September Weather in Harlem, United States

Last updated: June 24, 2025

In September, the average temperature in Harlem, United States is a pleasant 25°C (78°F). However, be prepared for fluctuations, as temperatures can dip to a cool 12°C (53°F) or soar to a sizzling 37°C (99°F). Expect about 81 mm (3.2 in) of precipitation spread over 8 days, with an average humidity level of 83%—perfect for those who enjoy a lush, tropical atmosphere!

September Temperature in Harlem

In September in Harlem, the average temperature is 25°C (78°F). Maximum temperatures can reach 37°C (99°F), while the minimum can drop as low as 12°C (53°F). It's a perfect time for travelers to enjoy warm days and cooler evenings, so be sure to pack accordingly!

September Weather in Harlem: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Harlem, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Harlem, September typically has an average temperature of 25°C (78°F), with highs reaching up to 37°C (99°F) and lows dropping to around 12°C (53°F).

Data source: Temperature data for Harlem generated using information from the Copernicus Climate Change Service.

September Precipitation in Harlem

In Harlem in September, the precipitation amount is 81 mm (3.2 in) over the course of 8 days.

September Precipitation Trends in Harlem

The chart displays monthly precipitation patterns in Harlem, with values for each month alongside September’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how September’s conditions compare to those of other months. In Harlem, September typically receives around 81 mm (3.2 inches) of precipitation spread over approximately 8 days.

Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.

Choose your preferred precipitation unit

Millimeters (mm) Inches (in)

September Humidity in Harlem

In Harlem in September, humidity is 83%. With an average temperature of 25°C (78°F), this humidity feels like stepping into a warm, damp embrace, making travel sticky and exhausting, as each movement can leave you drenched in sweat.

September Average Humidity in Harlem

This chart illustrates the average monthly humidity levels in Harlem, with September’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In September, average humidity in Harlem is approximately 83%, offering insight into how humid the weather typically is during this month.

Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Harlem

In Harlem in September, the maximum UV index is 9, which corresponds to a very high Exposure Category. The time to burn is just 15 minutes, so it's essential to take precautions. For detailed information, you can check the Hourly UV Index in Harlem.

Maximum UV Index Levels in Harlem for September

The chart shows the monthly maximum UV Index (UVI) for Harlem in September, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues. In September, the maximum UV index in Harlem typically reaches 9, which falls under the very high exposure category.

Data source: Harlem September UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

Extreme (11+): Avoid the sun, stay in shade.
Very High (8-10): Limit sun exposure.
High (6-7): Use SPF 30+ and protective clothing.
Moderate (3-5): Midday shade recommended.
Low (0-2): No protection needed.

How September Weather in Harlem Compares to Other Months

Weather in Harlem varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Harlem, focusing on differences in temperature, rainfall, humidity, and UV levels.

This table compares monthly weather conditions in Harlem, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	9°C (49°F)	87 mm (3.4 inches)	86%	moderate
February Weather	12°C (54°F)	118 mm (4.6 inches)	81%	high
March Weather	15°C (59°F)	82 mm (3.2 inches)	81%	very high
April Weather	19°C (66°F)	106 mm (4.2 inches)	79%	very high
May Weather	23°C (74°F)	106 mm (4.2 inches)	75%	extreme
June Weather	26°C (79°F)	109 mm (4.3 inches)	75%	extreme
July Weather	28°C (82°F)	113 mm (4.4 inches)	80%	extreme
August Weather	27°C (81°F)	125 mm (4.9 inches)	81%	very high
September Weather	25°C (78°F)	81 mm (3.2 inches)	83%	very high
October Weather	21°C (70°F)	91 mm (3.6 inches)	78%	very high
November Weather	13°C (56°F)	69 mm (2.7 inches)	85%	high
December Weather	11°C (51°F)	117 mm (4.6 inches)	87%	moderate