Last updated: June 24, 2025
In May, the average temperature in Eureka, United States hovers around 9°C (48°F), offering a cool yet pleasant climate. Be prepared for temperature fluctuations, with a minimum dipping to -5°C (23°F) and a comfortable maximum reaching 27°C (81°F). Expect about 64 mm (2.5 in) of precipitation spread over 12 days, coupled with an average humidity of 83%, creating a refreshing atmosphere perfect for outdoor adventures!
In May in Eureka, the average temperature is 9°C (48°F). The maximum can reach 27°C (81°F), and the minimum can be as low as -5°C (23°F). This range makes it an ideal time for travelers seeking a mix of mild weather and the chance to experience both warm days and cool nights.
In Eureka in May, the total precipitation amount is 64 mm (2.5 in) over the course of 12 days.
In Eureka in May humidity is 83%. With an average temperature of 9°C (48°F), this humidity feels like an enveloping blanket, making outdoor activities quite uncomfortable and encouraging travelers to seek shelter or shade frequently.
In Eureka in May, 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 Eureka.
UV Risk Categories
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.
| Temperature | Precipitation | Humidity | UV | |
|---|---|---|---|---|
| January Weather | -7°C (20°F) | 51 mm (2.0 inches) | 95% | low |
| February Weather | -9°C (16°F) | 70 mm (2.8 inches) | 93% | moderate |
| March Weather | -2°C (29°F) | 58 mm (2.3 inches) | 91% | moderate |
| April Weather | 3°C (37°F) | 66 mm (2.6 inches) | 88% | high |
| May Weather | 9°C (48°F) | 64 mm (2.5 inches) | 83% | very high |
| June Weather | 13°C (56°F) | 68 mm (2.7 inches) | 80% | very high |
| July Weather | 18°C (64°F) | 23 mm (0.9 inches) | 82% | very high |
| August Weather | 17°C (63°F) | 29 mm (1.2 inches) | 71% | very high |
| September Weather | 11°C (53°F) | 38 mm (1.5 inches) | 71% | high |
| October Weather | 3°C (38°F) | 70 mm (2.7 inches) | 85% | moderate |
| November Weather | -1°C (31°F) | 69 mm (2.7 inches) | 90% | low |
| December Weather | -5°C (24°F) | 76 mm (3.0 inches) | 96% | low |