Neither groundhog saw its shadow, indicating an early spring.

The zoo’s seven bottlenose dolphins will spend the next six weeks getting used to their new and improved digs.

The alignment of sun, earth and moon will plunge the city into darkness, and as long as the maddeningly unpredictable Northeast Ohio weather cooperates, people will view a spectacle that lasts just under four minutes but occurs only three times in a 638-year span above the city.

Advocates say the proposed ordinance aims to combat climate change and reduce the amount of greenhouse gas emissions, while critics believe it would increase cost and risk reliability.

The U.S. National Science Foundation awarded the grant to Current Innovation NFP, a nonprofit “innovation hub” whose mission is to “solve pressing water challenges caused by climate change and pollution.” 

Freshwater mussels can be a river system’s best friend, but they’re missing from long stretches of the Chicago River. Here’s a look at one effort to reintroduce them.

From catching walleye to bringing restoration work out of the dark ages to passage of a groundbreaking tax hike, Arnold Randall reflects on his 13 years as general superintendent of the Forest Preserve District of Cook County.

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.

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

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.

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.

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

“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.

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

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.

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.