nomadseason

September Weather in Hamilton, United States

Last updated: June 24, 2025

In September, the average temperature in Hamilton, United States hovers around 11°C (53°F). During this time, temperatures can dip as low as -8°C (18°F) or soar up to 31°C (89°F). Expect about 45 mm (1.8 in) of precipitation spread over 7 days, contributing to an overall average humidity of 67%.

September Temperature in Hamilton

In September in Hamilton, the average temperature is 11°C (53°F). The maximum can reach 31°C (89°F), while the minimum can be as low as -8°C (18°F). Pack versatile clothing to enjoy the wide range of temperatures during your travels.

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

The chart illustrates September temperature patterns in Hamilton, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Hamilton, September typically has an average temperature of 11°C (53°F), with highs reaching up to 31°C (89°F) and lows dropping to around -8°C (18°F).
JanFebMarAprMayJunJulAugSepOctNovDec212130344354646252362720
Data source: Temperature data for Hamilton 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 Hamilton

In Hamilton in September, the precipitation amount is 45 mm (1.8 in) spread over a duration of 7 days.

September Precipitation Trends in Hamilton

The chart displays monthly precipitation patterns in Hamilton, 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 Hamilton, September typically receives around 45 mm (1.8 inches) of precipitation spread over approximately 7 days.
JanFebMarAprMayJunJulAugSepOctNovDec6513882887694263245858188
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
Choose your preferred precipitation unit

September Humidity in Hamilton

In Hamilton in September humidity is 67%. With an average temperature of 11°C (53°F), this humidity feels like a damp chill that can make outdoor activities less enjoyable, often leading travelers to seek refuge indoors or dress in layers to stay comfortable.

September Average Humidity in Hamilton

This chart illustrates the average monthly humidity levels in Hamilton, 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 Hamilton is approximately 67%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec93%92%89%85%80%78%77%66%67%77%89%95%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Hamilton

In Hamilton 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 Hamilton.

Maximum UV Index Levels in Hamilton for September

The chart shows the monthly maximum UV Index (UVI) for Hamilton 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 Hamilton typically reaches 8, which falls under the very high exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec246810101098532
Data source: Hamilton 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 Hamilton Compares to Other Months

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

This table compares monthly weather conditions in Hamilton, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
 TemperaturePrecipitationHumidityUV
January Weather-6°C (22°F)65 mm (2.6 inches)93%low
February Weather-6°C (21°F)138 mm (5.4 inches)92%moderate
March Weather-1°C (30°F)82 mm (3.2 inches)89%high
April Weather1°C (34°F)88 mm (3.4 inches)85%very high
May Weather6°C (43°F)76 mm (3.0 inches)80%very high
June Weather12°C (54°F)94 mm (3.7 inches)78%very high
July Weather18°C (64°F)26 mm (1.0 inches)77%very high
August Weather17°C (62°F)32 mm (1.2 inches)66%very high
September Weather11°C (53°F)45 mm (1.8 inches)67%very high
October Weather2°C (37°F)85 mm (3.4 inches)77%moderate
November Weather-3°C (27°F)81 mm (3.2 inches)89%moderate
December Weather-7°C (20°F)88 mm (3.5 inches)95%low

Compare Hamilton's Climate with Cities Worldwide