Weather in Colombo in October

Shoulder season. October sits in between. You will get good days and you will lose some. You should expect rain on 27 days of the month, which is more days wet than dry.

October ranks 6 of 12 in Colombo: past the worst of the year but short of January, which is the month to book if the dates are open.

Rain on 27 of the month's 31 days, 11 of them heavy. At that frequency a wet-weather backup is not a contingency, it is the itinerary — book the indoor things first and treat the clear days as the bonus. Natural fibres and a second shirt for the day. At 85% nothing dries, including you.

What the averages hide

Averages flatten a month, and this one hides a few things: 4 days top 30 °C — hot spells arrive, but they break; the day barely swings — 3.6 °C between the overnight low and the afternoon high. Across the twenty years measured, the hottest October day reached 32.7 °C and the coldest night fell to 22.9 °C, and the wettest single day dropped 63 mm — roughly 22% of the month's rain in one day.

October is statistically steady but not small: the year-to-year variation is modest in relative terms, yet the wettest October on record still delivered 509 mm against 104 mm in the driest. In a month this wet, even a tame spread is a lot of rain in absolute terms — the 292 mm average is a reasonable planning figure, not a promise.

Wind is light at 11.3 km/h, so the temperature on the page is close to the temperature on your skin, and humidity at 85% is the real story though — it is the number that decides how the day feels, not the 29 °C.

How October sits in the year

Temperatures hold steady either side: 29 °C in September, 29 here, 29.2 in November. Nothing about the timing within the month matters much. Rain has already shifted: 5 days more than September had.

Daylight in October

Colombo sits close enough to the equator that daylight barely moves all year — 12 hours in October, against a range of just 0.8 hours across the whole calendar. Sunrise and sunset land at roughly the same time whenever you come.

Sea temperature

The sea sits at about 28.4 °C in October — warm enough that the water offers no relief from the heat. The sea peaks at 29.9 °C in April and bottoms out at 27.2 °C — water lags the air by a month or two, which is why the best swimming often comes after the best weather.

How busy it gets

Quiet. Few other visitors, cheaper rooms, and a real chance some seasonal operators are shut.

Crowd levels are estimated from climate desirability and school-holiday calendars, not from visitor numbers.

October in Colombo versus nearby

If Colombo is one option among several, the nearby comparison is worth making. Kandy is close enough to be a coin toss — within a degree on temperature, 4 days less rain. Trincomalee is close enough to be a coin toss — within a degree on temperature, 5 days less rain.

So: October works, with January the better month by 13 points if the dates can move. If they cannot, nothing here should stop you booking.

Every month in Colombo

See all twelve months in Colombo, or where else to go in October.