DC maintains a list of shelters for the homeless. Information on availability at any time can be obtained by calling the Shelter Hotline: 202-399-7093
Between November 1 and March 31, when the temperature or Wind Chill is 32 or below, the District of Columbia issues a Hypothermia Alert. On Hypothermia Alert Day, the District is obligated by law to make shelter available. On those days, your call to the Shelter Hotline should result in the dispatch of a van to take the person from the street to an emergency shelter (or to a hospital if needed). The van is equipped with items such as water, blankets, gloves and jackets.
Shelter locations are listed here.