The Doomsday Clock was set at 90 seconds to midnight in 2023 and this year. (Anna Moneymaker / Getty Images / FILE)

On Tuesday, the clock was again set at 90 seconds to midnight — the closest to the hour it has ever been, according to the Bulletin of the Atomic Scientists, which created the clock in 1947.

Adult spotted lanternfly. (U.S. Department of Agriculture)

Experts said the pest’s eggs, which will hatch in spring, are able to withstand the recent arctic blast.

(National Weather Service)

Sundogs form when waves of sunlight pass through ice crystals suspended in clouds. They resemble rainbows or halos, or can even resemble a second sun.

Snow blankets Chicago, Jan. 12, 2024. (Patty Wetli / WTTW News)
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CPS announced classes will be in session for all students Wednesday as the frigid temperatures the city has seen this week have begun to dissipate.

(Pixabay)

The Chicago region remains under a wind chill warning Tuesday morning as bitterly cold temperatures persist.

A resident walks down a snowy sidewalk in the North Park area on Dec. 22, 2022. (WTTW News)
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“We have been carefully monitoring the forecast over the past 24 hours, and have determined that given frigid temperatures predicted for tomorrow, and a Wind Chill Warning from the National Weather Service that wind chills that could reach -30 degrees, it will be unsafe for staff and students to travel to school,” the school district said in a statement.

Snow blankets Chicago, Jan. 12, 2024. (Patty Wetli / WTTW News)

The first of two rounds of snow made for a snowy morning commute Friday, with a second round set to hit overnight into Saturday. 

Friday’s afternoon commute could be messy in the Chicago region. (Patty Wetli / WTTW News)

The National Weather Service has issued a winter storm warning for Chicago and the surrounding region, in effect from 3 a.m. Friday through noon on Saturday.

(Patty Wetli / WTTW News)

The National Weather Service is still refining its forecast in terms of snow totals, but is certain that a storm system and arctic blast will hit Chicago this weekend.

Whirl, an Amur tiger at Brookfield Zoo, jumps up to reach for a bone in a Christmas tree that was hung in her habitat for enrichment. (Jim Schulz / CZS-Brookfield Zoo)

Trees from Brookfield Zoo’s Holiday Magic display were repurposed as enrichment activities for several animals. 

(WTTW News)
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Chicago Public Schools was among 67 winners of the U.S. Environmental Protection Agency’s first Clean School Bus Program.

Snow falls on Chicago's North Side, Jan. 9, 2024. (Patty Wetli / WTTW News)

The second of two rounds of storms is still expected to dump significant amounts of snow in the northwest portions of the greater metro area Tuesday afternoon and early evening, according to the weather service.

Using a glass or stainless steel container is a safer way to consume water, experts say. (Clara Margais / dpa / picture alliance / Getty Images)
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Nanoplastics are so teeny they can migrate through the tissues of the digestive tract or lungs into the bloodstream, distributing potentially harmful synthetic chemicals throughout the body and into cells, experts say.

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Every winter, Chicago stands divided around a practice commonly known as “dibs” – when car owners use janky household objects to reserve their precious shoveled-out parking spaces. So how did it begin? 

(WTTW News)

Parts of the Chicago region could get socked with upwards of 8 inches of snow while areas closest to the lake could see just an inch or two, forecasters said.

(Courtesy Illinois Tourism Office)

Illinois boasts the largest population of wintering bald eagles outside of Alaska. They’re attracted to our not-quite-frozen waterways.