If you are outside you can feel the bitter cold, but it's sometimes tough to see.
So we tried an experiment.
You take a wet t-shirt put it outdoors and in a matter of minutes it's frozen solid.
That's exactly how many people in Rochester felt today, frozen.
Whether you were on four legs like Gracie who bundled up in her finest coat for a walk.
"Today, around the block!" said Eamon Cregan, who walked his neighbor's dog.
Usually it's three miles.
"You want the breeze to your back, but once it is in your face, it is kind of rough I will tell you that," said Cregan.
Many schools and businesses shut down for the day.
Only those who had to trek out did.
"wouldn't be outside if I didn't have an appointment to go to. Me and cold does not work whatsoever" Tanisha Robinson, who waited for a bus in downtown Rochester.
"When we got down here it said four degrees - I am like ooh--- it went up one," said Tanyk'e Morgan, who waited for a bus.
The brave waited for a bus and took shelter under a few working heaters.
"Slightly under-prepared," said Benjamin Miles, who waited for bus without gloves.
The key was layers - lots of them.
“I wore my Buffalo Bills scarf, my ski jacket, and my hat, but I can't find my glove," said Charles Githler, who walked to lunch.
Tow truck drivers were busy.
With the cold came ice.
"everything has been auto all the overpasses are iced right over so it's just one accident right after the other you're cleaning one up and another is happening right behind you," said Bob Gropp, East Avenue Auto Manager
It's a day that left many feeling the chill of the 'Polar Vortex.'
"It's so cold even my Eskimo dog doesn't want to go out, not for long anyway," said Githler.
Children and the elderly feel the effects of the cold the most.
So don't let kids play outside too long. And if you can, check on neighbors and elderly relatives.