Wake County schools have a late start on Tuesday morning, but families shouldn’t count on more delays this week as freezing temperatures continue.

“I don’t expect any more delays, but I think it depends on what the weather does,” said Wake schools spokeswoman Lisa Luten. “It’s usually just this first day back because the buses have been in idle for so long.”

Wake opened schools Tuesday on a two-hour delay “due to the likely effects of extreme temperatures on buses left idle during winter break.” School buses hadn’t run since winter break began Dec. 22.

As of 9 a.m. Tuesday, 81 buses hadn’t started initially, Luten said. But 90 percent of those buses were fixed and running, and Wake used spare buses to fill in for those those that need repairs.

The Wake County school system announces schedule changes on Twitter and school websites and through a phone call, text and email to parents. Here’s a guide on how to get those updates or change your preferences.

Students should bundle up as they head to bus stops this week. Temperatures are expected to be in the teens most mornings, and temperatures will only get above freezing on Wednesday afternoon before dipping back down. The winds will make it feel even colder: The National Weather Service issued a wind chill advisory Tuesday for counties from Winston-Salem to the coast.

Other school districts were also prepared for bus issues Tuesday morning. In addition to Wake, Durham, Orange, Chatham and Harnett schools and Chapel Hill-Carrboro City Schools were all on a two-hour delay Tuesday. Durham school officials said they needed extra time to ensure that both the school buses and the heating systems “are working smoothly after winter break.”