September Weather in Allendale, United States

Last updated: June 24, 2025

In Allendale, United States, the average temperature in September hovers around 23°C (74°F), making for a pleasant climate. However, be prepared for a temperature range that can dip to 6°C (43°F) or spike up to a sizzling 45°C (113°F)! Fortunately, the area experiences minimal precipitation, with just 1 mm (0.0 in) over 0 days, and the average humidity remains comfortable at 44%.

September Temperature in Allendale

In September in Allendale, the average temperature is 23°C (74°F). Maximums can reach 45°C (113°F) and minimums can be as low as 6°C (43°F). Be prepared for a wide range of temperatures when traveling, so bring both light clothing for the heat and warmer layers for cooler evenings.

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

The chart illustrates September temperature patterns in Allendale, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Allendale, September typically has an average temperature of 23°C (74°F), with highs reaching up to 45°C (113°F) and lows dropping to around 6°C (43°F).

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

September Precipitation in Allendale

In Allendale in September, the precipitation amount is 1 mm (0.0 in) during a span of 0 days.

September Precipitation Trends in Allendale

The chart displays monthly precipitation patterns in Allendale, 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 Allendale, September typically receives around 1 mm (0.0 inches) of precipitation spread over approximately 0 days.

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

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Millimeters (mm) Inches (in)

September Humidity in Allendale

In Allendale in September humidity is 44%. With an average temperature of 23°C (74°F), this humidity feels like a comfortable embrace, making it pleasant for traveling and exploring the sights without feeling overly hot or sticky.

September Average Humidity in Allendale

This chart illustrates the average monthly humidity levels in Allendale, 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 Allendale is approximately 44%, 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 Allendale

In Allendale 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 Allendale.

Maximum UV Index Levels in Allendale for September

The chart shows the monthly maximum UV Index (UVI) for Allendale 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 Allendale typically reaches 9, which falls under the very high exposure category.

Data source: Allendale 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 Allendale Compares to Other Months

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

This table compares monthly weather conditions in Allendale, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	10°C (50°F)	124 mm (4.9 inches)	84%	moderate
February Weather	12°C (54°F)	106 mm (4.2 inches)	84%	moderate
March Weather	13°C (56°F)	79 mm (3.1 inches)	83%	high
April Weather	17°C (62°F)	30 mm (1.2 inches)	81%	very high
May Weather	20°C (68°F)	18 mm (0.7 inches)	74%	very high
June Weather	24°C (75°F)	2 mm (0.1 inches)	64%	extreme
July Weather	25°C (77°F)	0 mm (0.0 inches)	44%	extreme
August Weather	24°C (76°F)	0 mm (0.0 inches)	36%	very high
September Weather	23°C (74°F)	1 mm (0.0 inches)	44%	very high
October Weather	19°C (66°F)	27 mm (1.1 inches)	65%	high
November Weather	13°C (56°F)	38 mm (1.5 inches)	84%	moderate
December Weather	10°C (50°F)	85 mm (3.3 inches)	83%	moderate