Santa Monica weather in September
Temperature, sea and sunshine in September: long-term averages from 30 years of weather data, not a forecast.
Holiday weather in September
Excellent
Best time to visit: June – October
What is the weather like in Santa Monica in September?
In September, Santa Monica is hot: daytime highs average 28 °C, and nights cool down to about 17 °C. The sea averages 20.1 °C – refreshing for a swim. With around 10 hours of sunshine a day, there is plenty of sun. It hardly ever rains. On about 8 days the thermometer climbs to 30 °C or more. All in all, September is an excellent month for a holiday in Santa Monica.
September compared
How the weather changes from August to October. Tap a month to open it.
| AugustAug | SeptemberSep | OctoberOct | |
|---|---|---|---|
| Score | 87 | 86 | 80 |
| Day | 29° | 28° | 25° |
| Night | 18° | 17° | 14° |
| Sea | 20° | 20° | 19° |
| Sun | 11 h | 10 h | 8 h |
| Rain days | 0 | 1 | 2 |
More details for September
- Daylight
- 12 h 26 min06:36 – 19:02
- UV index
- 8 · very highclear sky, noon (estimate)All months
- Muggy days
- 2 daysdew point 18 °C or moreAll months
- Wind
- 18 km/haverage daily peakAll months
- Cloud cover
- 28 %on averageAll months
- Hot days
- 8 days30 °C or moreAll months
- Time zone
- UTC−7America/Los_Angeles
How the score comes together
- Temperatureweight 35 %100 %
- Seaweight 25 %44 %
- Sunshineweight 20 %100 %
- Few rainy daysweight 20 %100 %
Each factor is rated from 0 to 100 % and weighted for the travel style “Sun, sea & sand”.
What to pack in September
- Swimwear
- Sunscreen
- Sunglasses & sun hat
- Light, breathable clothes
- Water bottle – drink plenty
Santa Monica in September: quick answers
Is Santa Monica hot in September?
Yes. In September, Santa Monica is hot: daytime highs average 28 °C and nights stay around 17 °C. On about 8 days the thermometer climbs to 30 °C or more.
Can you swim in Santa Monica in September?
Yes. In September the sea averages 20.1 °C – refreshing for a swim.
Does it rain much in Santa Monica in September?
It hardly ever rains.
Santa Monica month by month
The whole year in Santa MonicaAll destinations: USAWhere to go in SeptemberSea temperature in September
Climate averages 1996–2025, not a forecast. Data: Copernicus ERA5 / ERA5-Land via Open-Meteo.com (CC BY 4.0), NOAA OISST, WMO 1991–2020 (NOAA NCEI), GeoNames (CC BY 4.0). Sources & licences