Hamiltonians woke up to the coldest Jan. 7 in recorded history on Tuesday, as the temperature dove to -24 C.

For people scurrying to work across frozen downtown sidewalks, that temperature felt even colder as frigid winds gusting up to 60 km/h made it feel as cold as -41 C (the all-time wind chill record is -43 C, set on Jan. 19, 1994).

It's not expected to warm up much. Tuesday's high is forecast to be -19 C, before dropping again. If Wednesday reaches its forecast low, -23 C  is also set to break the daily cold record, according to Environment Canada records.

Hamilton may get back to normal winter temperatures with average highs around -2 C and lows around -10 C by the weekend.

Environment Canada warning preparedness meteorologist Geoff Coulson said the cold temperatures are due to "a pipeline" of air rushing down from the north and cutting across a huge swath of North America. 

Cold air graphic

A graphic provided by area weather watcher Cory Elder on Monday shows the cold air, in green, surrounding Hamilton. The temperatures here are in Fahrenheit. ((Submitted))

What's saving Hamilton from the full force of the cold? Lake Ontario.

"It's helping moderate the temperature, to a degree" Coulson said, adding the prairies and northern Ontario cities are facing far colder temperatures.

Many have blamed the extreme cold across Canada and the U.S. Midwest on a "polar vortex." But Grimbsy-based weather watcher Corey Elder said the polar vortex is nothing new in Hamilton, and that it sits too high up in the atmosphere to affect the air you feel at street level.

Instead, Elder said, you can blame the Arctic air mass that's been dragged down over the prairies and across the U.S. Midwest, which is now blowing over Hamilton in the form of a bitingly cold southwest wind. 

Hamilton coping with conditions

Hamilton's medical officer of health extended a cold weather alert on Tuesday to extend the city's shelter operations. 

Elsewhere In the city, Hamilton paramedics said they're dealing with more slip-and-fall calls than normal amid the icy conditions. Cmdr. Ian Wright said most of the injuries have been minor, but he said there have been some hip injuries. 

Wright also warned Hamilton residents not to underestimate the cold in the coming days. 

"Try and prepare yourself well," Wright said.

"Keep your skin covered up … plan your day so you don't have to be outside too long."

Paramedics are also on high alert for exposure injuries like frostbite and hypothermia, as well as injuries relating to vehicle collisions.

Environment Canada wind chill chart

Environment Canada wind chill chart (Environment Canada)