ST. PAUL — Gov. Mark Dayton has canceled all public school classes statewide for Monday in anticipation of dangerously cold temperatures, the first time a Minnesota governor has taken that step in 17 years.

“The safety of Minnesota’s schoolchildren must be our first priority,” Dayton said in a statement Friday.

The National Weather Service is forecasting the lowest temperatures in at least a decade Monday, with air temperatures that could reach as low as minus 30 and high temperatures only reaching the minus teens.

“I encourage Minnesotans of all ages to exercise caution in these extreme weather conditions,” Dayton said.

It’s the first time a Minnesota governor has closed schools in response to cold weather since January 16, 1997. According to the State Climatology Office, former Gov. Arne Carlson called off classes that day as the wind chill fell to minus 32 in the Twin Cities.

Carlson also closed schools statewide on Feb. 2, 1996. That’s the day that a state record low was set, according to the Climatology Office, when the air temperature plunged to minus 60 near the northern Minnesota town of Tower. Carlson first closed schools on Jan. 18, 1994, as temperatures hit 26 below zero in the Twin Cities.

School administrators in Rochester had already canceled classes for Monday. Dayton’s office said he made the decision Friday in order to give school administrators, teachers and parents time to plan for the closures. The state Department of Education was coordinating with school districts to make sure the public is adequately notified about the school closings.

Most public school students were set to return to school for the first time Monday after a two-week winter break.

Dayton’s education commissioner, Brenda Cassellius, didn’t rule out the possibility of another day of canceled classes on Tuesday. However, she said it was likely that decision would be left to individual school administrators.

Dayton’s decision applies only to students. Cassellius said district must individually decide whether teachers and other employees report to work.

Minnesota law gives the governor the power to “authorize the commissioner of education to alter school schedules, curtail school activities or order school closed,” according to the language of the statute. Cassellius said the principal reason for the decision is that officials don’t want kids waiting outside for the bus or walking to school in temperatures that can cause frostbite in as little as five to 10 minutes.

“It could be quite dangerous for so many of our children,” Cassellius said. She urged parents to keep children inside on Monday.

The order also applies to public charter schools, but not private schools. However, Cassellius pointed out that many Minnesota private schools coordinate student transportation with public districts, and that school buses won’t be running Monday.

Police said subzero cold had already contributed to the death of a 79-year-old New Ulm man. William Harry Lee was found unresponsive in his backyard Thursday night. Police said he apparently fell, and the Brown County coroner ruled the death accidental. The temperature was 18 below when officers arrived, KTOE-AM reported.

State officials urge Minnesotans to be prepared for extreme low temperatures by having a plan in case of power or furnace outages or other unforeseen circumstances.

It’s not just schools that are closing Monday. Apple Valley’s Minnesota Zoo, which has a number of outdoor exhibits, announced it would shut down for the day. Director Lee C. Ehmke said the decision was made to encourage people to stay home.