Beau Fixe
Mannar

🇱🇰 Sri Lanka · Indian Ocean

Mannar weather in September

Ideal — one of the best times of year

Afternoon
29.9 °C
Night
26.8 °C
Sea temperature
28.6 °C
Rainy days
9 days
Relative humidity
79 %

100% of days reached 25 °C over the last 10 years

📷 Amith Anuradha · Pexels

Month by month

MonthAfternoonSeaRainVerdict
January28.7 °C27.4 °C10 daysIdeal — one of the best times of year
February29.9 °C27.8 °C7 daysIdeal — one of the best times of year
March31.4 °C29.3 °C7 daysIdeal — one of the best times of year
April31.7 °C30.8 °C13 daysIdeal — one of the best times of year
May31 °C30.2 °C12 daysIdeal — one of the best times of year
June30.6 °C29.2 °C7 daysIdeal — one of the best times of year
July30.4 °C28.8 °C5 daysIdeal — one of the best times of year
August30 °C28.4 °C7 daysIdeal — one of the best times of year
September29.9 °C28.6 °C9 daysIdeal — one of the best times of year
October29.1 °C29 °C20 daysUnfavourable season
November28.3 °C28.9 °C24 daysUnfavourable season
December28.3 °C28 °C18 daysPossible, with trade-offs
Best months :JulyMarchAugust

Before you go

Three things to check once you have picked your dates.

Entry

Entry rules depend on your nationality and change often. Check them before booking.

Official entry requirements ↗

Safety

No specific restrictions

Usual precautions apply.

Official advice updated 26 May 2026

UK Foreign Office

Health

Recommended vaccinations, water quality, mosquitoes: advice depends on the country and the season. Some vaccines need time before departure.

Health advice ↗

Beau Fixe is not a safety or health authority. These notes summarise public advisories and link to their source; only the competent authorities are authoritative. Alert levels: Foreign, Commonwealth & Development Office (gov.uk), Open Government Licence v3.0.

FAQ

Can you swim in Mannar in September?

The sea averages 28.6°C in September — yes, pleasant swimming.

How hot is Mannar in September?

Expect 29.9°C in the afternoon and 26.8°C at night, averaged over the last 10 years.

Does it rain a lot in Mannar in September?

Around 9 days with rain (≥ 1 mm) in the month — 29% of days.

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