August Weather in Eureka, United States

Last updated: June 24, 2025

In August, the average temperature in Eureka, United States hovers around 21°C (70°F). However, you can expect temperatures to vary dramatically, with a minimum of 8°C (46°F) and a scorching maximum of 36°C (97°F). This month also brings 102 mm (4.0 in) of precipitation spread over about 9 days, contributing to an average humidity of 82%. Prepare for a mix of warm days and refreshing showers!

August Temperature in Eureka

In August, in Eureka, the average temperature is 21°C (70°F). Maximum temperatures can reach 36°C (97°F), while minimums can drop as low as 8°C (46°F). Be sure to pack both lightweight clothing for the heat and layers for the cooler evenings during your travels.

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

The chart illustrates August temperature patterns in Eureka, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Eureka, August typically has an average temperature of 21°C (70°F), with highs reaching up to 36°C (97°F) and lows dropping to around 8°C (46°F).

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

August Precipitation in Eureka

In Eureka in August, the total precipitation amount is 102 mm (4.0 in) over a span of 9 days.

August Precipitation Trends in Eureka

The chart displays monthly precipitation patterns in Eureka, 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 Eureka, August typically receives around 102 mm (4.0 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 Eureka

In Eureka in August, humidity is 82%. With an average temperature of 21°C (70°F), this humidity feels like a warm, sticky embrace that can quickly lead to discomfort for travelers, making outdoor activities less enjoyable and requiring frequent breaks for hydration.

August Average Humidity in Eureka

This chart illustrates the average monthly humidity levels in Eureka, 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 Eureka is approximately 82%, 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 Eureka

In Eureka 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 Eureka.

Maximum UV Index Levels in Eureka for August

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

Data source: Eureka 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 Eureka Compares to Other Months

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

This table compares monthly weather conditions in Eureka, showing how August’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	-10°C (15°F)	14 mm (0.6 inches)	81%	low
February Weather	-11°C (13°F)	17 mm (0.7 inches)	85%	moderate
March Weather	-1°C (30°F)	29 mm (1.1 inches)	76%	moderate
April Weather	4°C (40°F)	43 mm (1.7 inches)	79%	high
May Weather	13°C (56°F)	57 mm (2.2 inches)	76%	very high
June Weather	21°C (70°F)	59 mm (2.3 inches)	81%	very high
July Weather	23°C (74°F)	63 mm (2.5 inches)	82%	very high
August Weather	21°C (70°F)	102 mm (4.0 inches)	82%	very high
September Weather	16°C (62°F)	69 mm (2.7 inches)	77%	very high
October Weather	7°C (44°F)	63 mm (2.5 inches)	76%	moderate
November Weather	0°C (32°F)	14 mm (0.5 inches)	84%	moderate
December Weather	-6°C (22°F)	27 mm (1.1 inches)	81%	low