September weather forecastDelduwa, Sri Lanka
September weather forecast for Delduwa, Sri Lanka: The first month of the autumn, September, is also a moderately hot month in Delduwa, Sri Lanka, with an average temperature varying between 28.3°C (82.9°F) and 25.8°C (78.4°F). The average heat index, which represents the influence of relative humidity on air temperature, in September is estimated at 33°C (91.4°F).
September
Weather in September
The first month of the autumn, September, is also a moderately hot month in Delduwa, Sri Lanka, with an average temperature varying between 28.3°C (82.9°F) and 25.8°C (78.4°F).Temperature
August and September represent the coldest period, with an average high-temperature of 28.3°C (82.9°F).Heat index
September's average heat index is estimated at a hot 33°C (91.4°F). Exercise enhanced safety steps, heat cramps and heat exhaustion are probable. Heatstroke could be a result of sustained activity.It is worth noting that heat index values are gauged for conditions in the shade and light breezes. The heat index has the possibility to be enhanced by 15 Fahrenheit (8 Celsius) degrees when there is direct sun exposure.
Note: The heat index, also known as 'felt air temperature' or 'apparent temperature', gauges the sensation of temperature factoring in the air's moisture content. The impact of weather is individual, with diverse individuals experiencing it differently due to variations in body mass, height, and activity levels. Always consider that direct sunlight exposure might heighten the heat's effects, pushing the heat index up by 15 Fahrenheit (8 Celsius) degrees. Heat index values are essentially critical for children. Children often overlook the necessity for resting and fluid replenishment. Thirst is a late sign of dehydration - thus, it is critical to stay hydrated, especially during extended periods of physical activities.
Humidity
June and September, with an average relative humidity of 82%, are the most humid months.Rainfall
In Delduwa, Sri Lanka, in September, during 24.5 rainfall days, 222mm (8.74") of precipitation is typically accumulated. Throughout the year, there are 286.9 rainfall days, and 1974mm (77.72") of precipitation is accumulated.Daylight
The average length of the day in September is 12h and 9min.On the first day of September in Delduwa, sunrise is at 06:02 and sunset at 18:16. On the last day of the month, sunrise is at 05:57 and sunset at 18:01 +0530.
Sunshine
In Delduwa, the average sunshine in September is 8.5h.UV index
May and September, with an average maximum UV index of 6, are months with the lowest UV index. A UV Index value of 6 to 7 symbolizes a high health hazard from exposure to the Sun's UV rays for the ordinary person.Note: The average daily UV index of 6 in September transforms into the following instructions:
Apply measures and align with sun safety principles. Safeguarding against skin and eye injury is pivotal. Seek shade and limit direct Sun exposure between 10 a.m. and 4 p.m., when UV radiation is at its peak, but be aware that not all shade structures provide complete sun protection. Loose clothes with a tight weave are optimal for safeguarding yourself against the Sun's rays.
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Delduwa, Sri Lanka
- Average high temperature in September: 28.3°C
The warmest months (with the highest average high temperature) are March and April (30.3°C).
The months with the lowest average high temperature are August and September (28.3°C).
- Average low temperature in September: 25.8°C
The month with the highest average low temperature is May (26.7°C).
The coldest month (with the lowest average low temperature) is January (24°C).
Average pressure in September
Delduwa, Sri Lanka
- Average pressure in September: 1010.2mbar
The month with the highest atmospheric pressure is January (1011.4mbar).
The month with the lowest atmospheric pressure is May (1008.9mbar).
Average wind speed in September
Delduwa, Sri Lanka
- Average wind speed in September: 17.3km/h
The windiest month (with the highest average wind speed) is June (20.2km/h).
The calmest month (with the lowest average wind speed) is January (7.8km/h).
Average humidity in September
Delduwa, Sri Lanka
- Average humidity in September: 82%
The months with the highest relative humidity are June and September (82%).
The months with the lowest relative humidity are February and March (77%).
Average rainfall in September
Delduwa, Sri Lanka
- Average rainfall in September: 222mm
The wettest month (with the highest rainfall) is May (302mm).
The driest month (with the least rainfall) is January (38mm).
Average rainfall days in September
Delduwa, Sri Lanka
- Average rainfall days in September: 24.5 days
The month with the highest number of rainy days is June (28 days).
The month with the least rainy days is January (14.8 days).
Average daylight in September /
Average sunshine in September
Delduwa, Sri Lanka
- Average daylight in September: 12h and 12min
The month with the longest days is June (Average daylight: 12h and 30min).
The month with the shortest days is December (Average daylight: 11h and 48min).
- Average sunshine in September: 8h and 30min
The month with the most sunshine is April (Average sunshine: 9h and 18min).
The month with the least sunshine is December (Average sunshine: 7h and 0min).
Average sunshine days in September
Delduwa, Sri Lanka
- Average sunshine days in September: 2.4 days
The month with the most sunshine days is January (12.8 days).
The month with the least sunshine days is June (1 days).
Average UV index in September
Delduwa, Sri Lanka
- Average UV index in September: 6
The months with the highest UV index are January, February, March, April, June, July, August, October, November and December (UV index 7).
The months with the lowest UV index are May and September (UV index 6).
Average cloud cover in September
Delduwa, Sri Lanka
- Average cloud cover in September: 50
The month with the most cloud cover is June (Cloud cover 51).
The month with the least cloud cover is February (Cloud cover 26).
Average visibility in September
Delduwa, Sri Lanka
- Average visibility in September: 9km
The months with the highest visibility are January, February, March, April, June and December (10km).
The months with the lowest visibility are May, July, August, September, October and November (9km).





