After a relatively mild January, much of Eastern Canada, including Toronto–is set to be hit with frigid temperatures this week.

The polar vortex bringing in winds could hit Toronto with the coldest temperatures the city has seen in years, according to The Weather Network. 

The City of Toronto issued an extreme cold weather alert Monday morning. 

Toronto’s Medical Officer of Health issues an extreme cold weather alert when Environment Canada forecasts a temperature of -15°C or colder, or a wind chill of -20°C or colder.

The frigid temperatures are expected to be short-lived, but will pack quite a punch, according to The Weather Network. 

It says southern Ontario won’t see daytime highs reach above the freezing mark until around Feb. 8.

The most likely scenario for temperatures early Saturday morning in the GTA will fall below -20°C in areas away from the lake, and in eastern Ontario temperatures are set to plunge below -30°C.

In anticipation of the chilly weather, Toronto announced Monday it would be opening a fourth warming centre at Cecil Community Centre. 

All four warming centres in the city will be open Tuesday by 7 p.m. to give those who are vulnerable and may be experiencing homelessness a safe, warm indoor place to rest and access snacks, washroom facilities and referrals to emergency shelter. according to the city. 

The other three warming centres are located at Scarborough Civic Centre, Metro Hall, and Mitchell Field Community Centre.