nomadseason

September Weather in Allendale, United States

Last updated: June 24, 2025

In September, the average temperature in Allendale, United States hovers around 19°C (66°F), with a minimum dipping to 5°C (41°F) and a maximum reaching 31°C (88°F). Expect 109 mm (4.3 in) of precipitation over approximately 10 days, accompanied by an average humidity level of 79%. Prepare for a mix of mild warmth and occasional showers during your visit!

September Temperature in Allendale

In September in Allendale, the average temperature is 19°C (66°F). Maximums can reach 31°C (88°F), while minimums can drop to as low as 5°C (41°F). Pack versatile clothing to enjoy the varying temperatures while exploring this destination.

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 19°C (66°F), with highs reaching up to 31°C (88°F) and lows dropping to around 5°C (41°F).
JanFebMarAprMayJunJulAugSepOctNovDec272836445667737266544033
Data source: Temperature data for Allendale generated using information from the Copernicus Climate Change Service.
Choose your preferred temperature unit
The average of daily temperatures (24 hours) calculated across all days in the month.

September Precipitation in Allendale

In Allendale in September, the precipitation amount is 109 mm (4.3 in) spread over 10 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 109 mm (4.3 inches) of precipitation spread over approximately 10 days.
JanFebMarAprMayJunJulAugSepOctNovDec7074709813412062691091407574
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
Choose your preferred precipitation unit

September Humidity in Allendale

In Allendale in September humidity is 79%. With an average temperature of 19°C (66°F), this humidity feels like a warm embrace, making it feel much warmer than the actual temperature and creating a heavy, sticky atmosphere that can be a bit uncomfortable for traveling.

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 79%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec87%87%86%87%82%81%78%79%80%82%87%86%
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 7, which corresponds to the high Exposure Category. This means that the time to burn is approximately 25 minutes. For more 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 7, which falls under the high exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec24589101097532
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.
 TemperaturePrecipitationHumidityUV
January Weather-3°C (28°F)69 mm (2.7 inches)87%low
February Weather-2°C (28°F)74 mm (2.9 inches)87%moderate
March Weather2°C (36°F)70 mm (2.8 inches)86%moderate
April Weather7°C (44°F)98 mm (3.8 inches)87%very high
May Weather13°C (56°F)134 mm (5.3 inches)82%very high
June Weather19°C (67°F)120 mm (4.7 inches)81%very high
July Weather23°C (73°F)62 mm (2.4 inches)78%very high
August Weather22°C (72°F)69 mm (2.7 inches)79%very high
September Weather19°C (66°F)109 mm (4.3 inches)79%high
October Weather12°C (54°F)140 mm (5.5 inches)82%moderate
November Weather4°C (40°F)75 mm (3.0 inches)87%moderate
December Weather1°C (34°F)74 mm (2.9 inches)86%low

Compare Allendale's Climate with Cities Worldwide