September weather forecastLarkspur, CA
September
Weather in September
September, the first month of the autumn in Larkspur, is still a pleasant month, with an average temperature varying between 56.1°F (13.4°C) and 72.3°F (22.4°C).Temperature
The warmest period tends to be September, when average temperatures fluctuate between a high of 72.3°F (22.4°C) and a low of 56.1°F (13.4°C).Humidity
In September, the average relative humidity is 71%.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
The average length of the day in September is 12h and 25min.On the first day of September, sunrise is at 6:40 am and sunset at 7:38 pm. On the last day of the month, sunrise is at 7:05 am and sunset at 6:54 pm PDT.
Sunshine
In September, the average sunshine is 10.4h.UV index
The months with the highest UV index are April, June through September, with an average maximum UV index of 5. A UV Index reading of 3 to 5 represents a medium health hazard from unsafe exposure to UV radiation for the ordinary person.Note: In September, a daily UV index of 5 turns into the following recommendations:
Take heed. Individuals of lighter complexion can be burned in less than half an hour. Solar radiation is at its peak intensity during midday, so it's advisable to stay indoors or in the shade. Outfit yourself in sun-safe attire, like long sleeves, pants, a hat, and UV-blocking sunglasses.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Larkspur, CA
- Average high temperature in September: 72.3°F
The warmest month (with the highest average high temperature) is September (72.3°F).
The month with the lowest average high temperature is December (55.4°F).
- Average low temperature in September: 56.1°F
The month with the highest average low temperature is September (56.1°F).
The coldest month (with the lowest average low temperature) is December (45.3°F).
Average pressure in September
Larkspur, 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
Larkspur, CA
- Average wind speed in September: 5.9mph
The windiest month (with the highest average wind speed) is May (7.8mph).
The calmest months (with the lowest average wind speed) are October and November (5.5mph).
Average humidity in September
Larkspur, CA
- Average humidity in September: 71%
The month with the highest relative humidity is March (77%).
The month with the lowest relative humidity is October (68%).
Average rainfall in September
Larkspur, CA
- Average rainfall in September: 0.04"
The wettest month (with the highest rainfall) is February (0.87").
The driest months (with the least rainfall) are June, July, August and September (0.04").
Average rainfall days in September
Larkspur, CA
- Average rainfall days in September: 1.7 days
The month with the highest number of rainy days is March (8.8 days).
The months with the least rainy days are June and August (1.2 days).
Average daylight in September /
Average sunshine in September
Larkspur, 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 36min).
- Average sunshine in September: 10h and 24min
The month with the most sunshine is July (Average sunshine: 11h and 12min).
The month with the least sunshine is December (Average sunshine: 5h and 30min).
Average sunshine days in September
Larkspur, CA
- Average sunshine days in September: 26 days
The month with the most sunshine days is June (26.4 days).
The month with the least sunshine days is March (20.7 days).
Average UV index in September
Larkspur, CA
- Average UV index in September: 5
The months with the highest UV index are April, June, July, August and September (UV index 5).
The months with the lowest UV index are January, February, November and December (UV index 3).
Average cloud cover in September
Larkspur, CA
- Average cloud cover in September: 19
The month with the most cloud cover is March (Cloud cover 39).
The month with the least cloud cover is September (Cloud cover 19).
Average visibility in September
Larkspur, 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).
