Your September weather guide
HotWeather in Sousse in September
September is a good time to visit Sousse if you want hot days and a sea that is warm enough for swimming. Average daytime highs are around 31°C, nights stay near 21°C, and the sea averages 26°C. The catch is that this is still hot-weather territory, not a gentle autumn break, and some rain is likely. It suits travellers happy to slow down at midday rather than stay active throughout the day.
Long-term climate averages for Sousse, not a forecast · 1991-2020
Sousse, month by month
Your snapshot
At a glance
The useful details for Sousse.
- Average daytime high
- 30.6°C
- 9 in 10 days stay below 36°C
- Average night-time low
- 20.7°C
- coldest 10% of nights: 18°C or lower
- Compared with London
- +12.0°C
- London averages 18.6°C in September
- Sea temperature
- 26.1°C
- year to year: 26°C to 27°C
- Sunshine per day (est.)
- 8.0h
- 66% of 12.2 h of daylight
- Rainy days (1 mm+)
- 5
- 48 mm over the month
- Humidity
- 66%
- Days over 25°C
- 95%
- 55% over 30°C
- Record high 1991-2020
- 41.3°C
- 2014-09-22
- Record low 1991-2020
- 14.9°C
- 1997-09-27
- Flight from London
- ≈ 3 h 6 min
- 1910 km, short-haul (estimate for a direct flight)
Records are observed extremes within 1991-2020, not typical holiday conditions. Warm-day percentages are shares of days, not day counts.
How September compares
September is the 4th warmest month of the year in Sousse and ranks 9th of 134 destinations we compare for September - see where else is hot in September. Within Tunisia it is 1st of 3 (Tunisia in September). Against London's average high of 18.6°C in September, Sousse is 12.0°C warmer by day and 9.5°C warmer at night.
Daytime and night-time in September
The typical September day in Sousse peaks at 30.6°C, but that is an average: the warmest 10% of days reach 35.5°C or more. About 95% of days top 25°C and 1 in 2 pass 30°C. Nights average 20.7°C; one night in ten drops to 18.0°C or lower, so pack a layer for evenings. Between 1991 and 2020 the hottest September day here reached 41.3°C (2014-09-22) and the coldest night 14.9°C (1997-09-27).
Rain in September
Some rain (4-8 rainy days): about 5 days with 1 mm or more, 48 mm in total. Year to year it varies a lot - the wettest September was 1997 with 168 mm, the driest 1992 with 4 mm. Humidity averages 66%.
Sea temperature in September
The sea averages 26.1°C - warm enough to swim (22°c+). Depending on the year it ranges from 25.5°C to 26.8°C. For the warmest sea here, come in August (26.9°C).
Sunshine and daylight
Around 8.0 hours of sunshine a day (estimated from cloud cover), 12.2 hours of daylight: the sun rises about 06:00 and sets about 18:25 local time in mid-September. Average cloud cover is 35%.
Is September a good time to visit Sousse?
Yes - it is one of the better months: hot days, manageable rain and long sunny days. The best months for Sousse on our scoring are June, May, September; months averaging 25°C or more: May, Jun, Jul, Aug, Sep, Oct.
Expect proper heat, not just warm afternoons
Pack for summer: light, loose clothing, a sunhat and sun protection will be more useful than heavy layers. Days reach 30°C on 55% of occasions, while the hottest days can reach 35.5°C or more, so plan anything energetic for the cooler parts of the day and leave room for shade at midday. Humidity averages 66%, which can make the heat feel less comfortable if you are moving about. Evenings are generally warm enough for light clothing, though a light layer is sensible for cooler nights. If you dislike sustained heat, September may still feel too hot rather than comfortably mild.
Warm swimming water, with room for rain
The sea is a strong reason to choose September: at an average of 26.1°C, it is comfortably warm for swimming rather than something to brave briefly. Sunshine averages about 8 hours a day, giving you plenty of scope for time outdoors without needing to spend the hottest part of the day in direct sun. Rain is the compromise. There are about 5 rainy days during the month, so do not plan on an entirely dry holiday. Keep outdoor plans flexible and pack a light waterproof. The overall balance suits a swimming-focused trip well, provided you are happy to work around occasional wet weather rather than expect clear skies every day.
A little perspective
Sousse through the year
September is highlighted. See how it compares with the rest of the year.
| Month | Day | Night | Sea | Sun/day | Rain mm | Rainy days | Days 25°C+ |
|---|---|---|---|---|---|---|---|
| January | 16.7°C | 7.6°C | 15.8°C | 5.6 | 33 | 5 | 0% |
| February | 17.4°C | 7.7°C | 14.6°C | 6.3 | 27 | 5 | 3% |
| March | 20.2°C | 9.6°C | 14.8°C | 7.0 | 42 | 6 | 11% |
| April | 23.1°C | 11.9°C | 16.1°C | 7.7 | 25 | 5 | 27% |
| Maybest | 27.2°C | 15.2°C | 18.8°C | 9.0 | 15 | 3 | 72% |
| Junebest | 31.5°C | 18.9°C | 22.3°C | 11.2 | 6 | 2 | 97% |
| July | 34.6°C | 21.7°C | 25.4°C | 12.9 | 1 | 0 | 100% |
| August | 34.8°C | 22.5°C | 26.9°C | 11.5 | 9 | 2 | 100% |
| SeptemberSelectedbest | 30.6°C | 20.7°C | 26.1°C | 8.0 | 48 | 5 | 95% |
| October | 26.5°C | 17.3°C | 23.9°C | 6.4 | 50 | 7 | 65% |
| November | 21.5°C | 12.7°C | 21.1°C | 5.8 | 34 | 6 | 13% |
| December | 17.7°C | 9.0°C | 18.0°C | 5.5 | 34 | 6 | 1% |
Day = average daytime high, night = average night-time low, 1991-2020.Sun is hours per day; rainy days count 1 mm or more.
Day, night and sea
Monthly average temperatures, 1991-2020
- Day
- Night
- Sea
Best months here
On warmth, low rainfall and sunshine, start with these.
Keep exploring
Similar in September
Closest matches on daytime temperature, sea temperature and sunshine, in other countries.
A little more detail
Sousse in September FAQs
Plain answers, grounded in the averages.
Is Sousse hot in September?
Sousse is hot in September: the average daytime high is 30.6°C and nights average 20.7°C. About 95% of September days reach 25°C or more.
Can you swim in the sea in Sousse in September?
The sea around Sousse averages 26.1°C in September, which is warm enough for most people to swim comfortably. Between 1991 and 2020 it ranged from 26°C to 27°C depending on the year.
How much does it rain in Sousse in September?
Sousse sees about 5 rainy days (1 mm or more) and 48 mm of rain in a typical September. The wettest September between 1991 and 2020 was 1997 (168 mm) and the driest was 1992 (4 mm).
How sunny is Sousse in September?
Sousse gets around 8.0 hours of sunshine a day in September out of 12.2 hours of daylight (estimated from average cloud cover).
How does Sousse compare with the UK in September?
Sousse is on average 12.0°C warmer than London by day in September (30.6°C against 18.6°C).
What is the hottest September on record in Sousse?
Between 1991 and 2020 the hottest September day in Sousse reached 41.3°C on 2014-09-22, and the coldest night dropped to 14.9°C on 1997-09-27.
How much hotter is Sousse than London in September?
Sousse has an average daytime high of 30.6°C, compared with 18.6°C in London, a difference of 12°C. That is a substantial change: pack for hot summer weather rather than the layers you might normally wear at home.
How long is the flight from London?
The flight from London takes about 3 h 6 min, making Sousse a short-haul option. It is a practical choice if you want September heat and warm swimming water without a long-haul flight.
About these averages
ERA5-Land climate reanalysis via Open-Meteo (11 km grid) and NOAA Coral Reef Watch 5 km sea temperatures, 1991-2020
Averages computed from daily values at Sousse. Sea temperature from the nearest 5 km sea cell, 1.1 km from that point. Sunshine hours are estimated from average cloud cover.Records are the highest and lowest daily values in that 30-year period, not all-time records. These are climate averages, not a forecast for your trip. How we measure holiday weather
- Hot · 25°C+
- Warm · 20°C to below 25°C
- Mild · 15°C to below 20°C
- Cool · below 15°C