An extreme cold weather alert is now in effect in the city of Toronto.

Morning temperatures in Toronto were seasonable with a brisk breeze and a high of 3 C, but the evening is expected to bring in more clouds and cooler winds.

Cold Toronto

The temperature is expected to dip down to -12 C on Friday evening.

An extreme cold weather alert is issued by the medical officer of health when Environment and Climate Change Canada forecasts a temperature of -15 C or colder, or a wind chill of -20 C or colder.

“Exposure to cold weather can be harmful to your health,” city officials said in a news release issued on Friday morning. “Hypothermia occurs when the body’s core temperature drops below 35 C and can have severe consequences, including organ failure and death.”

“Frostbite can also occur in cold weather when skin freezes and, in severe cases, can lead to amputation when deeper tissues freeze.”

Officials said Torontonians should look out for people who are most “at risk of cold-related illness.”

“Those most at risk of cold-related illness are people experiencing homelessness or those under-housed, those who work outdoors, people with a pre-existing heart condition or respiratory illness, elderly people, infants and young children. People with heart problems can experience worsening of their condition up to several days after cold weather occurs.”

Anyone who sees a vulnerable person in the city who requires assistance is asked to contact 311 and 911 in emergency situations.

A warming centre opens at Metro Hall by 7 p.m. the day an extreme cold weather alert is activated in the city and remains open until noon the day the alert ends.

The alert remains in effect until further notice, officials said.

The cooler temperatures are not expected to last long as a high of -3 C is expected for Saturday and then a high of 1 C is expected for Sunday.