September Weather in Oakland, United States

Last updated: June 24, 2025

In September, the average temperature in Oakland, United States hovers around 18°C (65°F), creating a pleasant climate for various activities. Expect a minimum temperature of 2°C (35°F) and a maximum of 30°C (87°F), offering a wide range of weather experiences. With 126 mm (5.0 in) of precipitation spread over 11 days, it's wise to pack an umbrella. The average humidity stands at 67%, adding a touch of moisture to the air, perfect for enjoying the lush surroundings.

September Temperature in Oakland

In September in Oakland, the average temperature is 18°C (65°F). Maximum temperatures can reach 30°C (87°F), while minimums can drop as low as 2°C (35°F). Overall, it's a great time for travelers to enjoy a mix of warm and cool weather.

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

The chart illustrates September temperature patterns in Oakland, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Oakland, September typically has an average temperature of 18°C (65°F), with highs reaching up to 30°C (87°F) and lows dropping to around 2°C (35°F).

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

September Precipitation in Oakland

In Oakland in September, the total precipitation amount is 126 mm (5.0 in) spread over 11 days.

September Precipitation Trends in Oakland

The chart displays monthly precipitation patterns in Oakland, 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 Oakland, September typically receives around 126 mm (5.0 inches) of precipitation spread over approximately 11 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 Oakland

In Oakland in September humidity is 67%. With an average temperature of 18°C (65°F), this humidity feels like a mild blanket wrapping around you, making outdoor activities feel pleasantly refreshing, yet you may find yourself reaching for a drink more often to stay hydrated while exploring the sights.

September Average Humidity in Oakland

This chart illustrates the average monthly humidity levels in Oakland, 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 Oakland is approximately 67%, 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 Oakland

In Oakland 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 Oakland.

Maximum UV Index Levels in Oakland for September

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

Data source: Oakland 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 Oakland Compares to Other Months

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

This table compares monthly weather conditions in Oakland, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	-2°C (28°F)	91 mm (3.6 inches)	89%	moderate
February Weather	0°C (33°F)	131 mm (5.1 inches)	90%	moderate
March Weather	4°C (39°F)	114 mm (4.5 inches)	89%	high
April Weather	9°C (49°F)	133 mm (5.2 inches)	88%	very high
May Weather	15°C (60°F)	152 mm (6.0 inches)	80%	very high
June Weather	19°C (67°F)	145 mm (5.7 inches)	79%	very high
July Weather	22°C (72°F)	121 mm (4.8 inches)	74%	very high
August Weather	21°C (70°F)	98 mm (3.9 inches)	64%	very high
September Weather	18°C (65°F)	126 mm (5.0 inches)	67%	very high
October Weather	12°C (55°F)	115 mm (4.5 inches)	81%	high
November Weather	4°C (40°F)	91 mm (3.6 inches)	89%	moderate
December Weather	1°C (34°F)	115 mm (4.5 inches)	88%	low