Chicago Winter Weather Outlook; How will La Niña affect snow and temperatures?

CHICAGO (CBS) – The National Oceanic and Atmospheric Administration (NOAA) released its annual winter weather outlook on Thursday. The outlook covers the meteorological winter from December 2024 to February 2025.

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

Due to the developing La Niña weather pattern, above-average precipitation is expected this winter.

“This winter, an emerging La Niña is expected to impact upcoming winter patterns, particularly our precipitation forecasts,” said Jon Gottschalck, head of the Climate Prediction Center’s operational forecast division.

La Niña occurs when cooler than average water temperatures are recorded near the equator in the eastern Pacific. This phenomenon is changing weather patterns around the world, including here in Chicago.

La Niña positions the jet stream over the Great Lakes, creating a more active weather pattern. This results in parts of the Midwest and the Great Lakes being moister than average, while most of the southern United States remains dryer than average.

On average, Chicago receives about 38 inches of snow annually, with January historically being the snowiest month. Highs are typically in the low to mid 30s, lows in the 10s and 20s, with January also being the coldest month.

NOAA considers December 1 through February 28 a “meteorological winter,” so the forecast applies to that period.

“La Niña conditions in the tropical Pacific could play a role in weather patterns across North America this winter (leading to more storm systems across the central US). However, final seasonal snowfall and temperatures at the local level will depend on storm tracks,” Chicago National Weather Service officials said.