September weather forecastEureka, CA
September
Weather in September
September, the first month of the autumn in Eureka, is still a pleasant month, with an average temperature ranging between max 68.2°F (20.1°C) and min 52.3°F (11.3°C).Temperature
Eureka experiences a minor change to a still pleasant 68.2°F (20.1°C) in average high-temperature during September, closely reflecting August. During September, the temperature tends to dip to an average of 52.3°F (11.3°C) at night.Humidity
In Eureka, the average relative humidity in September is 77%.Rainfall
In Eureka, during September, the rain falls for 3.7 days and regularly aggregates up to 0.24" (6mm) of precipitation. Throughout the year, there are 77.3 rainfall days, and 8.58" (218mm) of precipitation is accumulated.Snowfall
January, March through December are months without snowfall.Daylight
In Eureka, California, the average length of the day in September is 12h and 27min.On the first day of September in Eureka, sunrise is at 6:44 am and sunset at 7:48 pm. On the last day of the month, sunrise is at 7:13 am and sunset at 6:59 pm PDT.
Sunshine
The average sunshine in September in Eureka is 10.3h.UV index
In September, the average daily maximum UV index is 4. A UV Index estimate of 3 to 5 represents a moderate threat to health from unsafe exposure to UV radiation for ordinary individuals.Note: The maximum daily UV index of 4 during September translates into the following directions:
Exercise care. People with light skin might get burns in fewer than 30 minutes. Avoiding direct sun during mid-day hours can prevent harmful UV radiation exposure. Fend off the sun's harsh rays with appropriate clothing, a wide-brim hat, and UV-protective sunglasses.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Eureka, CA
- Average high temperature in September: 68.2°F
The warmest month (with the highest average high temperature) is August (68.4°F).
The months with the lowest average high temperature are February and December (52.9°F).
- Average low temperature in September: 52.3°F
The month with the highest average low temperature is August (52.9°F).
The coldest month (with the lowest average low temperature) is February (42.4°F).
Average pressure in September
Eureka, CA
- Average pressure in September: 29.97"Hg
The month with the highest atmospheric pressure is January (30.13"Hg).
The month with the lowest atmospheric pressure is August (29.96"Hg).
Average wind speed in September
Eureka, CA
- Average wind speed in September: 6.5mph
The windiest month (with the highest average wind speed) is March (9mph).
The calmest month (with the lowest average wind speed) is August (6.2mph).
Average humidity in September
Eureka, CA
- Average humidity in September: 77%
The month with the highest relative humidity is March (82%).
The month with the lowest relative humidity is October (76%).
Average rainfall in September
Eureka, CA
- Average rainfall in September: 0.24"
The wettest month (with the highest rainfall) is December (1.73").
The driest month (with the least rainfall) is July (0.08").
Average rainfall days in September
Eureka, CA
- Average rainfall days in September: 3.7 days
The month with the highest number of rainy days is March (11.2 days).
The month with the least rainy days is August (1.7 days).
Average snowfall in September
Eureka, CA
- Average snowfall in September: 0"
The month with the highest snowfall is February (0.04").
The months with the least snowfall are January, March, April, May, June, July, August, September, October, November and December (0").
Average snowfall days in September
Eureka, CA
- Average snowfall days in September: 0 days
The months with the highest number of snowfall days are February and December (0.1 days).
The months with the least snowfall days are January, March, April, May, June, July, August, September, October and November (0 days).
Average daylight in September /
Average sunshine in September
Eureka, CA
- Average daylight in September: 12h and 24min
The month with the longest days is June (Average daylight: 15h and 6min).
The month with the shortest days is December (Average daylight: 9h and 18min).
- Average sunshine in September: 10h and 18min
The months with the most sunshine are July and August (Average sunshine: 11h and 36min).
The month with the least sunshine is December (Average sunshine: 5h and 12min).
Average sunshine days in September
Eureka, CA
- Average sunshine days in September: 25.6 days
The month with the most sunshine days is July (27.7 days).
The month with the least sunshine days is March (17.9 days).
Average UV index in September
Eureka, CA
- Average UV index in September: 4
The month with the highest UV index is July (UV index 5).
The months with the lowest UV index are January, February, March, November and December (UV index 3).
Average cloud cover in September
Eureka, CA
- Average cloud cover in September: 17
The month with the most cloud cover is March (Cloud cover 46).
The months with the least cloud cover are July and August (Cloud cover 16).
Average visibility in September
Eureka, CA
- Average visibility in September: 6mi
The months with the highest visibility are January, February, March, April, May, June, July, September, October, November and December (6mi).
The month with the lowest visibility is August (5mi).
