Contents
- Weather in September
- Frequently asked questions
- Average temperature in September
- Average pressure in September
- Average wind speed in September
- Average humidity in September
- Average rainfall in September
- Average rainfall days in September
- Average sea temperature in September
- Average daylight in September
- Average sunshine in September
- Average sunshine days in September
- Average UV index in September
- Average cloud cover in September
- Average visibility in September
Weather in September
Temperature
September's onset records a minor alteration in the average high-temperature to a still moderately hot 80.2°F (26.8°C) from August's 80.8°F (27.1°C). Nighttime temperature lowers to an average of 63.7°F (17.6°C) in September.Humidity
In September, the average relative humidity is 61%.Rainfall
In September, the rain falls for 2.5 days. Throughout September, 0.16" (4mm) of precipitation is accumulated. In Santa Monica, during the entire year, the rain falls for 48.8 days and collects up to 7.52" (191mm) of precipitation.Ocean temperature
August through October, with an average ocean temperature of 66.2°F (19°C), are months with the warmest seawater.Note: For most, swimming in 66.2°F (19°C) is not an enjoyable activity. Furthermore, controlling your breathing becomes progressively more difficult as the water temperature decreases from 69.8°F (21°C) to 59°F (15°C).
Daylight
In September, the average length of the day is 12h and 22min.On the first day of September, sunrise is at 6:28 am and sunset at 7:19 pm. On the last day of the month, sunrise is at 6:48 am and sunset at 6:39 pm PDT.
Sunshine
In Santa Monica, the average sunshine in September is 10.5h.UV index
June through September, with an average maximum UV index of 6, are months with the highest UV index in Santa Monica. A UV Index estimate of 6 to 7 represents a high health hazard from unsafe exposure to UV radiation for ordinary individuals.Note: A maximum UV index of 6 in September translates into the following recommendations:
Prevent overexposure. Protection from the sun's harmful effects is needed. Stay in the shade and limit direct sun exposure between 10 a.m. and 4 p.m., when UV radiation is at its strongest. Remember, however, that not all shade structures provide full sun protection. A wide-brim hat offers excellent sun protection for the eyes, ears, face, and neck. Sunglasses with UVA and UVB protection significantly reduce eye damage from sun exposure.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the temperature in September?
What is the average humidity in September?
How many days does it rain in September?
What months are the ocean warmest?
What is the ocean temperature in September?
What is the average length of the day in September?
When is the sunrise / sunset in September in Santa Monica?
How long on average sun shines in September?
What is the month with the highest UV index?
How high is the UV index in September?
Average temperature in September
Santa Monica, CA
- Average high temperature in September: 80.2°F
The warmest month (with the highest average high temperature) is August (80.8°F).
The month with the lowest average high temperature is December (63.9°F).
- Average low temperature in September: 63.7°F
The month with the highest average low temperature is August (64.4°F).
The coldest month (with the lowest average low temperature) is February (50.5°F).
Average pressure in September
Santa Monica, CA
- Average pressure in September: 29.9"Hg
The month with the highest atmospheric pressure is January (30.1"Hg).
The months with the lowest atmospheric pressure are June and September (29.9"Hg).
Average wind speed in September
Santa Monica, CA
- Average wind speed in September: 4.8mph
The windiest month (with the highest average wind speed) is April (6.3mph).
The calmest months (with the lowest average wind speed) are August and September (4.8mph).
Average humidity in September
Santa Monica, CA
- Average humidity in September: 61%
The month with the highest relative humidity is June (69%).
The month with the lowest relative humidity is November (52%).
Average rainfall in September
Santa Monica, CA
- Average rainfall in September: 0.16"
The wettest month (with the highest rainfall) is January (1.54").
The driest months (with the least rainfall) are June and August (0.08").
Average rainfall days in September
Santa Monica, CA
- Average rainfall days in September: 2.5 days
The month with the highest number of rainy days is March (6.8 days).
The month with the least rainy days is August (1.8 days).
Average sea temperature in September
Santa Monica, CA
- Average sea temperature in September: 66°F
The best months for swimming (with the highest average sea temperature) are August, September and October (66°F).
The coldest months (with the lowest average sea temperature) are January, February, March, April, May and December (59°F).
Average daylight in September /
Average sunshine in September
Santa Monica, CA
- Average daylight in September: 12h and 2min
The month with the longest days is June (Average daylight: 14h and 24min).
The month with the shortest days is December (Average daylight: 9h and 54min).
- Average sunshine in September: 10h and 3min
The months with the most sunshine are July and August (Average sunshine: 11h and 54min).
The months with the least sunshine are February and December (Average sunshine: 6h and 36min).
Average sunshine days in September
Santa Monica, CA
- Average sunshine days in September: 26.3 days
The month with the most sunshine days is August (27.9 days).
The month with the least sunshine days is February (21.8 days).
Average UV index in September
Santa Monica, CA
- Average UV index in September: 6
The months with the highest UV index are June, July, August and September (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 4).
Average cloud cover in September
Santa Monica, CA
- Average cloud cover in September: 12
The months with the most cloud cover are March and December (Cloud cover 23).
The month with the least cloud cover is August (Cloud cover 8).
Average visibility in September
Santa Monica, 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).
Santa Monica, California, USA
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