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
The transition into September notes an average high-temperature of a still warm 28.8°C (83.8°F), revealing a mild distinction from the 28.6°C (83.5°F) in August. In the month of September, Thanthirimulla experiences a minor discrepancy from peak daytime temperatures, settling at an average low-temperature of 25.2°C (77.4°F).Heat index
The heat index for September is appraised at a sweltering 35°C (95°F). Take extra precautions, as heat cramps and heat exhaustion are possible. Sustained activity may result in heatstroke.Heat index determinations are made taking into account the shade and light air movements. Heat index values might soar by up to 15 Fahrenheit (8 Celsius) degrees with exposure to direct sunshine.
Note: The heat index, also known as 'real feel' or 'apparent temperature', evaluates the perceived heat by adding the effect of moisture in the air. Elements such as metabolic variations, pregnancy, and physical exertion can shape one's weather perception. Direct exposure to the sun's rays can enhance the felt temperature, increasing the heat index by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are quite important for babies and toddlers. Children frequently do not understand the need for recuperation and hydration. Thirst, being a late manifestation of dehydration, underlines the need to hydrate frequently, especially when engaging in prolonged physical exercises.
To combat high temperatures, the human body perspires and relies on sweat evaporation for cooling. Higher relative humidity impedes evaporation, thus reducing heat dispersion from the body, culminating in a sensation of overheating. Heat-related disorders may develop if heat gain in the body overshadows its cooling capacity, leading to elevated temperatures.
Humidity
The average relative humidity in September is 82%.Rainfall
In Thanthirimulla, in September, it is raining for 26.3 days, with typically 201mm (7.91") of accumulated precipitation. Throughout the year, there are 273.8 rainfall days, and 2059mm (81.06") of precipitation is accumulated.Daylight
In September, the average length of the day is 12h and 10min.On the first day of September, sunrise is at 06:02 and sunset at 18:17. On the last day of the month, sunrise is at 05:58 and sunset at 18:02 +0530.
Sunshine
In Thanthirimulla, the average sunshine in September is 7.6h.UV index
The months with the highest UV index are January through April, July, September through December, with an average maximum UV index of 7. A UV Index value of 6 to 7 symbolizes a high health risk from exposure to the Sun's UV radiation for ordinary individuals.Note: An average maximum UV index of 7 in September leads to these recommendations:
Skirt overexposure. People with light complexions might get scorched in under 20 minutes. From 10 a.m. to 4 p.m., when UV radiation is at its strongest, limit direct exposure to the Sun and note that shade structures may not provide full sun protection. Equip yourself with UVA and UVB-filtering sunglasses on clear, sunny days.
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How hot is September?
What is the average humidity in September?
How many days does it rain in September?
What is the average length of the day in September?
What time are sunrise and sunset in September?
How many hours of sunshine does Thanthirimulla have in September?
What are the months with the highest UV index?
What is the UV index reading in September?
Average temperature in September
Thanthirimulla, Sri Lanka
- Average high temperature in September: 28.8°C
The warmest months (with the highest average high temperature) are March and April (31.3°C).
The month with the lowest average high temperature is August (28.6°C).
- Average low temperature in September: 25.2°C
The month with the highest average low temperature is May (26.3°C).
The coldest month (with the lowest average low temperature) is January (23.4°C).
Average pressure in September
Thanthirimulla, Sri Lanka
- Average pressure in September: 1009.9mbar
The month with the highest atmospheric pressure is January (1011.6mbar).
The month with the lowest atmospheric pressure is May (1008.7mbar).
Average wind speed in September
Thanthirimulla, Sri Lanka
- Average wind speed in September: 13.6km/h
The windiest month (with the highest average wind speed) is June (15.9km/h).
The calmest month (with the lowest average wind speed) is March (7.9km/h).
Average humidity in September
Thanthirimulla, Sri Lanka
- Average humidity in September: 82%
The months with the highest relative humidity are June, July and August (83%).
The months with the lowest relative humidity are January and February (75%).
Average rainfall in September
Thanthirimulla, Sri Lanka
- Average rainfall in September: 201mm
The wettest month (with the highest rainfall) is June (350mm).
The driest month (with the least rainfall) is January (25mm).
Average rainfall days in September
Thanthirimulla, Sri Lanka
- Average rainfall days in September: 26.3 days
The months with the highest number of rainy days are July and August (29.5 days).
The month with the least rainy days is January (8.9 days).
Average daylight in September /
Average sunshine in September
Thanthirimulla, 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 42min).
- Average sunshine in September: 7h and 4min
The month with the most sunshine is January (Average sunshine: 9h and 12min).
The month with the least sunshine is November (Average sunshine: 6h and 48min).
Average sunshine days in September
Thanthirimulla, Sri Lanka
- Average sunshine days in September: 1.4 days
The month with the most sunshine days is January (21 days).
The months with the least sunshine days are June and July (0.3 days).
Average UV index in September
Thanthirimulla, Sri Lanka
- Average UV index in September: 7
The months with the highest UV index are January, February, March, April, July, September, October, November and December (UV index 7).
The months with the lowest UV index are May, June and August (UV index 6).
Average cloud cover in September
Thanthirimulla, Sri Lanka
- Average cloud cover in September: 54
The month with the most cloud cover is June (Cloud cover 55).
The month with the least cloud cover is January (Cloud cover 24).
Average visibility in September
Thanthirimulla, Sri Lanka
- Average visibility in September: 9km
The months with the highest visibility are January, February, March, April, November and December (10km).
The months with the lowest visibility are May, June, July, August, September and October (9km).
