La Niña is officially here. What does it mean for winter weather?

(NEXSTAR) – After months of anticipation, La Niña has officially begun.

La Niña conditions emerged in September, the Climate Prediction Center announced on Thursday, and they're expected to last through at least the end of the year.

La Niña typically reaches peak strength in the winter, meaning that's when it has the greatest impact on the type of weather we see — especially precipitation. However, this year forecasters are expecting a pretty weak La Niña.

Here's what that means for winter weather across the U.S. in 2025 and early 2026.

What happens during a typical La Niña winter?

La Niña impacts the position of the polar jet stream, therefore influencing the weather we see on land.

The jet stream divides the country in two, bringing wetter weather to the Pacific Northwest and Ohio