Under the Köppen climate classification, using the 0 °C . Annually, the city averages 234 days with at least some sunshine. The city lies in the USDA 7b plant hardiness zone.
Winters are chilly and damp, and prevailing wind patterns that blow sea breezes offshore temper the moderating effects of the Atlantic Ocean; yet the Atlantic and the partial shielding from colder air by the Appalachian Mountains keep the city warmer in the winter than inland North American cities at similar or lesser latitudes such as Pittsburgh, Cincinnati, and Indianapolis. The daily mean temperature in January, the area’s coldest month, is 33.7 °F (0.9 °C). Temperatures usually drop to 10 °F (−12 °C) several times per winter, yet can also reach 60 °F (16 °C) for several days even in the coldest winter month. Spring and autumn are unpredictable and can range from cool to warm, although they are usually mild with low humidity. Summers are typically hot and humid, with a daily mean temperature of 77.5 °F (25.3 °C) in July.
Nighttime temperatures are often enhanced due to the urban heat island effect. Daytime temperatures exceed 90 °F (32 °C) on average of 17 days each summer and in some years exceed 100 °F (38 °C), although this is a rare achievement, last occurring on July 18, 2012. Similarly, readings of 0 °F (−18 °C) are also extremely rare, last occurring on February 14, 2016. Extreme temperatures have ranged from −15 °F (−26 °C), recorded on February 9, 1934, up to 106 °F (41 °C) on July 9, 1936; the coldest recorded wind chill was −37 °F (−38 °C) on the same day as the all-time record low. The record cold daily maximum was 2 °F (−17 °C) on December 30, 1917, while, conversely, the record warm daily minimum was 87 °F (31 °C), on July 2, 1903. The average water temperature of the nearby Atlantic Ocean ranges from 39.7 °F (4.3 °C) in February to 74.1 °F (23.4 °C) in August.
The city receives 49.5 inches (1,260 mm) of precipitation annually, which is relatively evenly spread throughout the year. Average winter snowfall between 1981 and 2010 has been 29.8 inches (76 cm); this varies considerably between years. Hurricanes and tropical storms are rare in the New York area. Hurricane Sandy brought a destructive storm surge to New York City on the evening of October 29, 2012, flooding numerous streets, tunnels, and subway lines in Lower Manhattan and other areas of the city and cutting off electricity in many parts of the city and its suburbs. The storm and its profound impacts have prompted the discussion of constructing seawalls and other coastal barriers around the shorelines of the city and the metropolitan area to minimize the risk of destructive consequences from another such event in the future.
The coldest month on record is January 1857, with a mean temperature of 19.6 °F (−6.9 °C) whereas the warmest months on record are July 1825 and July 1999, both with a mean temperature of 81.4 °F (27.4 °C). The warmest years on record are 2012 and 2020, both with mean temperatures of 57.1 °F (13.9 °C). The coldest year is 1836, with a mean temperature of 47.3 °F (8.5 °C). The driest month on record is June 1949, with 0.02 inches (0.51 mm) of rainfall. The wettest month was August 2011, with 18.95 inches (481 mm) of rainfall. The driest year on record is 1965, with 26.09 inches (663 mm) of rainfall. The wettest year was 1983, with 80.56 inches (2,046 mm) of rainfall. The snowiest month on record is February 2010, with 36.9 inches (94 cm) of snowfall. The snowiest season (Jul–Jun) on record is 1995–1996, with 75.6 inches (192 cm) of snowfall. The least snowy season was 1972–1973, with 2.3 inches (5.8 cm) of snowfall. The earliest seasonal trace of snowfall occurred on October 10, in both 1979 and 1925. The latest seasonal trace of snowfall occurred on May 9, in both 2020 and 1977.