Expect a strengthening El Nino this winter across Western Washington and the North Sound, according to the latest seasonal weather outlook from the National Weather Service Climate Prediction Center. The eastern Pacific tropical waters west of Peru, near the equator, have warmed about 2.5 degrees Celsius or about 4 degrees Fahrenheit above average and are still climbing. This warming, according to the CPC, is the result of weaker than normal easterly trade winds across the Pacific.
El Nino sea surface temperature forecast guidance from around the world all indicate El Nino to strengthen more through the end of the year. In an El Nino Advisory statement from the CPC, there is a greater than 90% chance of a very strong event by the end of this year, and a near 70% chance this El Nino will be a record event, with records going back to 1950.
The Winter Weather Outlook
The just released seasonal weather outlook reflects a strong El Nino episode through this winter. During El Nino, the Pacific storm track spends more time moving into California and across the southern tier of the U.S. mainland. As a result, the Pacific Northwest usually has a warmer than average winter with a slight edge toward drier than average conditions. That kind of southern winter season storm track, leaves the Pacific Northwest with good odds of warmer than average temperatures and no real trend on precipitation through this winter. The 3-month winter period of December through February shows a 60-70% chance of warmer than average temperatures – about as high as it’s ever been for such a seasonal weather outlook.
For the southern half of the country, the odds are strongly in favor of above average and much needed precipitation to help alleviate current drought conditions. For the Colorado River basin, the rise in precipitation and mountain snow should help start a rebound of much needed water in the river. The other side of that coin though is a growing threat of too much rainfall at once, resulting in flooding and landslides.
North Sound Impacts of El Nino
A big impact of El Nino and its warmer than average conditions implies another below average mountain winter snowpack, not good news for skiers and water managers. Another subpar mountain snowpack would make that 5 years in a row, leaving more limited water supplies for agriculture, fish, electric power generation, and drinking water, and the likelihood of another active wildfire season with more smoke and air quality issues next year.
Heading well into next year, this El Nino episode is likely to wane, yet is anticipated to leave an El Nino hangover. The temperature outlook all the way through to near the end of 2027 shows ongoing chances of warmer than average temperatures, another reason for concern about next year’s wildfire season.
With Halloween approaching, the term El Nino often generates unpleasant scary implications. Yet in fact, of the three types of La Nina, Neutral and El Nino conditions in the eastern Pacific tropical waters, El Nino tends to have more limited hazardous winter weather than La Nina and Neutral conditions in the Pacific Northwest.
La Nina is when those same eastern Pacific tropical waters are cooler than average, and Neutral conditions–that don’t indicate either La Nina or El Nino–are close to average. Both of these conditions also adjust how the North Pacific storm track behaves, spending more time moving into the Pacific Northwest versus California.
When it comes to hazardous fall and winter weather in the Pacific Northwest – flooding, strong damaging wind storm, and lowland snow and ice, El Nino ranks last compared to La Nina and Neutral. That does not mean these hazardous weather events do not occur, they just occur less frequently.
Prepare Now
Regardless, now is the time to prepare for whatever hazardous fall and winter weather lies ahead. Visit ready.gov , Washington State Emergency Management, or your local county or city emergency management websites for helpful readiness information for your home, car, business and pets.
Again, preparing ahead of time before a significant storm arrives or big earthquake occurs is a good time to get ready, particularly while needed supplies are readily on hand from retailers right now.
