September Weather in Ballard, United States

Last updated: June 24, 2025

In September, the average temperature in Ballard, United States is a mild 20°C (67°F). However, be prepared for a range of temperatures, with a minimum of 1°C (34°F) and a maximum soaring to 37°C (99°F). Expect some light showers, with an average precipitation of 18 mm (0.7 in) spread over 3 days. The air will be relatively comfortable, with an average humidity of 46%.

September Temperature in Ballard

In September in Ballard, the average temperature is 20°C (67°F). Maximums can reach 37°C (99°F), and minimums can be as low as 1°C (34°F). Travelers should be prepared for a wide range of temperatures during their visit.

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

The chart illustrates September temperature patterns in Ballard, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Ballard, September typically has an average temperature of 20°C (67°F), with highs reaching up to 37°C (99°F) and lows dropping to around 1°C (34°F).

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

September Precipitation in Ballard

In Ballard in September, the precipitation amount is 18 mm (0.7 in) over a span of 3 days.

September Precipitation Trends in Ballard

The chart displays monthly precipitation patterns in Ballard, 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 Ballard, September typically receives around 18 mm (0.7 inches) of precipitation spread over approximately 3 days.

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

Choose your preferred precipitation unit

Millimeters (mm) Inches (in)

September Humidity in Ballard

In Ballard in September, humidity is 46%. With an average temperature of 20°C (67°F), this humidity feels like a refreshing embrace, perfect for leisurely strolls and outdoor explorations.

September Average Humidity in Ballard

This chart illustrates the average monthly humidity levels in Ballard, 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 Ballard is approximately 46%, 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 Ballard

In Ballard in September, the maximum UV index reaches 10, which corresponds to a very high Exposure Category. With a time to burn of just 15 minutes, it's crucial to take precautions. For more detailed information, you can check the Hourly UV Index in Ballard.

Maximum UV Index Levels in Ballard for September

The chart shows the monthly maximum UV Index (UVI) for Ballard 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 Ballard typically reaches 10, which falls under the very high exposure category.

Data source: Ballard 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 Ballard Compares to Other Months

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

This table compares monthly weather conditions in Ballard, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	-4°C (25°F)	25 mm (1.0 inches)	91%	moderate
February Weather	-1°C (30°F)	29 mm (1.1 inches)	92%	high
March Weather	5°C (42°F)	36 mm (1.4 inches)	84%	very high
April Weather	10°C (51°F)	20 mm (0.8 inches)	74%	very high
May Weather	16°C (61°F)	25 mm (1.0 inches)	62%	extreme
June Weather	23°C (73°F)	12 mm (0.5 inches)	56%	extreme
July Weather	27°C (80°F)	11 mm (0.4 inches)	44%	extreme
August Weather	25°C (77°F)	14 mm (0.6 inches)	37%	extreme
September Weather	20°C (67°F)	18 mm (0.7 inches)	46%	very high
October Weather	9°C (49°F)	31 mm (1.2 inches)	67%	high
November Weather	4°C (39°F)	18 mm (0.7 inches)	84%	moderate
December Weather	-2°C (29°F)	23 mm (0.9 inches)	88%	moderate