August Weather in Hermiston, United States

Last updated: June 24, 2025

In August, the average temperature in Hermiston, United States hovers around 26°C (79°F), making it a pleasant time to visit. However, temperatures can swing dramatically, with a minimum of 9°C (49°F) and soaring up to 42°C (108°F). Expect the humidity to be around 60%, adding a bit of warmth to those sunny days. Precipitation is minimal, averaging only 5 mm (0.2 in) over 1 day, so you can likely enjoy clear skies during your stay!

August Temperature in Hermiston

In August in Hermiston, the average temperature is 26°C (79°F), with maximums reaching up to 42°C (108°F) and minimums dipping as low as 9°C (49°F). Be sure to pack accordingly, as you can experience both hot days and cooler nights during your travels.

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

The chart illustrates August temperature patterns in Hermiston, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Hermiston, August typically has an average temperature of 26°C (79°F), with highs reaching up to 42°C (108°F) and lows dropping to around 9°C (49°F).

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

August Precipitation in Hermiston

In Hermiston in August, the precipitation amount is 5 mm (0.2 in) over a duration of 1 day.

August Precipitation Trends in Hermiston

The chart displays monthly precipitation patterns in Hermiston, 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 Hermiston, August typically receives around 5 mm (0.2 inches) of precipitation spread over approximately 1 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 Hermiston

In Hermiston in August humidity is 60%. With an average temperature of 26°C (79°F), this humidity feels like walking through a warm, damp blanket, making any outdoor activities a bit more exhausting but still enjoyable as you soak in the vibrant atmosphere.

August Average Humidity in Hermiston

This chart illustrates the average monthly humidity levels in Hermiston, 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 Hermiston is approximately 60%, 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 Hermiston

In Hermiston in August, the maximum UV index is 9, which corresponds to a very high Exposure Category. The time to burn is just 15 minutes, so it's essential to take precautions. For detailed information, you can check the Hourly UV Index in Hermiston.

Maximum UV Index Levels in Hermiston for August

The chart shows the monthly maximum UV Index (UVI) for Hermiston 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 Hermiston typically reaches 9, which falls under the very high exposure category.

Data source: Hermiston 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 Hermiston Compares to Other Months

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

This table compares monthly weather conditions in Hermiston, showing how August’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	2°C (37°F)	40 mm (1.6 inches)	86%	low
February Weather	3°C (38°F)	54 mm (2.1 inches)	86%	moderate
March Weather	8°C (46°F)	40 mm (1.6 inches)	85%	high
April Weather	12°C (54°F)	31 mm (1.2 inches)	83%	high
May Weather	18°C (64°F)	17 mm (0.7 inches)	77%	very high
June Weather	22°C (72°F)	10 mm (0.4 inches)	81%	very high
July Weather	27°C (80°F)	0 mm (0.0 inches)	76%	very high
August Weather	26°C (79°F)	5 mm (0.2 inches)	60%	very high
September Weather	20°C (68°F)	12 mm (0.5 inches)	58%	high
October Weather	12°C (54°F)	29 mm (1.1 inches)	75%	moderate
November Weather	6°C (44°F)	39 mm (1.6 inches)	85%	moderate
December Weather	3°C (37°F)	40 mm (1.6 inches)	87%	low