Remember January's record-setting warm weather? That's changing real quick in February.

The City of Toronto has declared an extreme cold weather alert on Friday as the frigid air rolls in.

The temperature is set to plunge to –17 C overnight (–25 with the wind chill), and Saturday's high will only reach –8 C, according to Environment Canada.

At least it's supposed to be sunny.

It's set to warm up by Sunday, when the high will reach –1 C, and by next week the daytime temperatures will be back around the freezing mark.

During the extreme cold weather alert, the city opens emergency warming centres and urges anyone who sees vulnerable people out on the street to contact 311.

