September weather forecastRohnert Park, CA
September
Weather in September
September, the first month of the autumn in Rohnert Park, is also a moderately hot month, with an average temperature varying between 55°F (12.8°C) and 79.3°F (26.3°C).Temperature
The average high-temperature for September is a still warm 79.3°F (26.3°C), closely aligning with the temperature of the preceding month. Despite a significant disparity with daytime temperatures, an average low-temperature of 55°F (12.8°C) is recorded during September.Humidity
The least humid month in Rohnert Park is September, with an average relative humidity of 62%.Rainfall
The months with the least rainfall are June through September Rain falls for 1.7 days and accumulates 0.04" (1mm) of rain.Daylight
In September, the average length of the day is 12h and 25min.On the first day of the month, sunrise is at 6:41 am and sunset at 7:40 pm. On the last day of September, in Rohnert Park, sunrise is at 7:06 am and sunset at 6:54 pm PDT.
Sunshine
In Rohnert Park, the average sunshine in September is 11h.UV index
In September, the average daily maximum UV index is 5. A UV Index estimate of 3 to 5 represents a medium vulnerability from exposure to the Sun's UV rays for average individuals.Note: A daily maximum UV index of 5 in September translates into the following instructions:
Exercise prevention - Precautions against solar damage are endorsed. It's crucial to reduce time in the direct Sun around mid-day due to the intense solar radiation. For effective sun eye protection, rely on sunglasses certified for UVA and UVB resistance.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Rohnert Park, CA
- Average high temperature in September: 79.3°F
The warmest months (with the highest average high temperature) are July and August (79.9°F).
The month with the lowest average high temperature is December (55.6°F).
- Average low temperature in September: 55°F
The months with the highest average low temperature are August and September (55°F).
The coldest month (with the lowest average low temperature) is December (42.4°F).
Average pressure in September
Rohnert Park, CA
- Average pressure in September: 29.92"Hg
The month with the highest atmospheric pressure is January (30.13"Hg).
The months with the lowest atmospheric pressure are June, August and September (29.92"Hg).
Average wind speed in September
Rohnert Park, CA
- Average wind speed in September: 5mph
The windiest month (with the highest average wind speed) is May (6.8mph).
The calmest month (with the lowest average wind speed) is November (4.7mph).
Average humidity in September
Rohnert Park, CA
- Average humidity in September: 62%
The month with the highest relative humidity is March (77%).
The month with the lowest relative humidity is September (62%).
Average rainfall in September
Rohnert Park, CA
- Average rainfall in September: 0.04"
The wettest month (with the highest rainfall) is February (0.91").
The driest months (with the least rainfall) are June, July, August and September (0.04").
Average rainfall days in September
Rohnert Park, CA
- Average rainfall days in September: 1.7 days
The month with the highest number of rainy days is March (8.7 days).
The month with the least rainy days is August (0.5 days).
Average daylight in September /
Average sunshine in September
Rohnert Park, CA
- Average daylight in September: 12h and 24min
The month with the longest days is June (Average daylight: 14h and 48min).
The month with the shortest days is December (Average daylight: 9h and 30min).
- Average sunshine in September: 11h and 0min
The month with the most sunshine is July (Average sunshine: 11h and 54min).
The month with the least sunshine is December (Average sunshine: 5h and 42min).
Average sunshine days in September
Rohnert Park, CA
- Average sunshine days in September: 27.5 days
The month with the most sunshine days is June (27.7 days).
The month with the least sunshine days is March (20.8 days).
Average UV index in September
Rohnert Park, CA
- Average UV index in September: 5
The month with the highest UV index is June (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 3).
Average cloud cover in September
Rohnert Park, CA
- Average cloud cover in September: 10
The month with the most cloud cover is March (Cloud cover 38).
The month with the least cloud cover is July (Cloud cover 9).
Average visibility in September
Rohnert Park, CA
- Average visibility in September: 6mi
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
