September weather forecastArth, Switzerland
September
Weather in September
September, the first month of the autumn in Arth, is still a comfortable month, with an average temperature fluctuating between 7.5°C (45.5°F) and 17.5°C (63.5°F).Temperature
September brings a slight decrease in temperature, down from a pleasant 22.1°C (71.8°F) in August to a refreshing 17.5°C (63.5°F). During September nights, Arth witnesses a consistent average temperature of 7.5°C (45.5°F).Humidity
In September, the average relative humidity is 80%.Rainfall
The month with the least rainfall is September, when the rain falls for 14.3 days and typically collects 52mm (2.05") of precipitation.Snowfall
June through September are months without snowfall in Arth.Daylight
In Arth, the average length of the day in September is 12h and 34min.On the first day of September in Arth, sunrise is at 06:45 and sunset at 20:05. On the last day of the month, sunrise is at 07:23 and sunset at 19:07 CEST.
Sunshine
The average sunshine in September in Arth is 8.9h.UV index
In September, the average daily maximum UV index is 4. A UV Index value of 3 to 5 symbolizes a moderate threat to health from exposure to the Sun's UV radiation for the ordinary person.Note: An average maximum UV index of 4 in September leads to these recommendations:
Ensure safety - Sun damage prevention is strongly urged. The solar radiation around mid-day is intense; avoid the Sun and stay safe. A wide-brimmed hat provides unparalleled sun protection for sensitive areas like the eyes, ears, and neck.
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Arth, Switzerland
- Average high temperature in September: 17.5°C
The warmest month (with the highest average high temperature) is August (22.1°C).
The month with the lowest average high temperature is January (2.2°C).
- Average low temperature in September: 7.5°C
The month with the highest average low temperature is August (10.9°C).
The coldest month (with the lowest average low temperature) is February (-4.9°C).
Average pressure in September
Arth, Switzerland
- Average pressure in September: 1018.5mbar
The month with the highest atmospheric pressure is December (1020.9mbar).
The month with the lowest atmospheric pressure is April (1015.6mbar).
Average wind speed in September
Arth, Switzerland
- Average wind speed in September: 6.3km/h
The windiest month (with the highest average wind speed) is December (8.3km/h).
The calmest month (with the lowest average wind speed) is August (6.2km/h).
Average humidity in September
Arth, Switzerland
- Average humidity in September: 80%
The months with the highest relative humidity are January and February (86%).
The months with the lowest relative humidity are July and August (77%).
Average rainfall in September
Arth, Switzerland
- Average rainfall in September: 52mm
The wettest month (with the highest rainfall) is July (121mm).
The driest month (with the least rainfall) is September (52mm).
Average rainfall days in September
Arth, Switzerland
- Average rainfall days in September: 14.3 days
The month with the highest number of rainy days is May (21.5 days).
The month with the least rainy days is October (11.2 days).
Average snowfall in September
Arth, Switzerland
- Average snowfall in September: 0mm
The month with the highest snowfall is February (169mm).
The months with the least snowfall are June, July, August and September (0mm).
Average snowfall days in September
Arth, Switzerland
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (9.2 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Arth, Switzerland
- Average daylight in September: 12h and 36min
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 54min
The month with the most sunshine is July (Average sunshine: 10h and 18min).
The month with the least sunshine is December (Average sunshine: 5h and 24min).
Average sunshine days in September
Arth, Switzerland
- Average sunshine days in September: 13 days
The month with the most sunshine days is October (18.4 days).
The month with the least sunshine days is June (7.3 days).
Average UV index in September
Arth, 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, March, November and December (UV index 2).
Average cloud cover in September
Arth, Switzerland
- Average cloud cover in September: 34
The month with the most cloud cover is February (Cloud cover 44).
The month with the least cloud cover is August (Cloud cover 33).
Average visibility in September
Arth, Switzerland
- Average visibility in September: 8km
The months with the highest visibility are February, March, April, May, June, July, August, September, October, November and December (8km).
The month with the lowest visibility is January (7km).





