The GTA is plunging into a deep freeze as a blast of arctic air sweeps into the region, dropping temperatures to as cold as -30 C with the windchill.
The cold conditions will stick around until the weekend - but even then it's only warming up to - 5C without the windchill.
The city and several other communities have issued extreme cold weather alerts, prompting extra services to assist the homeless.
Environment Canada says "extreme caution" is advised for anyone going outdoors because exposed skin may freeze in just a couple of minutes.
With files from The Canadian Press.
