As the temperature drops in the Lower Mainland, Vancouver's emergency shelters will be open again tonight to provide a safe space for the homeless.

The city activated its extreme weather alert this weekend, meaning more shelter beds open up throughout the city’s downtown core.

"When it gets to be that cold, the message that we want to get out to be people is that it's dangerous," said Irene Jackson, the coordinator of the Extreme Weather Response Program.

"It really poses a health and safety risk for people who are sleeping outside. And we want to get the message that there are shelter spaces available, there are mats available, and to please come inside."

Vancouver's Union Gospel Mission says even a temperature of zero overnight can be dangerous for someone sleeping outside. (CBC)

The alert was first activated on Saturday, and Jackson says no one was turned away.

Keela Keeping with the Union Gospel Mission says the emergency shelters help take the pressure off.

“When the HEAT shelters are open, that takes a bit of pressure off us and we aren't generally at capacity, which is fantastic, because we want to make sure that when someone comes inside, they have somewhere to sleep, they have somewhere to go,” she said.

Keeping says even a temperature of zero overnight can be dangerous for someone sleeping outside.

She says the emergency shelters seem to be meeting the need right now, but adds the real problem is finding long-term housing.

The following sites will be open overnight Sunday:

• St. Mark’s Extreme Weather Shelter, 1805 Larch Street. Up to 25 people. Opens at 9:30 p.m. Intake closes at 11:00 p.m. .
• The Gathering Place, 609 Helmcken Street. Up to 40 people. Opens at midnight
• Union Gospel Mission, 601 East Hastings Street. Up to 20 spaces for men if the shelter's regular 72 beds are full. Opens at 9 p.m.
• Catholic Charities, 828 Cambie Street. Up to 20 men.
• Covenant House, 575 Drake Street. Up to 12 youths. Opens at 9 p.m.