Trincomalee Weather in September
September in Trincomalee brings very high temperatures, with highs of 33°C (91°F) and nights dropping to 26°C (79°F). Rainfall is on the higher side this month, averaging around 67 mm (2.6 in), so keep a rain jacket handy.
Rainfall in Trincomalee in September
You can expect rain on around 6 days based on historical patterns, with 67 mm (2.6 in) average for the month. The rain this month typically falls in concentrated bursts rather than all-day showers. Expect a few heavier spells rather than constant grey skies.
Temperature in Trincomalee in September
If you're visiting Trincomalee in September, expect highs of 33°C (91°F) and overnight lows around 26°C (79°F). The hottest part of the day is usually in the afternoon, so lighter clothing can help you stay comfortable. With overnight lows of 26°C (79°F), nights stay very warm. Air conditioning makes a real difference if you're sensitive to heat. A cold shower before bed can also help you get to sleep more comfortably.
Sunshine in Trincomalee in September
The days are predominantly sunny, with an estimated total of around 234 hours of sunshine. These sun-filled days are perfect for playing sports, visiting parks, or going for a bike ride.
Wind Speed in Trincomalee in September
Wind speeds average 3 m/s (6 knots) during September. At this speed, light breezes keep leaves and small twigs in gentle motion while the wind also provides natural cooling. Since this is an average, some days are more tranquil while others have more persistent light winds that are more noticeable.
Average water temperature in September
The water temperature is 28°C (82°F), which most people find very comfortable. A good month for swimming and water sports.Our weather planner can help you find worldwide destinations with pleasant weather during this period. February typically offers the best weather for Trincomalee.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit Sri Lanka, check out our Trincomalee's climate page.
Trincomalee Temperature in September
Min Temperature
26°C (79°F)
Max Temperature
33°C (91°F)
Water Temperature
28°C (82°F)
Chance of Rain
21%
Precipitation
67 mm (2.6 in)
Rainy days
6 days
Humidity
63%
Windspeed
3 m/s (6 knots)
Sunshine
234 hours
Percentage Sunshine
Daily Historical Temperatures
31-year average (1985-2025)
Based on our historical records, temperatures in Trincomalee typically stay consistent throughout September, with daily highs averaging around 33°C (91°F). Nights are warm, with lows around 26°C (79°F).
Average temperatures in September
Daily Historical Precipitation
31-year average (1985-2025)
Average daily rainfall for each day of the month based on long-term records.
Average precipitation in September
Historical weather for Trincomalee in September
Browse day-by-day weather records for Trincomalee spanning 51 years. Select any month and year to see actual temperatures, rainfall, and conditions recorded on each day.
Trincomalee historical weather extremes in September
The extremes listed below come from historical weather data collected in Trincomalee from 2005 through 2025.
- On September 5, 2012, temperatures climbed to 39°C (102°F), marking the warmest September day on record.
- On September 25, 2019, Trincomalee saw its coldest September day with temperatures maxing out at 29°C (84°F).
- Nighttime temperatures dropped to 22°C (72°F) on September 23, 2021, marking the coldest September night on record.
Best Places in Sri Lanka in September
Find out more about the weather in Sri Lanka and which places have the best travel conditions in this month. See all of Sri Lanka in September →
perfect weather
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tolerable
unpleasant
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What to Wear in Trincomalee in September
Hot weather in September means keeping cool is the priority. Loose-fitting clothes in natural fabrics work best. Pack plenty of shorts, tank tops, and breathable shirts. Don't forget a hat, swimwear, and comfortable sandals. Rain gear is recommended, you can expect wet weather on multiple days. With water temperatures around 28°C (82°F), swimming conditions are excellent. Pack your swimsuit, goggles, and maybe some water shoes. And with plenty of sunshine hours, don’t forget sunglasses, sunscreen, and maybe a sun hat.What To Do in Trincomalee in September
We rated the following activities from 1 (least suitable) to 10 (best) to do.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit Sri Lanka, check out our Trincomalee's climate page.
Temperature Rainfall Sunshine Humidity Wind Speed Water Temp
See the full Trincomalee climate overview or explore weather in Sri Lanka.
