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 snowfall in September
- Average snowfall 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
Weather in September
Temperature
The arrival of September signals a subtle shift in temperature, down from an agreeable 22.9°C (73.2°F) in August to a refreshing 18.3°C (64.9°F). Illiswil records an average temperature drop to a frosty 7.5°C (45.5°F) in September.Humidity
In September, the average relative humidity is 81%.Rainfall
The month with the least rainfall in Illiswil, Switzerland, is September, when the rain falls for 11.5 days and typically collects 23mm (0.91") of precipitation.Snowfall
In Illiswil, snow does not fall in June through September.Daylight
In Illiswil, the average length of the day in September is 12h and 34min.On the first day of September, sunrise is at 06:50 and sunset at 20:10. On the last day of the month, sunrise is at 07:28 and sunset at 19:12 CEST.
Sunshine
The average sunshine in September is 8.7h.UV index
In September, the average daily maximum UV index is 4. A UV Index estimate of 3 to 5 represents a medium health hazard from unprotected exposure to Sun's UV rays for the average person.Note: A maximum high UV index of 4 in September translates into the following recommendations:
Put precautions into practice - Ensuring skin and eye safety is a necessity. Being exposed to the midday Sun can have harmful effects due to strong UV radiation; always take precautions. Opt for tightly woven and loose clothing to enhance protection from the Sun.
Frequently asked questions
What is the temperature in September in Illiswil?
What is the average humidity in September in Illiswil?
What is the driest month in Illiswil?
How many days does it rain in September in Illiswil?
When it does not snow in Illiswil?
Does it snow in Illiswil in September?
What is the average length of the day in September in Illiswil?
When is the sunrise / sunset in September in Illiswil?
How long on average sun shines in September in Illiswil?
What is the UV index intensity in September in Illiswil?
Average temperature in September
Illiswil, Switzerland
- Average high temperature in September: 18.3°C
The warmest month (with the highest average high temperature) is July (23.1°C).
The month with the lowest average high temperature is January (2.9°C).
- Average low temperature in September: 7.5°C
The month with the highest average low temperature is July (11.2°C).
The coldest month (with the lowest average low temperature) is February (-4.2°C).
Average pressure in September
Illiswil, Switzerland
- Average pressure in September: 1018.6mbar
The month with the highest atmospheric pressure is December (1021mbar).
The month with the lowest atmospheric pressure is April (1015.5mbar).
Average wind speed in September
Illiswil, Switzerland
- Average wind speed in September: 6.7km/h
The windiest month (with the highest average wind speed) is March (9km/h).
The calmest month (with the lowest average wind speed) is August (6.2km/h).
Average humidity in September
Illiswil, Switzerland
- Average humidity in September: 81%
The months with the highest relative humidity are January and February (85%).
The months with the lowest relative humidity are April, July and August (77%).
Average rainfall in September
Illiswil, Switzerland
- Average rainfall in September: 23mm
The wettest month (with the highest rainfall) is June (54mm).
The driest month (with the least rainfall) is September (23mm).
Average rainfall days in September
Illiswil, Switzerland
- Average rainfall days in September: 11.5 days
The month with the highest number of rainy days is May (18.3 days).
The month with the least rainy days is February (8.1 days).
Average snowfall in September
Illiswil, Switzerland
- Average snowfall in September: 0mm
The month with the highest snowfall is February (104mm).
The months with the least snowfall are June, July, August and September (0mm).
Average snowfall days in September
Illiswil, Switzerland
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (9.8 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Illiswil, Switzerland
- Average daylight in September: 12h and 4min
The month with the longest days is June (Average daylight: 15h and 48min).
The month with the shortest days is December (Average daylight: 8h and 36min).
- Average sunshine in September: 8h and 4min
The month with the most sunshine is August (Average sunshine: 10h and 18min).
The months with the least sunshine are January and December (Average sunshine: 5h and 18min).
Average sunshine days in September
Illiswil, Switzerland
- Average sunshine days in September: 14.2 days
The month with the most sunshine days is October (19.5 days).
The months with the least sunshine days are May and June (9.3 days).
Average UV index in September
Illiswil, Switzerland
- Average UV index in September: 4
The months with the highest UV index are June and July (UV index 5).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in September
Illiswil, Switzerland
- Average cloud cover in September: 35
The month with the most cloud cover is February (Cloud cover 47).
The month with the least cloud cover is August (Cloud cover 32).
Average visibility in September
Illiswil, Switzerland
- Average visibility in September: 8km
The months with the highest visibility are March, April and December (9km).
The months with the lowest visibility are January, February, May, June, July, August, September, October and November (8km).
Illiswil, Switzerland
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