2024 forecast to close with warmer temperatures, slight rain

Unseasonably warmer temperatures are expected to continue in Chicago through New Year's Eve, ending 2024 with what could be the city's warmest year on record.

Sunday saw a high near 44 degrees with light rain and winds of around 15 mph, according to the National Weather Service. A dense fog is also expected to move in overnight and last through Monday morning.

The balmy temperatures will likely continue through the first half of the week, with highs near 47 degrees Monday and 42 on Tuesday, according to the weather service.

Monday should be cloudy with little chance of rain. On Tuesday, the chance of rain is 30% to 80%, mostly south of I-80, according to the weather service.

Temperatures will drop Wednesday to a high near 32 degrees, kicking off 2025 with the return of cooler, more seasonable weather.

But the warmer temperatures leading up to the new year could establish 2024 as Chicago’s warmest year on record, breaking the previous record set in 2012, according to the weather service.

Based on preliminary data, Chicago's average temperature for 2024 is on track to be between 54.8 and 55 degrees, beating the previous benchmark of 54.5 degrees in 2012, the weather service said.

But official numbers for 2024 won't be released until or just after New Year's Day.

Gino Izzi, a meteorologist with the National Weather Service, said climate change and a fall drought are the reasons for the higher temps this year. Air is easier to heat and cool than water, so less moisture means bigger jumps in temperature throughout the day.

“It’s a very unique situation,” Izzi said. “When conditions are really dry, temperatures more quickly fluctuate. … That allowed temperature swings to be more drastic.”

Additionally, five months of 2024 were in the top 10 warmest on record in Chicago, according to the weather service. February set a new record with an average of 39.5 degrees — beating the previous record of 39 degrees set in 1882 — and September was the second-warmest on record, averaging 70.6 degrees, one degree shy of the 1931 record.

Rockford is also set to have one of its top five warmest years on record, ending the year with an average between 52 and 53.1 degrees.

Looking ahead into January, Chicago could see a month of "closer to or below-average temperatures," Izzi said. And snow may spring up near the end of the month.

“There will still be cold periods mixed in,” Izzi said. “But on the whole, climate change is making it easier for warmer conditions to happen more often.”

Contributing: Violet Miller