Kenya
Diani Beach in September: weather, sea & travel advice
This month's data profile
Sea conditions lead
Diani Beach in September is climatically well suited to beach holidays, family holidays and city breaks. The average daily high is around 29 °C, and the sea is about 26 °C. With about 6 rainy days it is moderate.
Historical monthly averages, not a weather forecast. Individual days and years can differ substantially.
Rank among 12 monthly averages
85/100 · #2
Warmth
#9
Dryness
#2
Sun
#7
Sea warmth
#11
Published best categories: Overall, Beach, City break, Active, Family
Diani Beach · SeptemberPhoto: Lebu Ayiga · CC BY 4.0Climate facts
- Average high
- 29 °C
- Average low
- 23 °C
- Sea
- 26 °C
- Rainy days (est.)
- 6 rainy days (est.)
- Sun (est.)
- 8 h/day
- Humidity
- 74 %
Climate evidence with direct month comparison
The highlighted row is the selected month. Precipitation total and rainy days are separate monthly averages.
| Month | Avg high °C | Avg low °C | Rainy days (est.) | Precipitation mm | Sun h/day (est.) | Humidity % | Wind m/s | Sea °C | Score |
|---|---|---|---|---|---|---|---|---|---|
| August | 28 | 23 | 7 | 28 | 6.7 | 75 | 4.6 | 25 | 87 |
| September (selected) | 29 | 23 | 6 | 39 | 7.5 | 74 | 4.3 | 26 | 85 |
| October | 30 | 24 | 11 | 72 | 7.8 | 74 | 3.6 | 27 | 74 |
How do the previous and next months compare?
Baseline: September (85/100)
Positive and negative values show the change from the selected month.
| Score Δ | Average high Δ | Average low Δ | Rainy days Δ | Rain Δ | Sun Δ | Humidity Δ | Wind Δ | Sea Δ | |
|---|---|---|---|---|---|---|---|---|---|
| August | +2 | -0.9 °C | -0.4 °C | +0.5 | -11.5 mm | -0.8 h | +0.6 % | +0.4 m/s | -0.3 °C |
| October | -11 | +1 °C | +0.8 °C | +4.3 | +33 mm | +0.3 h | +0.5 % | -0.6 m/s | +0.8 °C |
All twelve months in context

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Where to stay in Diani Beach
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Useful next decisions
Frequently asked questions
How warm is Diani Beach in September?
The average daily high is around 29 °C, with an average daily low of about 23 °C.
Can you swim in Diani Beach in September?
The sea is about 26 °C (warm).
Does it rain a lot in Diani Beach in September?
The curated estimate is about 6 rainy days per month, not a directly measured long-term average. Total precipitation averages around 39 mm for the month. A rainy day does not mean all-day rain.
When is the best time to visit Diani Beach?
By the climate score, June, July, August and September are the strongest months for Diani Beach. For a beach trip: July, August, September and October. September is one of them.