Boston Mayor Marty Walsh and about 300 volunteers were out in the cold Wednesday night to count the number of homeless living on the streets of Boston.

  Walsh approached a man, Edward, on Washington Street just after 9 p.m., wearing earmuffs and a backpack. He had several green plastic bags at his feet. They spoke briefly, and the mayor encouraged him to check into a shelter as the temperature dropped to 14 degrees.

“I have been in some places and run into problems," Edward told Walsh. "I guess you’d say chemistry. So I just try to stay away from problems."

Jim Greene, director of the Boston Emergency Shelter Commission, joined Walsh to walk Downtown Crossing, stopping to meet homeless men and women and encourage them to accept a ride to a shelter. One man said he avoids shelters because he disagrees with their rules.

It was so cold it was difficult to find homeless people. But volunteers planned to stay out until 4 a.m. They divided into groups, walking every street in the city, counting people in shelters, and in transitional, youth, and veterans housing. The most recent homeless census, in 2013, found 7,255 individuals, an increase of 3.8 percent over the previous year. This year, with the closure of Boston Harbor’s Long Island shelters and treatment facilities, that number could be higher, but the final tally won't be released for a few weeks.