Chicago winter weather outlook; how will La Niña affect snow and temps?

CHICAGO (CBS) -- The National Oceanic and Atmospheric Administration (NOAA) released its annual Winter Weather Outlook on Thursday. The outlook covers meteorological winter from December 2024 through February 2025.

For the Chicago area, the outlook shows the potential for a wetter-than-normal winter with average temperatures expected.

Above-average precipitation is expected this winter due to a developing La Niña weather pattern.

"This winter, an emerging La Niña is anticipated to influence the upcoming winter patterns, especially our precipitation predictions," said Jon Gottschalck, chief of the Operational Prediction Branch of the Climate Prediction Center.

La Niña occurs when cooler-than-average water temperatures are recorded near the equator in the Eastern Pacific Ocean. This phenomenon changes weather patterns globally, including here in Chicago.

La Niña positions the jet stream over the Great Lakes, making for a more active weather pattern. This leads to a wetter-than-average pattern for parts of the Midwest and Great Lakes, while most of the southern United States stays drier-than-average.

On average, Chicago sees about 38 inches of snowfall annually, with January historically the snowiest month. Highs are normally in the low to mid-30s, lows in the teens and 20s, with January also being the coldest month.

NOAA considers Dec. 1 to Feb. 28 as "meteorological winter" therefore, the outlook is for this time period.

"La Niña conditions across the tropical Pacific Ocean may play a role in the weather pattern across North America this winter (leading to more storm systems in the central US). With that said, the ultimate seasonal snowfall and temperatures on a local basis will depend on storm tracks," said officials with the Chicago National Weather Service.