Commuters dealt with bitter cold temperatures Friday ahead of possible record lows this weekend.
At the No. 6 train station in Hunts Point, straphangers wore layers and hurried indoors to avoid the cold. Some residents said that they weren't prepared for such brutal cold after the relatively mild winter so far.
Mayor Bill de Blasio issued a code blue warning urging New Yorkers to help take the homeless off the streets and bring them inside by calling 311. If residents see a homeless person who appears to be suffering from a medical emergency, the mayor urged them to call 911 instead.
The city is also under a wind chill advisory with temperatures expected to dip down into the single digits on Saturday and Sunday.
Wind gusts of up to 45 mph are expected, which results in a subzero wind chill factor.
Health officials say the bitter cold can cause health issues for people who spend too much time outside. They say people should cover their fingers, ears and noses and wear warm hats. They also recommend changing out of wet clothing quickly and avoiding alcohol.
Officials say symptoms of hypothermia, which can be life-threatening, include slurred speech, confusion and shallow breathing. Infants, seniors and people with general health issues are at higher risk for frostbite.
The freezing temperatures can also cause car trouble, according to experts. It can kill batteries and thicken motor oil.