SEATTLE -- Sorry skiers, but La Niña can't last forever...
After two consecutive winters with mountain snowpack-friendly La Niña conditions, long range climate forecasters issued an opposing El Niño Watch Thursday for the upcoming fall and winter.
El Niño winters, on average, tend to be warmer and drier than a typical winter as the jet stream usually stays away, with increased odds of a below average snowpack. It's not always that way (glimmer of hope!), but more often than not, it is the case.
El Niño is part of the 3-7 year "El Niño/Southern Oscillation" (ENSO) when waters in the central Pacific Ocean warm to at least 0.5 degrees Celsius above average. The ensuing warmer waters affect tropical circulations, that in turn influence global weather patterns -- mainly in the fall and winter (peaking in the winter months). La Niña is the opposite cooling effect and "neutral" conditions are in between, and conditions usually swing back and forth through the three options over that 3-7 year period.
Forecasters say that the La Niña from last winter is officially over as waters have warmed to near neutral conditions in the Central Pacific.
Going forward, there are signs of heat already building in deeper waters and forecast models indicate we'll stay in neutral conditions through the summer (where ENSO has little influence anyway since the jet stream is weak).
Odds increase to having a 50 percent chance of El Niño conditions by the fall, and a 65 percent chance El Niño will be here for the winter:
Hey- still a 5 percent chance of La Niña coming back around for a third time! Eh...
In addition to usually having below-normal snowpacks, El Niño winters typically have fewer windstorms, Pineapple Express systems and lowland snow events. Essentially, El Niño usually = boring (to weather fans)...at least overall. There have still been storms of all three varieties during past El Niño events, they're just not as frequent. Instead, El Niño winters are marked by much of the active weather heading into California and across the southern United States.
Silver linings include that while it's too early to predict the magnitude, we can hope this El Niño doesn't end up anywhere near as intense as the past great "Godzilla" El Niño event of 2015 that was ranks anywhere from 1st-3rd strongest on record (depending on your ranking criteria). And this means we can just look forward to the winter of 2019-2020 when we should be coming out of El Niño (skiers and weather fans hope) and on the road back to La Niña. And no real prize for us, but El Niño years also usually suppress hurricane activity in the Atlantic, so maybe the 2019 season there will be benign.
In the meantime, as tradition during past El Niños for skiers and snowboarders, I present some (early) "Emergency Kitten" therapy: