While it is very cold, Action News found plenty of people braving the frigid weather.
Jonathon Hernandez and his crew of three installed 9,000 Christmas lights on trees in front of the Federal Building in Old City on Sunday afternoon.
"It does matter to me. I'm used to working out in the cold. It would have been nice if the sun was out but it is what it is," said Hernandez.
Christine Famiglietti was also forced into the cold today because of her job.
"No matter what I have to come out because I'm a dog walker," said Famiglietti.
She made sure to layer up and so did many pets in Rittenhouse Square earlier this morning.
Some Temple University students cut their afternoon into Center City short because of low temperatures.
"I'm freezing right now. I'm the coldest girl in Philadelphia," said Mallory Stone.
"Freezing, I need a hat and a scarf asap," said Alison Reilly.
Along with the first big cold of the season came warnings from the city.
The City of Philadelphia issued a "code blue" alert Saturday at 6:00 p.m. The alert was expected to end at noon Monday unless conditions stay the same or worsen. The alert means warns homeless people not to stay outside and means they cannot be turned away from shelters.
We've known for days this cold front would come but some, like a group of au pairs visiting the East Coast, weren't quite ready - even the ones from Austria and Germany, where cold weather is a way of life.
"It's really windy and in Austria we don't have wind like that because of the mountains," said Hanna Loretz.