather mild and boring, with generally warmer than normal temperatures and below normal rainfall and snowpack. Don't worry skiers, I'll have an armada of Emergency Kittens videos at the ready should the forecast come true.

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