Does a La Niña winter forecast spell a Seattle Snowmageddon?

La Niña winter forecast in WA

A La Niña weather pattern is expected in the Pacific Northwest this winter. FOX 13 Meteorologist Abby Acone breaks down what La Niña winters have looked like in the Seattle area in previous years, and what we could expect this year.

SEATTLE - When we're talking about El Niño or La Niña, what we're doing is looking at water temperatures in the equatorial Pacific Ocean, and looking at how it might affect weather across the world.

For us here in North America, a La Niña pattern tends to increase the chances for a cooler and wetter-than-normal winter in the Pacific Northwest. For the desert southwest, the four corners and California, they will expect a warmer and drier-than-usual winter. This is going to be the opposite pattern of what we saw last winter.

How will a La Niña winter impact the chances of snow in Seattle?

A La Niña winter in Seattle means the odds of seeing at least some lowland snow is increased. This does not guarantee that it will be a super snowy winter.

We did some homework for you, looking back at the last 10 La Niña winters to see how much snow we had at SeaTac. It appears we had major snowfall, 10 inches of snow or more, in half of the last 10 La Niña winters. During the La Niña winter of 2020-2021, more than a foot of snow fell in Seattle.

How long does a La Niña pattern last?

While an El Niño weather pattern lasts about a year, a La Niña weather pattern lasts two years or more. Recently, we had three back-to-back-to-back La Niña winters.

When we are talking about this type of big-picture pattern, we're looking at overall averages for a season. This does not mean that every day will be wet, cool and soggy. There could be many mild and dry stretches this winter.

In general, a La Niña winter could increase our chance for a robust mountain snowpack, which is great news for skiers, snowboarders and the environment.