Wiktionary
n. A warming center is a type of emergency shelter that operates when temperatures in an area become dangerously low, serving stranded travelers, displaced renters and homeowners, and unsheltered homeless people.
Wikipedia
A warming center is a short-term emergency shelter that operates when temperatures or a combination of precipitation, wind chill, wind and temperature become dangerously inclement. Their paramount purpose is the prevention of death and injury from exposure to the elements. This may include acute trauma from falling objects such as trees, or injury to extremities due to frostbite. A more prevalent emergency which warming centers seek to prevent is hypothermia, the risk for which is aggravated by factors such as age, alcohol consumption, and homelessness.