Record-shattering cold, heavy snow and howling winds are descending on a broad swath of the U.S., the National Weather Service says. It's the result of one of the coldest arctic air masses to hit the country in recent memory, the agency says, forecasting bitter conditions in areas from the Upper Midwest to many Eastern states.

Warning of a "very dangerous and life-threatening arctic blast," the weather service predicts that the next several days could see "widespread record lows and low maximum temperatures from the Upper Midwest to the Great Lakes and Ohio Valley."

Officials also are warning of horrible travel and road conditions, high temperatures that stay in the single digits and wind chills that dip far below zero.

In Michigan, Gov. Gretchen Whitmer has declared a state of emergency, urging people to limit the time they spend exposed to the elements and to check on the well-being of children, older neighbors and pets. Her office advised people to keep water dripping through vulnerable pipes to prevent them from freezing — and to set the thermostat to the same temperature for night and day.

"Keeping Michiganders safe during this stretch of dangerously cold temperatures is our priority," Whitmer said.

Frigid weather has already started to hit the Dakotas, Minnesota, Wisconsin and Illinois. It is expected to sweep into the Eastern U.S. in coming days, forcing residents and businesses, governments and schools to adapt to intensely low temperatures.

Wisconsin could see wind chill values from minus 30 to minus 50 degrees, Gov. Tony Evers said as he declared a state of emergency in his state Monday afternoon.

"When it gets this cold, nobody should be outside unless it is absolutely imperative for them to be outside," Douglas Brunette, an emergency room doctor at Hennepin Healthcare, told Minnesota Public Radio.

"Stay inside," Brunette said, warning of the heightened risks of frostbite and hypothermia. "Don't challenge nature."

Farther east, in Buffalo, N.Y., the city's public school district canceled classes for Wednesday and Thursday and told school staff to stay home, citing the forecast of "heavy lake effect snow, winds, and extreme cold." Other nearby districts were making similar plans, as member station WBFO reports.

A winter weather advisory went into effect at 4 a.m. Tuesday in Baltimore, where health officials declared a "Code Blue" emergency through Friday morning. "The designation prompts agencies to offer free meals for senior citizens, encourage homeless people to seek shelter and help residents apply for utility bill assistance," The Baltimore Sun reports.

As of Tuesday, more than 1,800 flights had been canceled and more than 8,000 had been delayed.

Federal government workers in the Washington, D.C., area were allowed to leave two hours early, according to the Office of Personnel Management.

In the Southeast, predictions of perilous weather prompted Delta Air Lines to cancel 170 flights out of Atlanta on Tuesday. Member station WABE's Susanna Capelouto says it was a pre-emptive move and that travelers will be allowed to change their flights without a penalty.