Arctic temperatures hitting cities like New York, Chicago and Denver are endangering newly arrived migrants and complicating cities' efforts to manage limited shelter space.

Why it matters: It is another crisis point for strained official and non-government networks trying to care for migrants across the country.

• It is also another trial for the thousands of people who have taken perilous journeys from their home countries — often with warmer climates — to seek a better life in the U.S.

Be smart: Border crossings used to decline or stay low during the winter months — ticking up as the weather warmed. This year, December reportedly set a new record for illegal border crossings.

Driving the news: Chicago has temporarily suspended a new 60-day shelter limit because of subzero temperatures.

• Evictions had been scheduled to begin this week. But the policy won't go into effect until Monday when temperatures are supposed to lift into the 30s. (Its limits include exceptions for extreme weather and sickness.)
• Denver also has not been enforcing its 14-day shelter limit for migrant adults due to temperatures. Supplemental cold weather shelters are set to be open through Jan. 20.

In New York City, 350 migrant families and 23,000 migrant adults have maxed out new shelter limits, according to city statistics provided to Axios.

• A spokesperson for NYC Mayor Eric Adams said no family that applies to remain in a shelter longer has been rejected.
• Just a quarter of adult migrants have reapplied for shelter space because most find housing alternatives, said the spokesperson.
• "[A]s the temperatures continue to drop in cities across the U.S., it's imperative, now more than ever, that the federal government provide meaningful support to municipalities," Kayla Mamelak, deputy press secretary for Mayor Eric Adams, told Axios.

What we're hearing: It's not just in cities. Border areas are also preparing for the cold.

• "That is always a concern for us ... trying to give [migrants] the proper clothing that they need, but also making them aware of how severe the weather gets in those cities," says Sister Norma Pimentel, who works in migrant care as executive director of Catholic Charities in the Rio Grande Valley.
• Her shelter's staff members are confirming people have sponsors willing to take them in before they let them on Texas-sponsored buses.
• "We don't want to participate in those state buses unless these families are really responsible for themselves and they don't end up being a major problem for those cities — and risking their lives," she added.

The bottom line: Thousands of migrants and asylum seekers are continuing to make their way across the border and into major U.S. cities.

• Historically, most migrants attempting to cross the border have had family or friends already in the U.S.
• That has increasingly not been the case — especially with new Venezuelan populations — which has added to the challenge.

Editor's note: This story has been updated to reflect that Denver has extended its cold-weather shelters from Jan. 19 to 20.