Christmas eve of our coldest December in our lifetimes.
It looks like the climate there has warmed too, -20 and colder readings there were more common in the past and must be like 0 and below for NYC-- MPO's coldest temperature on record is -35 from back in 1912.
http://climate.met.psu.edu/data/city_information/lcds/mpo.php#:~:text=The lowest temperature ever recorded,in the form of snow.
The lowest temperature ever recorded at Mt. Pocono was -35 degrees on January 14, 1912.