An extreme cold weather alert has been issued by Toronto’s medical officer of health as temperatures are expected to feel like -25 C by Saturday morning.

The alert is in effect until further notice, a Friday morning news release said.

According to Alyssa Young, a meteorologist with Environment Canada, roughly three centimetres of snow fell on the city from late Thursday evening into early Friday morning. The bulk of the snowfall occurred earlier in the day, Young said.

The snow will continue throughout Friday and will end in the afternoon. There will be strong winds of 15 km/h gusting to 50 km/h, with temperatures steady around -5 C — although with wind chill it will feel closer to -14 C.

As of 5 a.m., 6.34 per cent of departures and 8.78 per cent of arrivals were cancelled at Pearson Airport. “Snow may cause delays and cancellations today,” the agency tweeted. “If you’re flying, please check your flight status with your airline.”

Early Friday morning the TTC was met with delays on Line 1 due to a signal problem, including a yet-to-be-resolved 15-minute delay southbound from Sheppard-Yonge to Bloor-Yonge station.

The outlook for the weekend is shaping up to be relatively similar. On Saturday, Environment Canada is calling for winds of up to 15 km/h and a high of -8 C. With wind chill, it will feel closer to -25 C in the morning and -11 C in the afternoon.

It will be cloudy on Sunday with a 30 per cent chance of flurries in the morning and more snow expected in the evening. The high will be -1 C — temperatures will dip down to a low of -2 C at night.

Ilya Bañares is a breaking news reporter, working out of the Star’s radio room in Toronto. Follow him on Twitter: @ilyaoverseas