The City of Toronto has issued its ninth extreme cold weather alert of 2016, with temperatures expected to dip overnight.

The city's Medical Officer of Health David McKeown issued the alert Wednesday morning, although it was only -3 C at the time.

McKeown sent out the alert based on the forecast, which predicts the temperature will drop to -15 C late Wednesday night. With the wind chill, it will feel closer to -20 C, according to Environment Canada.

Nine alerts have been issued so far in the winter of 2015-16. Over the last 10 years, an average of 18 extreme cold weather alerts have been issued each year in Toronto.

The city issues an extreme cold weather alert when Environment Canada forecasts a low of -15 C or colder, or the wind chill is expected to be below -20. The alerts may also be issued at warmer temperatures when other factors could impact health, including if there have been several days of cold weather or there is precipitation.

During extremely cold weather, those in the affected area are warned that they can be at risk of frostbite, frostnip and hypothermia. Residents are advised to check on vulnerable friends, neighbours and family members during the alerts.

McKeown's alert warned that the people most at risk of cold-related illness are those who work outdoors, have pre-existing heart conditions or respiratory problems, infants and the homeless.

During the alerts, the city offers additional services for homeless people, including offering TTC tokens, increased street outreach and directions to shelters to relax restrictions. Two 24-hour drop-in centres are also available. 

While the alert is in effect, the city recommends:

  • Dressing in layers, covering all exposed skin
  • Wearing a hat, mittens or gloves and warm boots
  • Staying dry
  • Choosing wool or synthetic fabrics instead of cotton
  • Avoiding alcohol
  • Rescheduling outdoor activities