Cassis 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
Good
Best time to visit: July – August
What is the weather like in Cassis in September?
In September, Cassis is warm: daytime highs average 23 °C, and nights cool down to about 18 °C. The sea averages 21.7 °C – refreshing for a swim. The sun shines for around 9 hours a day. Rain falls on about 6 days, adding up to 68 mm. All in all, September is a good month for a holiday in Cassis.
September compared
How the weather changes from August to October. Tap a month to open it.
| AugustAug | SeptemberSep | OctoberOct | |
|---|---|---|---|
| Score | 97 | 79 | 40 |
| Day | 27° | 23° | 20° |
| Night | 21° | 18° | 15° |
| Sea | 23° | 22° | 20° |
| Sun | 11 h | 9 h | 6 h |
| Rain days | 3 | 6 | 8 |
More details for September
- Daylight
- 12 h 34 min07:16 – 19:50
- UV index
- 6 · highclear sky, noon (estimate)All months
- Muggy days
- 5 daysdew point 18 °C or moreAll months
- Wind
- 19 km/haverage daily peakAll months
- Cloud cover
- 40 %on averageAll months
- Hot days
- 0 days30 °C or moreAll months
- Time zone
- UTC+2Europe/Paris
How the score comes together
- Temperatureweight 35 %73 %
- Seaweight 25 %67 %
- Sunshineweight 20 %97 %
- Few rainy daysweight 20 %84 %
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
Cassis in September: quick answers
Is Cassis hot in September?
Warm rather than hot: in September, daytime highs in Cassis average 23 °C and nights cool to about 18 °C.
Can you swim in Cassis in September?
Yes. In September the sea averages 21.7 °C – refreshing for a swim.
Does it rain much in Cassis in September?
Rain falls on about 6 days, adding up to 68 mm.
Cassis month by month
The whole year in CassisAll destinations: FranceWhere 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