Environment Canada has issued a wind chill warning for London-Middlesex and nearby counties and there are blowing snow warnings in effect further north.
Areas from Windsor through to Toronto and everywhere in between are expected to see extremely cold temperatures.
The weather agency says a cold arctic airmass will remain in the area Thursday night, which could produce temperatures as low as -20 C. With the wind chill temperatures will feel more like -35 C.
In Huron, Perth, Grey, Bruce and northern Wellington County a blowing snow warning has also been issued.
Environment Canada says very strong southwest winds of 40 to 60 kilometres/hour with gusts to 80 are forecast to begin Friday afternoon ahead of an arctic low pressure system expected on Saturday.
The winds, combined with falling snow are expected to result in widespread blowing snow, lowering visibilities to 500 metres or less through Friday night.
Environment Canada is asking the public to exercise caution when heading outside in the cold and motorists are advised to exercise caution as visibilities are expected to be near zero at times.
