What September feels like in Colombo
September falls in Colombo's wet season — the rainfall numbers rise clearly above the dry months. Expect proper heat in the afternoon — slow down between noon and four. The gap between afternoon and night is small, so nights stay warm and the temperature hardly changes after dark. Thick, humid air means clothes cling and the heat feels stronger than the number.
Rain in Colombo in September
Rain is part of normal life this month, falling on most days. When rain comes it is heavy, about 9.8 mm (0.4 in) per wet day, often in short, strong bursts. The yearly figure is similar, around 10 mm per wet day.
Daylight and sunshine in September
In mid-September, sunrise is at about 6:01 am and sunset at about 6:11 pm (local time) — 12 h 10 min of daylight. Compared with mid-August, the day has lost 11 min. Close to the equator, sunrise and sunset times move very little through the year. Measured sunshine covers about 74% of the daylight — there are plenty of bright spells.
How September compares to the rest of the year
September is the 2nd coolest month of the year in Colombo. It is about as warm as August, with 37 mm more rain. Temperatures barely move from one month to the next here. The next month's average high: 28.8°C (83.8°F).
Who September suits
- Sightseeing: less ideal — rain falls on more than half the days.
- Parks & outdoor: less ideal — afternoons are too warm to linger outside.
- Beach: less ideal — too many rainy days.
- Museums & indoor: a good choice — with rain on most days, galleries and museums make easy plans.
Tips for visiting Colombo in September
Rain Protection
Keep a small umbrella in your bag and wear shoes that cope with puddles.
Sun Protection
Sunscreen, a hat and sunglasses; light breathable clothes.
Quick questions
How warm is Colombo in September?
Expect around 28.5°C (83.3°F) in the afternoon and 24.6°C (76.3°F) at night, which most visitors would call hot.
Does it rain a lot in Colombo in September?
It does: about 28 rainy days bring roughly 274 mm, so plan some indoor options.
What should I wear in Colombo in September?
The numbers point to rain protection and sun protection. Evenings feel similar to the day, so the same clothes work from morning to night.
Is September or October better for visiting Colombo?
September, narrowly: it ranks #7 of 12 among Colombo's months, against #8 for the other.