Yet another extreme cold weather alert has been issued for the City of Toronto ahead of frigid overnight temperatures.

The city's medical officer of health issued the alert on Wednesday morning.

Environment Canada is forecasting a high of 0 C today, however the weather agency says temperatures will plunge to – 18 C overnight and feel closer to – 27 with the wind chill factored in.

Highs of – 7 C and -5 C are then called for on Thursday and Friday before the temperature warms up to sit around the freezing mark this weekend.

During an extreme cold weather alert, additional services are activated for the homeless including the addition of extra shelter spaces, increased street outreach and the opening of two 24-hour warming centres.

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