The unique man-made climate
of New York City
Köppen Climate Classification in New York City
New York City has a Cfa humid subtropical climate, according to the Köppen climate classification. Without the city’s infrastructure, the region might fall into the Dfa humid continental zone. The urban heat island effect raises temperatures, especially during nights and winter. This man-made heat keeps the city warmer than the surrounding rural areas.
During winter, cold winds from Canada lower the temperature, but NYC remains about 2 to 3°C (5°F) warmer on average. Buildings, pavement, and human activity trap heat, pushing it out of the Dfa zone.
Cfa and Dfa Climate Zones Around New York
Just north of the city, the Dfa climate zone begins, with cooler conditions and less population. However, Long Island and the Hudson River Valley also fall under the Cfa climate due to their coastal location. The urban influence clearly plays a role, but natural factors also contribute to this climate classification.

Köppen climate classification
Rainfall and Precipitation Patterns in NYC
New York City experiences frequent and heavy rainfall. Annual precipitation reaches about 1,250 millimeters (50 inches). Spring is typically the wettest season, and February is the driest month. Every month in recorded history has had some rainfall, showing how variable the weather can be.
Summer Weather in New York City
Summers are warm to hot, often exceeding 30°C (86°F). High humidity levels make the air feel muggy. While cooling ocean breezes can help, heat waves are also common.
Summer winds mainly come from the warm southwest, bringing additional heat into the city.
Winter Climate and Snowfall in NYC
Winters are cold and windy, with northwest winds from Canada. Temperatures often fall below freezing, especially in January and February.
Despite the cold winds, the urban setting and ocean influence keep the city warmer than areas farther inland. Blizzards are common, especially when Atlantic moisture meets cold air from the continent.
Spring and Fall in NYC: What to Expect
Spring starts out cool but warms up quickly. Fall usually begins warm and cools down toward December. These seasons are generally mild, but tropical storms can occur in autumn.
One of the most damaging events was Hurricane Sandy, which hit the city on October 29, 2012. It caused severe flooding, power outages, and displaced thousands of residents.
Why NYC Subway Gets So Hot in Summer
The urban heat island effect is very noticeable in the New York City subway system. Temperatures in the tunnels often reach 40°C (104°F) during summer.
Air conditioners from subway trains, combined with poor ventilation, trap heat underground. This makes waiting on platforms extremely uncomfortable and impacts quality of life in the city.

The New York City Subway
Extreme Temperatures in New York City
The highest temperature ever recorded in NYC was 41°C (106°F) in 1936. The lowest temperature was -26°C (-15°F) in 1934.
Climate Change Impact on New York City
In 2019, NYC officially declared a climate emergency. The city faces serious climate risks, including:
-
More frequent heat waves (from 2 to 6 per year)
-
Hot days above 32°C (90°F) increasing from 18 to 57 per year
-
13% more annual precipitation
-
Rising sea levels, with an average increase of 3 cm (1.2 inches) per decade
Flooding, extreme heat, and heavier storms will continue to challenge the city in the future.
Final Thoughts: A Man-Made Climate in a Unique Location
New York City sits between a warm ocean current to the east and a cold continent to the west. This mix of natural and human-made factors gives the city a unique climate profile. From heat waves to snowstorms, NYC experiences it all — and urban life intensifies every weather condition.