A spell of frigid air spilling into Ontario will send temperatures tumbling well below seasonal heading into the weekend. We’ll see lows dip into the 20s below zero by Saturday morning, which could lead to a risk for frostbite and hypothermia. More on what to expect this weekend and beyond, below.

Clear skies and bright afternoon sunshine won’t do much to take away the sting of the cold air across Ontario tonight into Saturday.

Goose bump inducing maps as extreme cold warnings are in place for southern Ontario. Also, the city of Toronto has issued an extreme cold weather alert, which helps open warming centres. #staywarm #toronto @weathernetwork pic.twitter.com/Yl2A7fk953

Goose bump inducing maps as extreme cold warnings are in place for southern Ontario. Also, the city of Toronto has issued an extreme cold weather alert, which helps open warming centres. Nicole Karkic on Twitter: "Goose bump inducing maps as extreme cold warnings are in place for southern Ontario. Also, the city of Toronto has issued an extreme cold weather alert, which helps open warming centres. #staywarm #toronto @weathernetwork pic.twitter.com/Yl2A7fk953 / Twitter" Nicole Karkic on Twitter: "Goose bump inducing maps as extreme cold warnings are in place for southern Ontario. Also, the city of Toronto has issued an extreme cold weather alert, which helps open warming centres. #staywarm #toronto @weathernetwork pic.twitter.com/Yl2A7fk953 / Twitter" Nicole Karkic on Twitter: "Goose bump inducing maps as extreme cold warnings are in place for southern Ontario. Also, the city of Toronto has issued an extreme cold weather alert, which helps open warming centres. #staywarm #toronto @weathernetwork pic.twitter.com/Yl2A7fk953 / Twitter" Nicole Karkic on Twitter: "Goose bump inducing maps as extreme cold warnings are in place for southern Ontario. Also, the city of Toronto has issued an extreme cold weather alert, which helps open warming centres. #staywarm #toronto @weathernetwork pic.twitter.com/Yl2A7fk953 / Twitter"

— Nicole Karkic (@NicoleKarkic) Nicole Karkic on Twitter: "Goose bump inducing maps as extreme cold warnings are in place for southern Ontario. Also, the city of Toronto has issued an extreme cold weather alert, which helps open warming centres. #staywarm #toronto @weathernetwork pic.twitter.com/Yl2A7fk953 / Twitter"

High temperatures on both Friday and Saturday will come in colder than the seasonal low for the date, with Toronto’s high struggling to climb out of the negative teens both days. Blustery winds will make feels-like values much colder.

Sunny & frigid today but more clouds & flurries along the south shore of Lake Ontario (Niagara); Sunny & frigid Saturday (flurries Niagara); Cloudy, peeks of sun & flurries Sunday; Brief warm-up early next week; Potential for messy & high impact systems mid & late next week #onwx pic.twitter.com/iVUehUq1Z4

Sunny & frigid today but more clouds & flurries along the south shore of Lake Ontario (Niagara); Sunny & frigid Saturday (flurries Niagara); Cloudy, peeks of sun & flurries Sunday; Brief warm-up early next week; Potential for messy & high impact systems mid & late next week Doug Gillham on Twitter: "Sunny & frigid today but more clouds & flurries along the south shore of Lake Ontario (Niagara); Sunny & frigid Saturday (flurries Niagara); Cloudy, peeks of sun & flurries Sunday; Brief warm-up early next week; Potential for messy & high impact systems mid & late next week #onwx pic.twitter.com/iVUehUq1Z4 / Twitter" Doug Gillham on Twitter: "Sunny & frigid today but more clouds & flurries along the south shore of Lake Ontario (Niagara); Sunny & frigid Saturday (flurries Niagara); Cloudy, peeks of sun & flurries Sunday; Brief warm-up early next week; Potential for messy & high impact systems mid & late next week #onwx pic.twitter.com/iVUehUq1Z4 / Twitter"

— Doug Gillham (@gtaweather1) Doug Gillham on Twitter: "Sunny & frigid today but more clouds & flurries along the south shore of Lake Ontario (Niagara); Sunny & frigid Saturday (flurries Niagara); Cloudy, peeks of sun & flurries Sunday; Brief warm-up early next week; Potential for messy & high impact systems mid & late next week #onwx pic.twitter.com/iVUehUq1Z4 / Twitter"

Low temperatures will dip into the -20s for many areas on Saturday morning. Remain mindful of the potential for frostbite and hypothermia, especially if you have to spend a significant amount of time outdoors.

Environment Canada issued an extreme cold warning Friday morning, warning of "wind chill values between minus 30 and minus 35" for parts of southern Ontario, including Toronto.

"Risks are greater for young children, older adults, people with chronic illnesses, people working or exercising outdoors, and those without proper shelter," cautioned the agency in the statement. "Watch for cold related symptoms: shortness of breath, chest pain, muscle pain and weakness, numbness and colour change in fingers and toes."

EYES ON A SYSTEM MID-TO-LATE NEXT WEEK

Forecasters are keeping a close watch on a potentially high impact and messy storm mid and late next week for the Great Lakes, southern and eastern Ontario, and southern Quebec.

While precipitation types and amounts are still being analyzed, the one thing that is certain is that this region will be the battleground between warm air attempting to surge north, while frigid Arctic air sinks south into the area.

"A couple of systems will track along the boundary, but the exact position of the boundary is still uncertain," says meteorologist Dr. Doug Gillham. "Areas south of the boundary will see very mild temperatures and heavy rain, while areas to the north of the boundary will see a couple rounds of heavy snow. In between, we will see a messy mix of rain, significant ice and snow."

Residents are advised to check back regularly as we fine-tune the details of next week's potential storm.

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