September is one of the most pleasant times of year to travel to New York weather-wise. The average high temperature is 75F (24C) and the average low is 61F (16C). While the beginning of the month, is summer-like, the temperature rarely rises above 90F (32C).
The month of September in New York City experiences essentially constant cloud cover, with the percentage of time that the sky is overcast or mostly cloudy remaining about 37% throughout the month. The clearest day of the month is September 23, with clear, mostly clear, or partly cloudy conditions 64% of the time.