El Niño vs. La Niña Winters in Colorado

Colorado usually experiences mild winters, but every few years either a La Niña or an El Niño pattern sets up in the Pacific and the state gets a very different winter than usual. This year we're staring down one of the strongest El Niño events ever recorded, so it's worth understanding what that actually means before you buy a pass or book a trip.

What El Niño and La Niña actually are

It all comes down to ocean temperatures in the Pacific near the equator.

During a La Niña winter, those waters run cooler than normal. During an El Niño winter, they run warmer than normal. Either way, the temperature change shifts where the jet stream sets up, and the jet stream is what steers storms across North America.

El Niño tends to push the jet stream south. La Niña tends to hold it north. That's the whole mechanism, and everything else is downstream of it.

The part most Colorado forecasts get wrong

Here's what I had wrong when I first wrote this post back in 2022, and what you'll still see repeated all over the internet: that El Niño means a wetter, cooler, snowier Colorado across the board.

It doesn't. Colorado sits almost exactly on the dividing line, and the effect splits the state geographically.

In an El Niño winter, the southern half of the state is favored. The San Juans in particular (Telluride, Silverton, Purgatory, Wolf Creek) sit closest to that southward-shifted storm track and tend to do well. Southwest Colorado, New Mexico and Arizona are usually the biggest winners.

Northern and central Colorado is a coin flip. Vail, Breckenridge, Keystone, Steamboat and Copper don't get a reliable signal either direction from El Niño. Some strong El Niño years have been great up there and some have been duds.

La Niña roughly flips it. Northern Colorado and the Pacific Northwest get the better odds, and southern Colorado dries out. Last winter was a good example of how ugly that can get, with the state running roughly 60% of average snowfall.

There's one more wrinkle worth knowing. When storms track south, they often pull easterly surface flow in behind them, which loads the eastern side of the Continental Divide. That's why places like Winter Park, Eldora and Loveland can overperform in El Niño years even though they're not in the southern half of the state.

What's set up for 2026-27

NOAA's Climate Prediction Center is putting a greater than 90% chance on a very strong El Niño for this fall and winter. They also give the October to December stretch a 69% chance of going down as a historic event, meaning stronger than anything on record going back to 1950. Pacific sea surface temperatures were already well above average by midsummer.

If the pattern verifies the way past strong El Niño years have, the tilt favors southern Colorado and the terrain near or east of the Divide, with the best snow arriving early (October to December) and late (March and April) and a quieter stretch through the January and February core.

Don't treat any of this as a forecast

This is the part that matters most, and it's the part everybody skips.

ENSO shifts the odds. It does not tell you what's going to happen. CPC's own language is that with an event this large, the chances of seeing El Niño style impacts go up, but they aren't guaranteed. The Colorado Climate Center has been making this point for years: we're a long way from the Pacific, our terrain is complicated, and no single climate pattern runs this state.

Plenty of strong El Niño winters have underdelivered. The 2015-16 event was one of the biggest on record and it whiffed badly in California and New Mexico. So plan around the tilt, but don't bet the season on it.

If you're figuring out which pass makes sense with this setup, I broke that down in detail in my 2026-27 ski pass guide. The short version: the passes that get you south or east of the Divide are worth more this year than the ones that get you to Canada.

Either way, it's still Colorado. Even a bad year has good days in it. Just be ready to chase them somewhere you didn't expect.

Jackson doing a 360 at the terrain park in Breckenridge.