September weather forecastPacifica, CA
September
Weather in September
The first month of the autumn, September, is still a refreshing month in Pacifica, California, with an average temperature varying between 67.5°F (19.7°C) and 56.8°F (13.8°C).Temperature
September brings the highest temperatures, with an average high of 67.5°F (19.7°C) and an average low of 56.8°F (13.8°C).Humidity
In September, the average relative humidity in Pacifica is 77%.Rainfall
The months with the least rainfall are June, July and September Rain falls for 3.6 days and accumulates 0.12" (3mm) of rain.Daylight
In Pacifica, 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 6:53 pm PDT.
Sunshine
In Pacifica, California, the average sunshine in September is 10.5h.UV index
The months with the highest UV index are June, August and September, with an average maximum UV index of 5. A UV Index reading of 3 to 5 represents a moderate threat to health from exposure to the Sun's UV rays for the ordinary person.Note: In September, a regular UV index of 5 translates into these guidelines:
Exercise prudence. Persons with fair skin could be burned in under 30 minutes. The best time to avoid the Sun's harmful UV radiation is during midday when it's most potent. To best shield against UV radiation, choose sun-safe garments and dependable sunglasses.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Pacifica, CA
- Average high temperature in September: 67.5°F
The warmest month (with the highest average high temperature) is September (67.5°F).
The month with the lowest average high temperature is December (55.6°F).
- Average low temperature in September: 56.8°F
The month with the highest average low temperature is September (56.8°F).
The coldest months (with the lowest average low temperature) are January and February (48.7°F).
Average pressure in September
Pacifica, CA
- Average pressure in September: 29.92"Hg
The month with the highest atmospheric pressure is January (30.13"Hg).
The month with the lowest atmospheric pressure is September (29.92"Hg).
Average wind speed in September
Pacifica, CA
- Average wind speed in September: 6.8mph
The windiest month (with the highest average wind speed) is April (9.4mph).
The calmest months (with the lowest average wind speed) are August and September (6.8mph).
Average humidity in September
Pacifica, CA
- Average humidity in September: 77%
The month with the highest relative humidity is August (82%).
The months with the lowest relative humidity are November and December (72%).
Average rainfall in September
Pacifica, CA
- Average rainfall in September: 0.12"
The wettest month (with the highest rainfall) is February (1.34").
The driest months (with the least rainfall) are June, July and September (0.12").
Average rainfall days in September
Pacifica, CA
- Average rainfall days in September: 3.6 days
The month with the highest number of rainy days is March (10.5 days).
The month with the least rainy days is September (3.6 days).
Average daylight in September /
Average sunshine in September
Pacifica, CA
- Average daylight in September: 12h and 24min
The month with the longest days is June (Average daylight: 14h and 42min).
The month with the shortest days is December (Average daylight: 9h and 36min).
- Average sunshine in September: 10h and 30min
The month with the most sunshine is July (Average sunshine: 11h and 6min).
The month with the least sunshine is December (Average sunshine: 5h and 42min).
Average sunshine days in September
Pacifica, CA
- Average sunshine days in September: 22.6 days
The month with the most sunshine days is October (24.5 days).
The month with the least sunshine days is August (18.7 days).
Average UV index in September
Pacifica, CA
- Average UV index in September: 5
The months with the highest UV index are June, August and September (UV index 5).
The months with the lowest UV index are February and December (UV index 3).
Average cloud cover in September
Pacifica, CA
- Average cloud cover in September: 21
The month with the most cloud cover is March (Cloud cover 39).
The months with the least cloud cover are September and October (Cloud cover 21).
Average visibility in September
Pacifica, 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).
