In the Northeastern United States the average first frost date ranges from mid-September in higher altitudes to late-November in locations near the coast south of the New York City area.

Based on data from 1991 to 2020, the average first frost date for Central Park is November 20th, but with a wide range of experienced first frosts from October 15th to December 22nd. In Bridgeport CT the average first frost date is November 4th with a range of October 9th to November 26th. In Newark NJ the average first frost date is November 8th with a range of October 8th to December 2nd. At Kennedy Airport on Long Island the average first frost date is November 17th with a range of October 19th to December 17th.

NOAA has maps on its website that will help you anticipate the first freeze in your area of the United States. It indicates the historical average date for first freeze as well as a ten year range. Bear in mind that these dates are guidelines but can't perfectly predict the future and it is safer to err on the side of caution with plant care. The actual experienced first frost date can vary by several weeks in any given year. Always consult your local long-range weather forecast before making plant care decisions.

The National Weather Service has some useful resources that predict climate factors with an extended outlook. The forecasts are very general but can be useful in informing gardening decisions.

See also When is the Last Frost Date of spring in the New York City area?

Courtesy of NYBG Plant Information Service