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
September
Weather in September
Temperature
The onset of September in Aarau aligns with a soft reduction in the average high-temperature, gently falling from a warm 23.3°C (73.9°F) in August to an enjoyable 18.8°C (65.8°F). Aarau's nighttime temperature in September drops to an average of 8.2°C (46.8°F).Humidity
The average relative humidity in September is 81%.Rainfall
September is the month with the least rainfall in Aarau. Rain falls for 14.5 days and accumulates 45mm (1.77") of precipitation.Snowfall
In Aarau, snow does not fall in June through September.Daylight
In Aarau, the average length of the day in September is 12h and 34min.On the first day of the month, sunrise is at 06:47 and sunset at 20:07. On the last day of September, sunrise is at 07:26 and sunset at 19:09 CEST.
Sunshine
The average sunshine in September is 8.9h.UV index
In Aarau, the average daily maximum UV index in September is 4. A UV Index value of 3 to 5 symbolizes a moderate threat to health from exposure to the Sun's UV rays for ordinary individuals.Note: The UV index of 4 during September translates into the following guidance:
Take precautions. Light skin individuals may get burned in less than 30 minutes. The Sun's UV radiation is especially harmful around midday, so reduce exposure and stay safe. To mitigate harm from sun exposure, pick sunglasses offering UVA and UVB defense.
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What are the temperatures in September?
What is the average humidity in September?
What is the driest month?
How much does it rain in September?
When it does not snow?
Does it snow in September?
How many hours of daylight does Aarau have in September?
When are sunrise and sunset in September?
How many hours of sunshine does Aarau have in September?
What is the UV index reading in September?
Average temperature in September
Aarau, Switzerland
- Average high temperature in September: 18.8°C
The warmest months (with the highest average high temperature) are July and August (23.3°C).
The month with the lowest average high temperature is January (2.9°C).
- Average low temperature in September: 8.2°C
The months with the highest average low temperature are July and August (11.8°C).
The coldest month (with the lowest average low temperature) is February (-3.4°C).
Average pressure in September
Aarau, Switzerland
- Average pressure in September: 1018.6mbar
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
Aarau, Switzerland
- Average wind speed in September: 6.4km/h
The windiest month (with the highest average wind speed) is March (8.8km/h).
The calmest month (with the lowest average wind speed) is August (5.9km/h).
Average humidity in September
Aarau, Switzerland
- Average humidity in September: 81%
The month with the highest relative humidity is January (88%).
The months with the lowest relative humidity are April and July (78%).
Average rainfall in September
Aarau, Switzerland
- Average rainfall in September: 45mm
The wettest month (with the highest rainfall) is May (106mm).
The driest month (with the least rainfall) is September (45mm).
Average rainfall days in September
Aarau, Switzerland
- Average rainfall days in September: 14.5 days
The month with the highest number of rainy days is May (22.4 days).
The month with the least rainy days is February (10.6 days).
Average snowfall in September
Aarau, Switzerland
- Average snowfall in September: 0mm
The month with the highest snowfall is February (153mm).
The months with the least snowfall are June, July, August and September (0mm).
Average snowfall days in September
Aarau, Switzerland
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (9.7 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Aarau, Switzerland
- Average daylight in September: 12h and 4min
The month with the longest days is June (Average daylight: 15h and 54min).
The month with the shortest days is December (Average daylight: 8h and 30min).
- Average sunshine in September: 8h and 5min
The month with the most sunshine is August (Average sunshine: 10h and 24min).
The month with the least sunshine is December (Average sunshine: 5h and 0min).
Average sunshine days in September
Aarau, Switzerland
- Average sunshine days in September: 12.2 days
The month with the most sunshine days is October (15 days).
The month with the least sunshine days is May (6.6 days).
Average UV index in September
Aarau, 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, October, November and December (UV index 2).
Average cloud cover in September
Aarau, Switzerland
- Average cloud cover in September: 34
The month with the most cloud cover is January (Cloud cover 49).
The month with the least cloud cover is August (Cloud cover 32).
Average visibility in September
Aarau, Switzerland
- Average visibility in September: 8km
The months with the highest visibility are March, April, July and August (9km).
The months with the lowest visibility are January, February, May, June, September, October, November and December (8km).
