DETROIT (AP) — The calendar says it’s still spring, but for parts of the Great Lakes region, hot, summerlike temperatures already have arrived, forcing some schools to close or shift students to remote learning.

Detroit Public Schools Community District began closing its more than 100 schools three hours earlier Thursday and will do the same Friday as temperatures in the Motor City were expected to soar to near 90 both days.

Indoor afterschool activities also are canceled, according to the district.

Last June 1, Detroit’s high was a cooler 82 degrees. The city’s all-time high for the date was 97 degrees in 1934.

In western Michigan, Grand Rapids Public Schools canceled all classes and after-school activities Thursday and Friday due to the extreme heat. Temperatures in some school buildings Wednesday were too warm, Superintendent Leadriane Roby said in a message on the district’s website.

“That not only makes the learning environment a challenge, but it also raises a safety concern,” Roby said.

Forty public schools in Pittsburgh with insufficient air conditioning went to remote learning Thursday and Friday under the district’s extreme heat protocol, with “grab and go” meal service provided at 14 locations.

In Philadelphia, 90 of the district’s schools plan to dismiss students two hours early on Friday. Philadelphia is working to have all of its schools air-conditioned in the coming four years. Summer vacation is nearly two weeks away for city schools.

Some relief is coming, but that’s still a few days away, according to Steven Freitag, a national weather service meteorologist.

“It’s just a large stagnant pattern where we’re controlled by the high-pressure ridge over the Great Lakes region and eastern Canada,” Freitag said. “It’s kind of a dryer heat; nothing terribly unusual about it. And we haven’t had much rain. The ground is dry as well. We’re going to have a little colder air coming in next week.”

Detroit, Columbus, Ohio, Pittsburgh and some other cities were expected to see highs near to just above 90 degrees through Saturday. Daily highs in Indianapolis could reach 90 or above through Monday, according to the National Weather Service.