Extreme cold warning in effect for Windsor-Essex, Chatham-Kent, Sarnia

Much of southwestern Ontario is under an extreme cold warning for Monday night, including Windsor-Essex, Chatham-Kent and Sarnia.

Wind chill values will approach -30 C late Monday and early Tuesday, according to Environment and Climate Change Canada.

"We've got skies clearing under a very cold Arctic air mass, expecting temperatures to dip down to about -19," said Warning Preparedness Meteorologist Geoff Coulson.

"But when we factor in the wind chill, it's going to feel close to -30."

Wind chills in southwestern Ontario have already been hoving between -15 and -20 throughout Monday, Coulson said.

But they will continue to drop overnight.

People who don't need to be outside at night are better off staying indoors, Coulson said. 

And people who do should dress for the conditions because frostbite can develop within minutes on exposed skin.

The weather office is alerting people to the risks of extreme cold, urging them to watch for shortness of breath, chest pain, muscle pain and weakness, numbness and colour change in fingers and toes.

"Risks are greater for young children, older adults, people with chronic illnesses, people working or exercising outdoors, and those without proper shelter," it said in the weather warning.

If it's too cold for you to stay outside, it's too cold for your pet to stay outside, the warning said.

Temperatures will continue to be chilly throughout the rest of the week, Coulson said.

Overnight lows on Tuesday night are expected to hit -17 with a wind chill of -22, he said. 

They should warm up to seasonal norms on Friday.