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
Mandandawela notes an average high-temperature of a still tropical 31.2°C (88.2°F) in September, displaying minor variation from August. An average nighttime temperature of 22.3°C (72.1°F) is witnessed in Mandandawela throughout September.Heat index
September's average heat index is evaluated at a very hot 39°C (102.2°F). Implement more safety precautions, heat cramps and heat exhaustion may happen. Persistent activity could induce heatstroke.Be aware that heat index ratings are designed for shaded locations and minor breezes. Exposure to unobstructed sunshine could lead to an increase in the heat index by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'feels like' or 'felt air temperature', is achieved by amalgamating air temperature with the relative humidity readings. Factors such as metabolic variations, being pregnant, and physical activity can impact an individual's weather perception. One should be aware that direct sunshine can amplify the perceived temperature, raising the heat index by as much as 15 Fahrenheit (8 Celsius) degrees. Heat index values remain especially vital for babies and toddlers. Young children are generally more endangered than adults, as they usually less sweat. And also, due to larger skin surface relative to their small bodies and higher heat production as a result of their activity.
The natural cooling mechanism in humans involves perspiration, where the evaporation of sweat balances out excessive warmth. In circumstances of high air temperature and humidity (high heat index), the body's perspiration is restricted, heightening the feeling of warmth. As the body gains more heat than it can dissipate, there's a risk of increasing temperatures and resultant overheating.
Humidity
The months with the lowest humidity are March and September, with an average relative humidity of 72%.Rainfall
In September, the rain falls for 15.2 days. Throughout September, 72mm (2.83") of precipitation is accumulated. In Mandandawela, during the entire year, the rain falls for 217.7 days and collects up to 1165mm (45.87") of precipitation.Daylight
The average length of the day in September is 12h and 10min.On the first day of September, sunrise is at 05:59 and sunset at 18:15. On the last day of the month, sunrise is at 05:55 and sunset at 17:59 +0530.
Sunshine
The average sunshine in September is 10.5h.UV index
March through September, with an average maximum UV index of 7, are months with the highest UV index. A UV Index reading of 6 to 7 represents a high health vulnerability from unprotected exposure to Sun's UV rays for the ordinary person.Note: The daily high UV index of 7 in September translates into this advice:
Beware of overexposure. Fair-skinned individuals risk burning in less than 20 minutes. The Sun's UV radiation is at its strongest between the hours of 10 a.m. and 4 p.m. Minimize direct exposure to the sun during this period. Sunglasses providing both UVA and UVB protection are non-negotiable on sunlit days.
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How hot is it in September?
What are the least humid months?
What is the average humidity in September in Mandandawela?
How many days does it rain in September?
What is the average length of the day in September?
When is the sunrise / sunset in September?
How many hours of sunshine does Mandandawela have in September?
What are the months with the highest UV index?
What is the UV index intensity in September?
Average temperature in September
Mandandawela, Sri Lanka
- Average high temperature in September: 31.2°C
The warmest month (with the highest average high temperature) is April (32.9°C).
The month with the lowest average high temperature is December (28.6°C).
- Average low temperature in September: 22.3°C
The month with the highest average low temperature is May (23°C).
The coldest month (with the lowest average low temperature) is February (18.9°C).
Average pressure in September
Mandandawela, Sri Lanka
- Average pressure in September: 1009.2mbar
The month with the highest atmospheric pressure is January (1011.9mbar).
The month with the lowest atmospheric pressure is June (1007.9mbar).
Average wind speed in September
Mandandawela, Sri Lanka
- Average wind speed in September: 13.2km/h
The windiest month (with the highest average wind speed) is June (16.5km/h).
The calmest month (with the lowest average wind speed) is April (5.6km/h).
Average humidity in September
Mandandawela, Sri Lanka
- Average humidity in September: 72%
The month with the highest relative humidity is December (83%).
The months with the lowest relative humidity are March and September (72%).
Average rainfall in September
Mandandawela, Sri Lanka
- Average rainfall in September: 72mm
The wettest month (with the highest rainfall) is October (267mm).
The driest month (with the least rainfall) is June (29mm).
Average rainfall days in September
Mandandawela, Sri Lanka
- Average rainfall days in September: 15.2 days
The month with the highest number of rainy days is April (24.7 days).
The month with the least rainy days is February (11.8 days).
Average daylight in September /
Average sunshine in September
Mandandawela, Sri Lanka
- Average daylight in September: 12h and 1min
The month with the longest days is June (Average daylight: 12h and 36min).
The month with the shortest days is December (Average daylight: 11h and 42min).
- Average sunshine in September: 10h and 3min
The month with the most sunshine is June (Average sunshine: 11h and 0min).
The month with the least sunshine is December (Average sunshine: 5h and 42min).
Average sunshine days in September
Mandandawela, Sri Lanka
- Average sunshine days in September: 10.5 days
The month with the most sunshine days is January (14.8 days).
The month with the least sunshine days is April (4 days).
Average UV index in September
Mandandawela, Sri Lanka
- Average UV index in September: 7
The months with the highest UV index are March, April, May, June, July, August and September (UV index 7).
The months with the lowest UV index are January, February, October, November and December (UV index 6).
Average cloud cover in September
Mandandawela, Sri Lanka
- Average cloud cover in September: 31
The months with the most cloud cover are November and December (Cloud cover 46).
The month with the least cloud cover is March (Cloud cover 24).
Average visibility in September
Mandandawela, Sri Lanka
- Average visibility in September: 10km
The months with the highest visibility are June, July, August and September (10km).
The months with the lowest visibility are January, November and December (8km).
