The best times to visit Eureka for ideal weather are
June 18th to September 30th
based on average temperature and humidity from NOAA (the National Oceanic and Atmospheric Administration). Read below for more weather and travel details.
Eureka Travel Guide
Other Eureka Travel Info
Weather in Eureka
Average temperatures in Eureka vary little. Considering humidity, temperatures feel cold for most of the year with a fair chance of precipitation about half of the year. The area is less temperate than some — in the 28th percentile for pleasant weather — compared to tourist destinations worldwide. Weeks with ideal weather are listed above. If you’re looking for the very warmest time to visit Eureka, the hottest months are August, July, and then September. See average monthly temperatures below. The warmest time of year is generally late August to early September where highs are regularly around 67.3°F (19.6°C) with temperatures rarely dropping below 49.5°F (9.7°C) at night.
Eureka Temperatures (Fahrenheit)
Eureka Temperatures (Celsius)
The way we experience weather isn’t all about temperature. Higher temperatures affect us much more at higher humidity, and colder temperatures feel piercing with high winds. Our perceived temperatures factor in humidity and wind chill to better represent how hot or cold the day feels to a person.
Eureka Perceived Temperature (F)
Eureka Perceived Temperature (C)
Average Eureka Temperatures by Month
Daily highs (averaged for the month) usually give the best indication of the weather. A significantly lower mean and low generally just means it gets colder at night.
|Month||Avg. High (°F)||Avg. Mean (°F)||Avg. Low (°F)|
|Month||Avg. High (°C)||Avg. Mean (°C)||Avg. Low (°C)|
Precipitation (Rain or Snow)
If dry weather is what you’re after, the months with the lowest chance of significant precipitation in Eureka are August, July, and then September. Note that we define “significant precipitation” as .1 inches or more in this section. The lowest chance of rain or snow occurs around mid June. For example, on the week of June 18th there are no days of precipitation on average. By contrast, it’s most likely to rain or snow in mid December with an average of 4 days of significant precipitation the week of December 17th.
When can you find snow in Eureka? Weather stations report a bit of annual snow likely to be deepest around December, especially close to late November to early December. The best time to ski (if at all) in Eureka is often around around November 26th when fresh powder is deepest. Please note that a value of 0 for snow in the graph below may either mean there was no snow, or that snow is unreported.
Chance of Precipitation
The graph below shows the % chance of rainy and snowy days in Eureka.
Snow on the Ground
The graph below shows the average snow on the ground in Eureka (in).
Average Rain and Snow by Month
|Month||Daily Chance of Rain||Average Snow Depth (in)||Total Precipitation (in)|
|Month||Daily Chance of Rain||Average Snow Depth (cm)||Total Precipitation (cm)|
Humidity and Wind
Eureka has some extremely humid months, and high humidity throughout the year. The least humid month is February (75.4% relative humidity), and the most humid month is August (84.6%).
Wind in Eureka is usually calm. The windiest month is May, followed by April and March. May’s average wind speed of around 5.8 knots (6.6 MPH or 10.7 KPH) is considered “a light breeze.” Maximum sustained winds (the highest speed for the day lasting more than a few moments) are at their highest in early to mid June where average top sustained speeds reach 13 knots, which is considered a moderate breeze.
Relative Humidity (%)
The graph below shows the average % humidity by month in Eureka.
The graph below shows wind speed (max and average) in knots.
Average Wind Speeds
Show Wind Speeds
All wind speeds are in knots. 1 knot = 1.15 MPH or 1.85 KPH.
|Month||Avg. Wind||Avg. Wind Feel||Sustained High Wind||High Wind Feel|
|Jan||3.8||Barely noticeable||7.2||Gentle breeze|
|Feb||4.8||Light breeze||9.4||Gentle breeze|
|Mar||5.6||Light breeze||10.3||Gentle breeze|
|Apr||5.7||Light breeze||11||Significant breeze|
|May||5.8||Light breeze||11.2||Gentle breeze|
|Jun||5.5||Light breeze||11.1||Significant breeze|
|Jul||4.5||Light breeze||9||Gentle breeze|
|Aug||4.2||Light breeze||8.3||Gentle breeze|
|Sep||3.9||Barely noticeable||8.1||Gentle breeze|
|Oct||3.8||Barely noticeable||8.1||Gentle breeze|
|Nov||3.9||Barely noticeable||7.2||Gentle breeze|
|Dec||5||Light breeze||8.9||Gentle breeze|
Show Relative Humidity by Month
|Month||Avg. Relative Humidity|
Is it Safe to Travel to Eureka?
Our best data indicates this area is generally safe. As of Oct 07, 2019 there are no travel advisories or warnings for the United States; exercise normal security precautions. Check this page for any recent changes or regions to avoid: Travel Advice and Advisories. This advisory was last updated on Sep 23, 2019.
The Busiest and Least Crowded Months
The busiest month for tourism in Eureka, CA, US is July, followed by June and August. Prices for hotels and flights will be most expensive during these months, though you can save if you purchase well in advance. Tourists are unlikely to visit Eureka in December. Those willing to visit at these times will likely find it the least expensive month.
Estimated Tourism by Month
Most Popular Months to Visit
Overall Eureka Travel Experience by Season
Spring (March through May)
Humidity and temperatures combine to make this season feel moderately cold. Highs range from 60.3°F (15.7°C) and 55.3°F (12.9°C) with warmer temperatures in the later months. Rain is somewhat common with 3 to 12 days of significant precipitation per month. Spring is the second busiest for tourism, which makes it a good time for those looking for things to do.
Summer (June through August)
The middle-year months have comfortably cool weather with high temperatures that are brisk. These months see the least precipitation with 0 to 2 days of precipitation per month. June – August is the busiest season for tourism in Eureka, so lodging and other accommodations may cost more than usual.
Fall (September through November)
Fall daily highs range from 67.2°F (19.6°C) and 57.7°F (14.3°C), which will feel chilly given the humidity and wind. It rains or snows a significant amount: 2 to 9 days per month. Tourism is the slowest during these months due to the weather, so hotels may be affordably priced.
Winter (December through February)
Weather is too cold this time of year in Eureka to be enjoyable for warm weather travelers. The average high during this season is between 57.4°F (14.1°C) and 53.3°F (11.8°C). On average, it rains or snows a fair amount: 8 to 13 times per month. These times of year are fairly slow with tourists.