Monterey, California 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
Fair
Best time to visit: July – September
What is the weather like in Monterey, California in September?
In September, Monterey, California is warm: daytime highs average 22 °C, and nights cool down to about 14 °C. The sea averages 14.9 °C – swimming is only for the hardy. With around 9 hours of sunshine a day, there is plenty of sun. It hardly ever rains. All in all, September is a so-so month for a holiday in Monterey, California.
September compared
How the weather changes from August to October. Tap a month to open it.
| AugustAug | SeptemberSep | OctoberOct | |
|---|---|---|---|
| Score | 56 | 57 | 45 |
| Day | 22° | 22° | 20° |
| Night | 14° | 14° | 12° |
| Sea | 15° | 15° | 15° |
| Sun | 10 h | 9 h | 8 h |
| Rain days | 0 | 1 | 2 |
More details for September
- Daylight
- 12 h 28 min06:49 – 19:17
- UV index
- 7 · highclear sky, noon (estimate)All months
- Muggy days
- 0 daysdew point 18 °C or moreAll months
- Wind
- 13 km/haverage daily peakAll months
- Cloud cover
- 29 %on averageAll months
- Hot days
- 0 days30 °C or more
- Time zone
- UTC−7America/Los_Angeles
How the score comes together
- Temperatureweight 35 %48 %
- Seaweight 25 %0 %
- 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
- Sunscreen
- Sunglasses & sun hat
- A jumper for the evenings
Monterey, California in September: quick answers
Is Monterey, California hot in September?
Warm rather than hot: in September, daytime highs in Monterey, California average 22 °C and nights cool to about 14 °C.
Can you swim in Monterey, California in September?
Only if you don't mind cold water: in September the sea averages just 14.9 °C. Comfortable swimming temperatures are not reached at any time of year.
Does it rain much in Monterey, California in September?
It hardly ever rains.
Monterey, California month by month
The whole year in Monterey, CaliforniaAll 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