Nilaveli Weather in September

September in Nilaveli 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 68 mm (2.7 in), so keep a rain jacket handy.

Rainfall in Nilaveli in September

Historically, September sees about 6 days of rain, with a monthly average of 68 mm (2.7 in). 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 Nilaveli in September

In September, Nilaveli gets very high temperatures, with highs of 33°C (91°F). Nights cool to around 26°C (79°F). For most visitors, the main thing to prepare for is the heat during the day. With lows of 26°C (79°F), it stays warm throughout the night. A cold shower before going to sleep is one of the easiest ways to cool down before bed.

Sunshine in Nilaveli in September

Expect a lot of sunshine this month, with about 234 hours of sun. These sunny conditions add to the overall experience.

Wind Speed in Nilaveli in September

September has wind speeds averaging 3 m/s (6 knots). You can expect comfortable light winds that steadily move flags and feel mild throughout the day. Since this is an average, daily conditions vary from gentle winds to more active breezes.

Average water temperature in September

The water is 28°C (82°F) this month — warm enough that getting in requires no effort at all. Good conditions for swimming, snorkeling, or just floating around.

If you prefer dry days with pleasant temperatures, February typically offers the best circumstances. If you're seeking pleasant, dry and sunny weather somewhere else in the world, our weather planner can help you explore other options.

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Check the conditions for any month of the year.

• January
• February
• March
• April

• May
• June
• July
• August

• September
• October
• November
• December

For a detailed overview over the year and the best time to visit Sri Lanka, check out our Nilaveli's climate page.

Nilaveli Temperature in September

Min Temperature 26°C (79°F)  

Max Temperature 33°C (91°F)  

Water Temperature 28°C (82°F) *  

Chance of Rain 20%  

Precipitation 68 mm (2.7 in)  

Rainy days 6 days  

Humidity 63% *  

Windspeed 3 m/s (6 knots) *  

Sunshine 234 hours *  

Percentage Sunshine *  

* Data from: Trincomalee, Sri Lanka (14 KM, 8 Miles).

Daily Historical Temperatures

31-year average (1985-2025)

Based on our historical records, temperatures in Nilaveli 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

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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

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Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

‹ January February March April May June July August September October November December ›

Historical weather for Nilaveli in September

Browse day-by-day weather records for Nilaveli spanning 51 years. Select any month and year to see actual temperatures, rainfall, and conditions recorded on each day.

Historical weather Temperatures Precipitation

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‹ January February March April May June July August September October November December ›

Nilaveli historical weather extremes in September

Based on 21 years of weather observations in Nilaveli between 2004 and 2025, these are the recorded extremes.

• On September 5, 2012, temperatures climbed to 39°C (102°F), marking the warmest September day on record.
• Nilaveli experienced its chilliest September day on September 22, 2004, reaching only 25°C (77°F).
• Nilaveli registered its coldest September night on September 23, 2021, with temperatures dropping to 23°C (73°F).

What to Wear in Nilaveli in September

Get ready for hot weather in September! Lightweight, breathable fabrics are your best friend during this month. Cotton and linen shirts, shorts, sundresses, and sandals will keep you comfortable. Light colors help reflect the heat, avoid wearing black. Rain is likely on several days, so bring a good rain jacket. The water temperature sits at about 28°C (82°F), making it perfect for swimming and water activities. Don't forget to pack your favorite swimwear and perhaps some snorkel gear. You'll definitely want to pack sunglasses and sunscreen. There will be plenty of bright sunshine this month.

What To Do in Nilaveli in September

We rated the following activities from 1 (least suitable) to 10 (best) to do.

Swimming

9/10

Cycling

8/10

Walking

8/10

Camping

7/10

Outdoor sports

8/10

Select a Month

Check the conditions for any month of the year.

• January
• February
• March
• April

• May
• June
• July
• August

• September
• October
• November
• December

For a detailed overview over the year and the best time to visit Sri Lanka, check out our Nilaveli's climate page.

More climate data for Nilaveli

Temperature Rainfall Sunshine Humidity Wind Speed Water Temp

See the full Nilaveli climate overview or explore weather in Sri Lanka.