Montreal Mayor Denis Coderre says he's prepared to review the temperature at which the city's warming shelters must open.

The city has two warming centres, which are supposed to offer temporary shelter when the windchill makes it feel as cold as –27 C at night.

In early January, one of those centres — the St. Michael's Mission — failed to open its doors on a night when it felt like –28 C with the windchill because they had "misinterpreted the forecast," the city said at the time.

The mayor's willingness to review the minimum temperature follows a petition that's calling for warming shelters to open when the windchill makes it feel like –15 C.

As of Wednesday, more than 3,000 people had signed petition organized by the groups Solidarité dans la rue and SOS Itinérance.

Coderre said any reassessment of the minimum temperature will need to involve a number of factors.

"We have to be scientific and consult with Public Health. And we must exercise judgment and flexibility," Coderre said.

The warming shelters add to the city's network of options for homeless citizens when the temperature drops. Among their users are people with animals and those who don't want to stay at a shelter where they aren't allowed to leave at will.

"We must send the message that no one is left behind in Montreal," Coderre said.

If revising the temperature at which the warming shelters must open requires more funding from the city, the funds will be made available, Coderre said.