Brutally cold temperatures impacting much of the U.S.

In other parts of the U.S., if the problem wasn’t snow and wind, it was water: Record high tides hit the Northeast, flooding some homes in Maine and New Hampshire.

The coastal Northeast was pounded by 1 to 2 inches of rain in the morning, and a storm surge amplified what was already the month’s highest tide, National Weather Service meteorologist Michael Cempa said.

In Portland, Maine, a gauge recorded a 14.57-foot difference between high and average low tide, topping a prior record of 14.17 feet set in 1978.

Photos from Joshua Smick of Hampton, New Hampshire, showed rushing water on roads in the coastal town.

“I’m 42 years old, and I don’t recall ever seeing anything like this in New England before," Smick told NBC News.

KANSAS CITY, Mo. — With frosty suites, a cracked helmet, a frozen mustache, it's hardly surprising that the Chiefs' 26-7 win over the Dolphins ranks as the fourth-coldest game in NFL history.

And while minus 8 degrees (and minus 25 wind chill) was plenty cold for fans at Arrowhead Stadium tonight, the all-time coldest NFL game record was never at risk. That belongs to the 1967 NFL championship game: It was minus 13 when the Packers beat the Cowboys at Lambeau Field in the Ice Bowl. Wind made that day feel like minus 48 degrees

So until Kansas City knows who and where the Chiefs play next, Wednesday is the focus. That's the next time temps will climb above freezing.

As of Saturday night, 45 million people in the United States were under a winter weather advisory, according to the National Weather Service.

A wind chill warning affected more than 30 million and a wind chill advisory was in place for another 63 million. A winter storm warning was in effect for 18 million.

Cities along the Great Lakes and in the region continue to be affected by major snowstorms tonight and into tomorrow, with warnings from the National Weather Service that an additional 1-2 feet of snow will be dumped on some parts of the area through Monday.

The Weather Service said whiteout conditions are expected in the lake-effect snow bands as the arrival of cold air generates more heavy snow. Parts of western and southern New York State will see 12-24 more inches through Monday and parts of Michigan are expecting more than a foot.

Chicago has already seen 6.7 inches of snow, with other parts of Illinois recording more than 13 inches. The area is expecting another 1-2 inches tonight.

Milwaukee has 10.1 inches of snow on the ground and nearby Waukesha, Wisconsin, is in 14-16 inches territory.

Buffalo is expecting 8-12 inches of snow tonight and into Sunday before the Monday dump. Detroit only has a few inches right now, but will likely see more as the storm continues.

By 6 a.m., the Twin Cities were reporting around 2 inches of snowfall, but other areas of the state further south and areas near the border in Wisconsin are already seeing more than a foot.

New York City could see snow squalls in addition to strong winds and cold temperatures tomorrow, the New York City Emergency Management Department said in a weather alert issued for Sunday.

An Arctic cold front will grace the area Sunday afternoon, bringing the potential for snow squalls, leading to low visibility, gusty winds and short periods of moderate to heavy snow.

Squalls often last less than 30 minutes but can be intense, like a "mini-blizzard," the weather alert said. City-dwellers should be prepared for a half inch of snow on the ground and 40-45 mph winds from 12 p.m. to 3 p.m.

Roads can get slippery during snow squalls, but because of mild temperatures in New York City, they shouldn't get icy.  

New York City Mayor Eric Adams said the city will be working to salt streets but asked New Yorkers to stay off the roads if there is a snow squall warning in their neighborhood.

KANSAS CITY, Mo. — The Chiefs may be heading into the locker room with the lead — they're up 16-7 — but there's no doubt that Miami is sitting way prettier, the city of Miami that is.

It's 69 degrees in Miami, downright steamy when you compare it to what it feels like in Kansas City: 23 below.

That's weather cold enough to freeze your mustache, just ask Chiefs Coach Andy Reid.

Despite patches of ice covering GEHA field at Arrowhead Stadium, the conditions in Kansas City appear worse than they actually are, with players telling NBC Sports' Kaylee Hartung that they were having no trouble during warm ups.

That's thanks to Arrowhead's underground heating system, comprised of boilers pumping heat into thousands of feet of pipes, which acts "like a radiator to warm the grass and roots" to keep the field from totally freezing over, Hartung said.

Each player has a different strategy — the Dolphins’ Raheem Mostert is wearing a sleeveless wetsuit, Hartung reported. And each team's sideline has heated benches and heaters blowing air to keep players — like Tyreek Hill, who said he is wearing short sleeves because he didn't want to look "soft" — and coaches warm.

Watch the full report on NBC Sports.

Nebraska Gov. Jim Pillen announced a state of emergency, citing “very dangerous conditions.” Up to 2 feet of snow fell in some areas over the past week, and wind chills were well below zero.

“This event is not going away tonight. It’s not going away tomorrow,” Pillen said at a news conference “It’s going to take a number of days.”

About 1,700 miles of Nebraska highways were closed. State police assisted over 400 stranded motorists, said Col. John A. Bolduc, head of the Nebraska State Patrol.