August Weather in Washington, United States

Last updated: June 24, 2025

In August, the average temperature in Washington, United States is a warm 27°C (81°F). Expect minimums around 17°C (63°F) and maximums peaking at 36°C (97°F). With 125 mm (4.9 in) of precipitation spread over 16 days, you'll want to be prepared for some rain. The average humidity sits at a steamy 81%, making for a tropical feel throughout the month.

August Temperature in Washington

In August in Washington, the average temperature is 27°C (81°F). Maximums can reach 36°C (97°F), while minimums can dip as low as 17°C (63°F). This makes it an ideal time for travelers seeking warm weather and pleasant conditions.

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 27°C (81°F), with highs reaching up to 36°C (97°F) and lows dropping to around 17°C (63°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 125 mm (4.9 in) spread over 16 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 125 mm (4.9 inches) of precipitation spread over approximately 16 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 81%. With an average temperature of 27°C (81°F), this humidity feels like a warm, heavy blanket enveloping you, making travel quite uncomfortable as it can quickly drain your energy and require frequent hydration breaks.

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 81%, 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 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 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 10, 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	9°C (48°F)	100 mm (3.9 inches)	86%	moderate
February Weather	12°C (53°F)	117 mm (4.6 inches)	84%	high
March Weather	14°C (58°F)	87 mm (3.4 inches)	83%	very high
April Weather	18°C (65°F)	107 mm (4.2 inches)	81%	very high
May Weather	23°C (73°F)	109 mm (4.3 inches)	81%	extreme
June Weather	26°C (79°F)	97 mm (3.8 inches)	81%	extreme
July Weather	27°C (82°F)	105 mm (4.1 inches)	83%	extreme
August Weather	27°C (81°F)	125 mm (4.9 inches)	81%	very high
September Weather	25°C (77°F)	98 mm (3.9 inches)	82%	very high
October Weather	20°C (68°F)	112 mm (4.4 inches)	78%	very high
November Weather	12°C (54°F)	82 mm (3.2 inches)	86%	high
December Weather	10°C (50°F)	117 mm (4.6 inches)	89%	moderate