September Weather in Belmont, United States

Last updated: June 24, 2025

In September, the average temperature in Belmont, United States hovers around 18°C (66°F). However, be prepared for a minimum dip to 2°C (37°F) and a possible high of 33°C (91°F). With 113 mm (4.4 in) of precipitation over about 10 days, the average humidity is a notable 74%, creating a lush and vibrant atmosphere.

September Temperature in Belmont

In September in Belmont, the average temperature is 18°C (66°F). The maximum can reach 33°C (91°F), while the minimum can drop as low as 2°C (37°F). Pack accordingly to experience a range of weather conditions during your travels!

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

The chart illustrates September temperature patterns in Belmont, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Belmont, September typically has an average temperature of 18°C (66°F), with highs reaching up to 33°C (91°F) and lows dropping to around 2°C (37°F).

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

September Precipitation in Belmont

In Belmont in September, the total precipitation amount is 113 mm (4.4 in) over a span of 10 days.

September Precipitation Trends in Belmont

The chart displays monthly precipitation patterns in Belmont, 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 Belmont, September typically receives around 113 mm (4.4 inches) of precipitation spread over approximately 10 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 Belmont

In Belmont in September humidity is 74%. With an average temperature of 18°C (66°F), this humidity feels like a warm, enveloping blanket, making travel slightly uncomfortable as you navigate through the muggy air, often leaving you yearning for a refreshing breeze.

September Average Humidity in Belmont

This chart illustrates the average monthly humidity levels in Belmont, 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 Belmont is approximately 74%, 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 Belmont

In Belmont in September, the maximum UV index is 8, which corresponds to a very high Exposure Category. This means that the time to burn is only 15 minutes. For more detailed information, you can refer to the Hourly UV Index in Belmont.

Maximum UV Index Levels in Belmont for September

The chart shows the monthly maximum UV Index (UVI) for Belmont 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 Belmont typically reaches 8, which falls under the very high exposure category.

Data source: Belmont 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 Belmont Compares to Other Months

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

This table compares monthly weather conditions in Belmont, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	-6°C (21°F)	50 mm (2.0 inches)	84%	moderate
February Weather	-5°C (23°F)	59 mm (2.3 inches)	85%	moderate
March Weather	3°C (37°F)	61 mm (2.4 inches)	84%	high
April Weather	8°C (47°F)	91 mm (3.6 inches)	83%	very high
May Weather	16°C (60°F)	141 mm (5.6 inches)	75%	very high
June Weather	22°C (71°F)	131 mm (5.2 inches)	79%	very high
July Weather	24°C (75°F)	93 mm (3.7 inches)	75%	very high
August Weather	22°C (71°F)	103 mm (4.1 inches)	69%	very high
September Weather	18°C (66°F)	113 mm (4.4 inches)	74%	very high
October Weather	11°C (51°F)	120 mm (4.7 inches)	79%	moderate
November Weather	2°C (37°F)	45 mm (1.8 inches)	88%	moderate
December Weather	-1°C (30°F)	43 mm (1.7 inches)	82%	low