The good times are over for the middle and eastern parts of the country with winter arriving fashionably late — and very loudly — this week, forecasters said Monday.
An arctic air blast that showed up over the weekend was forecast to send temperatures plunging to dangerously low levels overnight Monday into Tuesday.
Minneapolis' low temperature Tuesday morning is expected to drop to 10 degrees below zero, and wind chills all the way down to minus-40 are forecast for parts of the Dakotas and other parts of Minnesota, the National Weather Service said early Monday evening.
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Volunteers of America Michigan added overflow beds Monday night at its shleter in Lansing, where temperatures were already in the single digits.
"You've got to find a spot for everybody, because you can die tonight from exposure," Patrick Patterson, the organization's executive vice president, told NBC station WILX. "That's as simple as it gets. We're just trying to keep people safe tonight."
At Bob Hamilton Plumbing & Heating in Kansas City, Missouri, "the phone has been ringing all day long," owner Bob Hamilton told NBC station KSHB. "It's not something that's going to go away, because the cold is here."
Subfreezing temperatures will stretch all the way to the East Coast, where forecast low temperatures for Tuesday include 13 degrees in Boston, 18 in New York City and 12 in Washington, D.C.
Connecticut Gov. Dannel Malloy activated the state's severe cold weather protocol, mobilizing dozens of state agencies to respond to public safety and social services crises. Baltimore's health commissioner, meanwhile, issued a Code Blue alert opening shelters and the city's homeless services outreach network.
Even a large part of north Florida was under a freeze warning overnight, with Jacksonville expecting a low of 28 degrees, while Raleigh, North Carolina, was expected to hit 16 and Memphis, Tennessee, was predicted to hit 17.
And that's just the windup.
A second, separate system will quickly move in at midweek, this one carrying a lot of atmospheric moisture that means "we'll certainly be anticipating plowable snow in the mid-Atlantic into the Northeast," said Danielle Banks, a meteorologist for The Weather Channel.
The National Weather Service stressed that there's still "uncertainty given the fact that this is several days out," but it said conditions were shaping up for major winter storms in the Washington, D.C., Philadelphia and New York City areas late Friday through Saturday.
"I'm not ready at all," Megan O'Neill, who was shopping for supplies Monday in Lafayette Hill, outside Philadelphia, told NBC Philadelphia. "I would like the 60 degrees to continue for the rest of the winter."
Zach Velivis of Vecchione Tire in Orland, Pennsylvania, urged drivers not to be fooled by the warm, sunny weather ahead of the storm and to get their tires checked soon.
"I would definitely do it now, because in the next two or three days, if the snowstorm is going to happen, we're going to be swamped from the time we open till probably after we close," he told the station.
And significant snow at high tide could cause coastal flooding because of high tides swelled by a full moon, it said, while heavy winds could create blizzard conditions around Washington.
Sleet and freezing rain are expected to cause extremely hazardous driving conditions as far south as Tennessee, with more than an inch of snow possible all the way down to Atlanta.