A polar air mass that’s hardened the Upper Midwest and much of the eastern U.S. in a deep freeze has taken an especially harsh toll on homeless people across the country.

While shelters across the region have extended their hours and made more beds available, outreach workers are on the streets helping the nation's homeless who remain out in the bitter cold.

"We've heard from some of our outreach workers, families are making their way to all-night places like Walmarts or McDonalds and just kind of huddling there and trying to stay warm and then moving on to another place," Liz Kuoppala, who heads the Minnesota Coalition for the Homeless, told Minnesota Public Radio. "But it's really tough to stay alive outside."

Earlier this week, the coldest location in the lower 48 states Monday was Embarrass, Minn., at 36 below, the AP reported. And shelters in the northern part of the state that would normally house 50 were bulging with 70 people seeking refuge. In St. Paul, Deb Holman, an outreach worker, has found people sleeping in the woods with only a sleeping bag or few blankets to brace the elements, Minnesota Public Radio reported.

"I always worry about these guys making it through this cold spell," she told the news outlet. "And then feeling a sense of responsibility to go out there and try to help them, even if it's above and beyond, you know, the call of duty, because you know they're out there. So you have to try to do something."

In Milwaukee, $50,000 has been donated by the United Way of Greater Milwaukee to two area homeless shelters to open more locations for overflow, the AP reports. The temperature in the Midwest capital was just 2 degrees at noon on Wednesday, according to the news outlet.

"We're incredibly relieved," Donna Rongholt-Migan, executive director of the Cathedral Center, a Milwaukee shelter that received $25,000 told the AP. "I was walking my dog last night and I couldn't feel my legs just after walking around the block."

In Detroit, where it was 7 degrees with a wind chill of 10 below zero around noon on Wednesday, warming shelters have opened and extended their hours to meet the rising demand, according to the Detroit News. Authorities have been patrolling the city ready to transport homeless to nearby shelters, Paula Bridges, Wayne County Sheriff's spokeswoman told the news outlet.

"We certainly didn't want anyone left out in the inclement weather, so we had folks check overpasses and areas where the homeless might be," Bridges told the Detroit News. "But, unfortunately, a lot of them feel like they have a prime location, so we have to respect their right not to leave."

For the homeless population in Burlington Vt., finding a place to stay is proving harder than expected.

The state has a “cold weather policy” which allows the homeless to get a free motel room when the weather drops, the Burlington Free Press reports. But in order to secure a room, many motels require a photo I.D., something a number of the homeless do not have, according to the news outlet.

Stefanie Comstock, a Burlington social worker, says she met at least 10 of the people who spent the night in tents after being turned down from motels, she told the Free Press.

Find ways to help locally at the National Coalition for the Homeless, United Way, Red Cross and Salvation Army.

MANHATTAN, UNITED STATES: An unidentified homeless man takes shelter from the cold weather on Manhattan's Fifth Avenue outside the Bergdorf Goodman department store 05 February 1996 in New York. Across most of the eastern United States, record low temperatures have closed schools, businesses, roads and airports. (Photo credit should read JON LEVY/AFP/Getty Images)

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