A cyclist makes his way along a path beside the Rideau Canal Skate Way in Ottawa on Monday, January 5, 2015. Within the last 24 hours the nation's capital has gone from freezing rain and above zero temperatures into a deep freeze and frostbite warnings.Sean Kilpatrick
Ontario is shivering through a deep freeze with Environment Canada issuing an extreme cold warning for most of the province.
The weather agency says a cold front that passed through southern Ontario early Wednesday brought very cold temperatures and winds resulting in wind chill values near -30 C or lower.
In northern Ontario, the weather agency says the low temperatures combined with moderate winds has produced wind chills near or below -40 C but adds conditions are expected to improve Wednesday as temperatures rise.
An extreme cold weather alert has been issued in Toronto, where Mayor John Tory had asked the city manager to open two 24-hour drop-in warming centres late Tuesday due to concerns about vulnerable people following two deaths believed linked to the cold.
The city's medical officer of health issues the alerts when overnight temperatures are forecast to drop to -15 C or colder.
During extreme cold weather alerts, extra shelter spaces are made available and overnight street outreach is increased in the downtown core to get the homeless in from the cold.