World Resorts Sri Lanka Negombo Weather

Negombo weather in September

Weather in Negombo: September

Average day temperature: 85.0°F
Average night temperature: 78.7°F
Sea water temperature: 82.7°F
Number of sunny days: 2 days
Day length: 12.1 - 12.2 hours
Number of rainy days: 13 days
Precipitation totals: 9.7 in.

Air temperature in September, °F

Show year:
2025
2024
2023

The highest day temperature during September of 2025 was 84°F. At the same time the lowest night temperature was 78°F. Daily and nightly averages during September were 82.2°F and 78.9°F.

Sea water temperature in Negombo in September, °F

Show year:
2025
2024
2023

The average sea water temperature in September of 2025 was 83.6°F. The highest and lowest sea temperatures during the month were 84.4°F and 82.2°F.

Sunny, partly cloudy and cloudy days

Mostly all days in September are cloudy but sunny and partly cloudy days are also possible.

Precipitation total in September, in.

Precipitation total value in Negombo in September is 11.7 in. It makes september one of the most rainy months of the year.

Wind speed in September, mph

The average wind speed value in September is 11.1 mph It makes September one of the most windy months of the year.

Average sunny hours

This chart shows average number of hours during the day when sunlight can reach the ground. It depends on day length and cloudiness during the day. The average number of sunny hours in September is: 4.0.

Best time for vacation in Negombo

Sunniest months:
February 19 days
January 18 days
March 16 days
Warmest months:
April 89.9 °F
March 89.9 °F
February 88.9 °F
Warmest sea temp:
April 86.4 °F
May 85.4 °F
March 84.9 °F
Coldest months:
August 85.0 °F
September 85.0 °F
July 85.1 °F
Rainiest months:
June 15 days
October 14 days
July 14 days
Windiest months:
June 13.1 mph
July 12.6 mph
August 12.3 mph

Negombo on a weather map

Negombo
+82°F
E 7 mph
Feels like: +88°F
Precip.: 86%
Places in Sri Lanka:
Name
°F
+86°F
+82°F
+82°F
+86°F
+86°F
+82°F
+82°F
+86°F
+82°F
+81°F
+86°F
+81°F
+86°F
+82°F
+86°F
24 Hours Forecast
Negombo
Local time: 11:40
December 05, friday
1200
82°F
E
7 mph
1500
81°F
E
11 mph
1800
81°F
S
9 mph
2100
77°F
SW
11 mph
December 06, saturday
0000
77°F
SW
8 mph
0300
75°F
SW
9 mph
0600
75°F
SW
9 mph
0900
81°F
SW
7 mph
Units of measurement: °C / °F