Cities across the Midwest and Northeast are gearing up to aid their homeless populations this week as a bitter blast of arctic air pushes eastward.
Many cities use "Code Blue" as the designation for emergency services to reach the homeless during times of extreme cold weather.
It will be the coldest air since last winter, AccuWeather.com Meteorologist Brian Lada said.
AccuWeather RealFeel® temperatures are expected to fall as low as -30 F in some areas of the country, setting the stage for dangerous conditions for the homeless and those others vulnerable to the cold.
Homelessness declined 2 percent, or by 13,344 people, between 2013 and 2014 in the United States, according to the 2014 Annual Homeless Assessment Report to Congress.
However, more than 578,000 people were homeless on a given night in January 2014, the most recent analysis by the U.S. Department of Housing and Urban Development showed.
Nearly 136,000 of those homeless people were children under the age of 18, the report stated.
The New York City Department of Homeless Services said its Code Blue calls for increased street outreach efforts - doubling the number of vans in the field and enabling teams to check on individuals more frequently.
When Code Blue is in effect, homeless individuals may also access any of the agency's adult facilities, including shelters and drop-in centers, without going through the usual intake process, the department said.
"New York City should escape the worst of the arctic blast but will still experience temperatures 10 to 20 degrees below normal for early January," Lada said. "This cold should fall short of reaching record territory but will still make for a few frigid days around the middle of the week."
The Midwest is expected to experience brutally cold weather this week, Lada said.
"The coldest air by far will focus on the northern Plains, which includes Minneapolis. This will not be the first time this season that the city drops below the zero-degree mark, but temperatures are expected to drop below zero F each night through Friday," Lada said.
"The high temperatures in Chicago on Wednesday could stay below zero all day. That paired with a frigid wind will keep AccuWeather.com RealFeel® temperatures in the -20 F to -30 F range," he said.
The Chicago Department of Family and Support Services said its effort includes coordinating warming centers, monitoring availability of overnight shelter beds, providing transportation to warming centers and overnight shelters and conducting outreach to homeless people on the street.
About 139,000 Chicagoans were homeless during the 2013-14 school year, a 19.4 percent increase from 2012-13, an August 2014 analysis by Chicago Coalition for the Homeless estimated.
"Temperatures across the region should begin to moderate by the end of the week. However, a glancing blow by another shot of frigid arctic air should keep temperatures below normal through the weekend," Lada said.