I've corrected the climate records for the chart.  The source led to Dell Regional High School in New Jersey, not anywhere in New York City.  This was probably done so that the introduction of NYC's climate could say it lies entirely in the humid subtropical zone, with the coldest month averaging 0° C.  But the weather.com record for New York City shows the coldest month with an average high of 36 and a low of 23, averaging out to -1.3° C, placing it in the transition zone between humid subtropical and humid continental.  I will make that change as well.