August Weather in Washington, United States

Last updated: June 24, 2025

In August, the average temperature in Washington, United States is a pleasant 20°C (68°F). Expect a minimum of 10°C (49°F) and a maximum reaching up to 31°C (88°F). During this time, precipitation amounts to 81 mm (3.2 in) over approximately 9 days, contributing to an average humidity of 74%.

August Temperature in Washington

In August in Washington, the average temperature is 20°C (68°F), with maximums reaching 31°C (88°F) and minimums dipping as low as 10°C (49°F). This pleasant climate makes it an ideal time for travelers to explore the area comfortably.

August Weather in Washington: Daily Temperature Highs, Lows, and Averages

The chart illustrates August temperature patterns in Washington, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Washington, August typically has an average temperature of 20°C (68°F), with highs reaching up to 31°C (88°F) and lows dropping to around 10°C (49°F).

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

August Precipitation in Washington

In Washington in August, the precipitation amount is 81 mm (3.2 in) spread over a duration of 9 days.

August Precipitation Trends in Washington

The chart displays monthly precipitation patterns in Washington, with values for each month alongside August’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how August’s conditions compare to those of other months. In Washington, August typically receives around 81 mm (3.2 inches) of precipitation spread over approximately 9 days.

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

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Millimeters (mm) Inches (in)

August Humidity in Washington

In Washington in August humidity is 74%. With an average temperature of 20°C (68°F), this humidity feels like a warm, sticky embrace that can make outdoor activities feel exhausting, prompting travelers to seek shade and hydration more often.

August Average Humidity in Washington

This chart illustrates the average monthly humidity levels in Washington, with August’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In August, average humidity in Washington is approximately 74%, offering insight into how humid the weather typically is during this month.

Data source: Humidity data for August generated using information from the Copernicus Climate Change Service.

August UV Index in Washington

In Washington in August, 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 Washington.

Maximum UV Index Levels in Washington for August

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

Data source: Washington August 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 August Weather in Washington Compares to Other Months

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

This table compares monthly weather conditions in Washington, showing how August’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	-3°C (26°F)	97 mm (3.8 inches)	88%	low
February Weather	-3°C (27°F)	95 mm (3.7 inches)	88%	moderate
March Weather	0°C (33°F)	78 mm (3.1 inches)	85%	moderate
April Weather	6°C (43°F)	141 mm (5.6 inches)	81%	high
May Weather	11°C (53°F)	92 mm (3.6 inches)	76%	very high
June Weather	17°C (62°F)	72 mm (2.8 inches)	74%	very high
July Weather	20°C (68°F)	102 mm (4.0 inches)	74%	very high
August Weather	20°C (68°F)	81 mm (3.2 inches)	74%	very high
September Weather	17°C (62°F)	83 mm (3.2 inches)	77%	high
October Weather	11°C (52°F)	143 mm (5.6 inches)	82%	moderate
November Weather	4°C (40°F)	121 mm (4.8 inches)	85%	moderate
December Weather	-1°C (30°F)	135 mm (5.3 inches)	84%	low