Contents
- Weather in September
- Frequently asked questions
- Average temperature in September
- Average pressure in September
- Average wind speed in September
- Average humidity in September
- Average rainfall in September
- Average rainfall days in September
- Average daylight in September
- Average sunshine in September
- Average sunshine days in September
- Average UV index in September
- Average cloud cover in September
- Average visibility in September
September
Weather in September
Temperature
August and September are characterised by lowest temperatures, with an average high of 28.3°C (82.9°F).Heat index
The heat index value for September is evaluated at a tropical 33°C (91.4°F). Exercise extra preventive actions, heat cramps and heat exhaustion are plausible. Continuous activity could result in heatstroke.Note that heat index values are valued for light wind and location in the shade. Direct sunlight might cause an increase of up to 15 Fahrenheit (8 Celsius) degrees in the heat index.
Note: The heat index, also known as 'real feel' or 'feels like', determines the feeling of heat when you account for the relative humidity. This impact is subjective, influenced by the person's physical activity and individual heat perception, affected by factors including wind, attire, and metabolic differences. Sunshine, when direct, has the potential to intensify weather effects, leading to an increase in the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are particularly relevant to babies and toddlers. Young people are generally more susceptible than adults because they perspire less. Furthermore, their proportionally larger skin surface to their petite bodies and the increased heat output from their actions add to the risk.
Humidity
The months with the highest humidity are June and September, with an average relative humidity of 82%.Rainfall
In Walahanduwa, Sri Lanka, during September, the rain falls for 24.5 days and regularly aggregates up to 222mm (8.74") of precipitation. Throughout the year, in Walahanduwa, there are 286.9 rainfall days, and 1974mm (77.72") of precipitation is accumulated.Daylight
The average length of the day in September in Walahanduwa is 12h and 9min.On the first day of September in Walahanduwa, sunrise is at 06:02 and sunset at 18:15. On the last day of the month, sunrise is at 05:56 and sunset at 18:01 +0530.
Sunshine
The average sunshine in September is 8.5h.UV index
The months with the lowest UV index are May and September, with an average maximum UV index of 6. A UV Index reading of 6 to 7 represents a high health vulnerability from exposure to the Sun's UV rays for the ordinary person.Note: A maximum high daily UV index of 6 during September translates into the following directions:
Shield from overexposure. Defense against sun-related harm is required. The Sun's UV radiation is most powerful between 10 a.m. and 4 p.m. To the extent possible, limit exposure to the direct sun during these hours. A hat with a generous brim can prevent nearly 50% of UV rays from reaching your eyes.
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What part of the year is the coldest in Walahanduwa?
How hot is it in Walahanduwa in September?
What are the most humid months in Walahanduwa?
What is the average humidity in September in Walahanduwa?
How much does it rain in Walahanduwa in September?
How many hours of daylight does Walahanduwa have in September?
What time are sunrise and sunset in September in Walahanduwa?
How long on average sun shines in September in Walahanduwa?
What are the months with the lowest UV index in Walahanduwa?
How high is the UV index in September in Walahanduwa?
Average temperature in September
Walahanduwa, 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
Walahanduwa, 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
Walahanduwa, 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
Walahanduwa, 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
Walahanduwa, 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
Walahanduwa, 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
Walahanduwa, Sri Lanka
- Average daylight in September: 12h and 1min
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 3min
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
Walahanduwa, 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
Walahanduwa, 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
Walahanduwa, 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
Walahanduwa, 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).
