September Weather in Onset, United States

Last updated: June 24, 2025

In Onset, United States, the average temperature for September hovers around 19°C (67°F), with a comfortable range from a minimum of 9°C (48°F) to a maximum of 30°C (87°F). You can expect about 102 mm (4.0 in) of precipitation spread over 10 days, complemented by an average humidity level of 75%.

September Temperature in Onset

In September in Onset, the average temperature is 19°C (67°F). Maximum temperatures can reach 30°C (87°F) while the minimum can drop as low as 9°C (48°F). This pleasant climate makes Onset an ideal destination for travelers seeking a comfortable and enjoyable experience.

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

The chart illustrates September temperature patterns in Onset, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Onset, September typically has an average temperature of 19°C (67°F), with highs reaching up to 30°C (87°F) and lows dropping to around 9°C (48°F).

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

September Precipitation in Onset

In Onset in September, the total precipitation amount is 102 mm (4.0 in) falling over the course of 10 days.

September Precipitation Trends in Onset

The chart displays monthly precipitation patterns in Onset, 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 Onset, September typically receives around 102 mm (4.0 inches) of precipitation spread over approximately 10 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 Onset

In Onset in September humidity is 75%. With an average temperature of 19°C (67°F), this humidity feels like a warm embrace, making travel invigorating yet slightly sticky, as you navigate through the vibrant streets or scenic landscapes.

September Average Humidity in Onset

This chart illustrates the average monthly humidity levels in Onset, 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 Onset is approximately 75%, 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 Onset

In Onset 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 Onset.

Maximum UV Index Levels in Onset for September

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

Data source: Onset 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 Onset Compares to Other Months

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

This table compares monthly weather conditions in Onset, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	1°C (34°F)	82 mm (3.2 inches)	84%	moderate
February Weather	2°C (36°F)	97 mm (3.8 inches)	84%	moderate
March Weather	4°C (39°F)	107 mm (4.2 inches)	82%	high
April Weather	9°C (48°F)	122 mm (4.8 inches)	79%	very high
May Weather	14°C (57°F)	98 mm (3.9 inches)	75%	very high
June Weather	19°C (67°F)	90 mm (3.5 inches)	78%	very high
July Weather	23°C (74°F)	102 mm (4.0 inches)	76%	very high
August Weather	23°C (74°F)	81 mm (3.2 inches)	76%	very high
September Weather	19°C (67°F)	102 mm (4.0 inches)	75%	very high
October Weather	14°C (58°F)	143 mm (5.6 inches)	75%	high
November Weather	8°C (46°F)	93 mm (3.7 inches)	80%	moderate
December Weather	3°C (38°F)	116 mm (4.6 inches)	80%	low