May Weather in Eureka, United States

Last updated: June 24, 2025

In May, the average temperature in Eureka, United States hovers around 12°C (55°F). Temperatures can range from a chilly -5°C (23°F) to a warm 32°C (91°F). Expect about 39 mm (1.5 in) of precipitation over 9 days, contributing to an average humidity of 55%.

May Temperature in Eureka

In May in Eureka, the average temperature is 12°C (55°F). Maximum temperatures can reach 32°C (91°F), while minimums can dip as low as -5°C (23°F). Be prepared for a wide range of temperatures when visiting Eureka during this month!

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

The chart illustrates May 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, May typically has an average temperature of 12°C (55°F), with highs reaching up to 32°C (91°F) and lows dropping to around -5°C (23°F).

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

May Precipitation in Eureka

In Eureka in May, the precipitation amount is 39 mm (1.5 in) spread over 9 days.

May Precipitation Trends in Eureka

The chart displays monthly precipitation patterns in Eureka, with values for each month alongside May’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how May’s conditions compare to those of other months. In Eureka, May typically receives around 39 mm (1.5 inches) of precipitation spread over approximately 9 days.

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

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Millimeters (mm) Inches (in)

May Humidity in Eureka

In Eureka in May humidity is 55%. With an average temperature of 12°C (55°F), this humidity feels like a mild chill in the air, perfect for exploring the surroundings while still needing a light jacket for comfort.

May Average Humidity in Eureka

This chart illustrates the average monthly humidity levels in Eureka, with May’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In May, average humidity in Eureka is approximately 55%, offering insight into how humid the weather typically is during this month.

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

May UV Index in Eureka

In Eureka in May, the maximum UV index reaches 11, which corresponds to an extreme Exposure Category. With a time to burn of just 10 minutes, it's essential to take precautions. For more details, you can check the Hourly UV Index in Eureka.

Maximum UV Index Levels in Eureka for May

The chart shows the monthly maximum UV Index (UVI) for Eureka in May, 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 May, the maximum UV index in Eureka typically reaches 11, which falls under the extreme exposure category.

Data source: Eureka May 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 May 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 May’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 May’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	-4°C (25°F)	29 mm (1.1 inches)	84%	moderate
February Weather	-3°C (27°F)	29 mm (1.1 inches)	87%	high
March Weather	1°C (35°F)	57 mm (2.3 inches)	80%	very high
April Weather	8°C (46°F)	39 mm (1.5 inches)	71%	very high
May Weather	12°C (55°F)	39 mm (1.5 inches)	55%	extreme
June Weather	20°C (68°F)	10 mm (0.4 inches)	51%	extreme
July Weather	25°C (77°F)	16 mm (0.6 inches)	41%	extreme
August Weather	24°C (75°F)	9 mm (0.3 inches)	32%	extreme
September Weather	18°C (65°F)	12 mm (0.5 inches)	41%	very high
October Weather	9°C (48°F)	22 mm (0.9 inches)	61%	high
November Weather	4°C (39°F)	22 mm (0.8 inches)	79%	moderate
December Weather	-3°C (26°F)	29 mm (1.1 inches)	83%	moderate