Chicago winters keep getting warmer

The winter of 2022–23 has been our 14th-warmest on record, with average temperatures from December through February of 31.7°F — that's 7.6° warmer than those of winter 1970.

• That's according to a new analysis of National Oceanic and Atmospheric Administration numbers from Climate Central, a nonpartisan research and communications group.

Why it matters: Warm winters can exacerbate drought (because there's less snowmelt in the spring), wreak havoc on crops and gardens, and spell disaster for towns built around skiing, snowboarding and similar pursuits.

The big picture: Winter is the fastest-warming season for much of the continental U.S.

• About 80% of the country now has at least seven more winter days with above-normal temperatures compared with 1970, per Climate Central.
• Seasonal snowfall is declining in many cities — though heavy snowstorms can still happen when temperatures are cold enough.
• Precipitation extremes are occurring more frequently and getting more intense, which can lead to feast or famine snowfall.

Driving the news: Not only are winters warming overall, but cold snaps are becoming less severe and shorter in duration, the latest research shows.

• That's partly because the Arctic is warming at three to four times the rate of the rest of the world.
• In other words, our global refrigerator is warming up, making it harder to get record-breaking cold for days on end when weather patterns transport Arctic air southward.

Zoom out: This winter was especially mild across areas east of the Mississippi River. But across the West, it was colder than average. This is reflected in the balance of daily record highs to daily record lows.

• Preliminary NOAA data processed by Climate Central shows there have been 4,857 daily record highs set or tied in the Lower 48 states this winter, and 4,421 daily record lows set or tied.
• A combination of La Niña, a strong polar vortex and a stubborn area of high pressure in the far western Atlantic Ocean favored a weather pattern that kept the East Coast on the warm side of winter storms, delivering snow across the Great Lakes northward into Ontario and Quebec.

The bottom line: Over the coming years, most of us can expect to feel climate change's effects most acutely during the winter months.