The annual anticipation for the first snowfall in New York City marks the unofficial arrival of winter. Official records, including the average date and record extremes for snow, are maintained by the National Weather Service. All meteorological data is collected at the observation station located in Central Park. Analyzing this historical data provides a clear picture of when residents can typically expect the first snow.
How Official First Snow Is Defined
The official determination of the “first snow” date depends on the difference between trace amounts and measurable accumulation. Trace snow, symbolized by a capital “T” in weather logs, means snowflakes fell but were not enough to be registered by standard measuring equipment. This amount is too small to be quantified, though flakes may be visible on the ground or windshields.
For an event to qualify as the official “first measurable snowfall,” the accumulation must reach at least 0.1 inches (approximately 0.25 centimeters) in the official snow gauge. This threshold ensures consistency when calculating seasonal averages and setting historical records. The date recorded as the first snow is the first day of the season on which this 0.1-inch benchmark is met.
The Average Date for NYC’s First Snow
The current statistical average date for New York City’s first measurable snowfall falls on December 13. This date is derived from the most recent 30-year climate period (1991 through 2020). Calculating the average over three decades provides a stable measure that accounts for natural year-to-year variability.
While December 13 is the mean date, the typical range for the first measurable snow often begins in late November and extends through the end of December. The closer a date is to the middle of this range, the more aligned it is with climatological expectations for the region. A first measurable snowfall occurring outside of this four-to-five-week window is considered an outlier that deviates from the norm.
The city’s proximity to the Atlantic Ocean, which retains heat longer than land, contributes to the average date falling in mid-December. This maritime influence keeps temperatures warmer, often resulting in precipitation falling as rain during November and early December. A sustained cold air mass is typically required, often arriving after the Thanksgiving holiday, before conditions for measurable snow are consistently met.
Record-Breaking Extremes: Earliest and Latest
The historical record for the first measurable snowfall highlights the variability of the city’s winter weather. The latest date on record occurred on February 1, 2023, marking an unusually mild start to the season. Conversely, the earliest measurable snowfall occurred on October 29, 2011, when an unseasonal storm dropped 2.9 inches of snow. These two dates, October 29 and February 1, represent the widest possible seasonal span for the first measurable snow.