Bissau 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: November – December
What is the weather like in Bissau in September?
In September, Bissau is hot: daytime highs average 29 °C, and even at night it stays warm at around 24 °C. The sea averages 28.4 °C – lovely and warm for swimming. Expect around 5 hours of sunshine a day. It is the rainy season: rain falls on about 27 days, totalling 335 mm. On about 8 days the thermometer climbs to 30 °C or more. The air is often humid and muggy. All in all, September is a so-so month for a holiday in Bissau.
September compared
How the weather changes from August to October. Tap a month to open it.
| AugustAug | SeptemberSep | OctoberOct | |
|---|---|---|---|
| Score | 45 | 42 | 38 |
| Day | 28° | 29° | 30° |
| Night | 24° | 24° | 25° |
| Sea | 28° | 28° | 29° |
| Sun | 4 h | 5 h | 6 h |
| Rain days | 29 | 27 | 22 |
More details for September
- Daylight
- 12 h 12 min06:52 – 19:04
- UV index
- 13 · extremeclear sky, noon (estimate)All months
- Muggy days
- 30 daysdew point 18 °C or moreAll months
- Wind
- 14 km/haverage daily peakAll months
- Cloud cover
- 83 %on averageAll months
- Hot days
- 8 days30 °C or moreAll months
- Time zone
- UTC+0Africa/Bissau
How the score comes together
- Temperatureweight 50 %74 %
- Sunshineweight 20 %25 %
- Few rainy daysweight 30 %0 %
Each factor is rated from 0 to 100 % and weighted for the travel style “City break”.
What to pack in September
- Swimwear
- Sunscreen
- Sunglasses & sun hat
- Light, breathable clothes
- Insect repellent
- Rain jacket or umbrella
Bissau in September: quick answers
Is Bissau hot in September?
Yes. In September, Bissau is hot: daytime highs average 29 °C and nights stay around 24 °C. On about 8 days the thermometer climbs to 30 °C or more.
Can you swim in Bissau in September?
Yes. In September the sea averages 28.4 °C – lovely and warm for swimming.
Does it rain much in Bissau in September?
It rains often – on about 27 days, adding up to 335 mm.
Bissau month by month
The whole year in BissauAll destinations: Guinea-BissauWhere 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