More snow predicted for the Chicago area this winter
CHICAGO (CBS)—New winter outlooks from the NOAA Climate Prediction Center released Thursday call for a typically cold winter across the Upper Midwest. Wetter-than-normal weather is likely, which could mean more snow than usual in northern Illinois and northwest Indiana.
NOAA's seasonal outlooks are driven partially by the El Niño/La Niña cycle, a naturally oscillating phenomenon in the Pacific Ocean near the equator of either warmer than normal or cooler than normal water.
According to NOAA, we are still in a neutral state as we transition from last year's El Niño to the anticipated La Niña, but temperatures have been cooling rapidly in that region of the ocean, signaling that a La Niña may be imminent.
La Niña is favored to emerge in the next two months and is expected to persist through at least February 2025.
During this winter's La Niña event, cold waters in the Pacific will push the polar jet stream over the U.S. northward. This tends to lead to drought in the southern U.S. and wetter weather in both the Pacific Northwest and Midwest regions.
The position of the jet stream also typically leads to warmer than normal weather in the southern U.S. and normal or colder than normal weather in northern areas.
But how certain is this potential of a snowy winter in the Chicago area?
The First Alert Weather team analyzed La Niña events in our area over the last 10 years and found that snowfall between December and February actually averaged slightly lower than normal.
Average winter snowfall (1991-2020) in Chicago: 29.6"
Average winter snowfall during La Niña winter: 28.3"
Climate change may be an explaining factor.
Winter is Chicago's fastest-warming season, with temperatures now 3.5 degrees higher than they averaged in 1990. This means that even as La Niña produces higher precipitation in certain winters, more of it may be falling as rain instead of snow. Chicago used to average 32 days per year with measurable snow -- now, the city averages 27 days.
Final winter outlooks are released in mid-November. For updates, stay with the CBS News Chicago First Alert Weather team.
- Winter 2011/2012 snow: 19.5"
- Winter 2017/2018 snow: 30.2"
- Winter 2020/2021 snow: 46.3"
- Winter 2021/2022 snow: 28.6"
- Winter 2022/2023 snow: 16.8"