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
With the commencement of September, Letten records a moderate temperature decline, with the average high easing from August's moderately hot 24.7°C (76.5°F) to an enjoyable 19.9°C (67.8°F). Letten throughout September, experiences an average nighttime temperature of 8.4°C (47.1°F).Humidity
The average relative humidity in September in Letten is 80%.Rainfall
In Letten, in September, it is raining for 10.2 days, with typically 24mm (0.94") of accumulated precipitation. Throughout the year, in Letten, there are 134.8 rainfall days, and 471mm (18.54") of precipitation is accumulated.Snowfall
June through September are months without snowfall in Letten.Daylight
The average length of the day in September in Letten, Switzerland, is 12h and 34min.On the first day of September, sunrise is at 06:45 and sunset at 20:06. On the last day of the month, sunrise is at 07:24 and sunset at 19:07 CEST.
Sunshine
In September, the average sunshine is 8.9h.UV index
The average daily maximum UV index in September is 4. A UV Index estimate of 3 to 5 represents a moderate threat to health from unprotected exposure to Sun's UV rays for average individuals.Note: In September, a regular UV index of 4 translates into these guidelines:
Act with care - Obligation to protect against skin and eye damage is highlighted. Stay safe from the Sun's strongest UV rays by limiting exposure during midday. 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
What are the temperatures in Letten in September?
What is the average humidity in September in Letten?
How many days does it rain in September in Letten?
When it does not snow in Letten?
Does it snow in Letten in September?
How many hours of daylight does Letten have in September?
When is the sunrise / sunset in September in Letten?
How many hours of sunshine does Letten have in September?
What is the UV index intensity in September in Letten?
Average temperature in September
Letten, Switzerland
- Average high temperature in September: 19.9°C
The warmest month (with the highest average high temperature) is July (24.8°C).
The month with the lowest average high temperature is January (3.2°C).
- Average low temperature in September: 8.4°C
The months with the highest average low temperature are July and August (12.2°C).
The coldest month (with the lowest average low temperature) is January (-3.2°C).
Average pressure in September
Letten, Switzerland
- Average pressure in September: 1018.6mbar
The month with the highest atmospheric pressure is December (1020.8mbar).
The month with the lowest atmospheric pressure is April (1015.7mbar).
Average wind speed in September
Letten, Switzerland
- Average wind speed in September: 6.3km/h
The windiest month (with the highest average wind speed) is March (8.7km/h).
The calmest month (with the lowest average wind speed) is August (6km/h).
Average humidity in September
Letten, Switzerland
- Average humidity in September: 80%
The month with the highest relative humidity is January (88%).
The month with the lowest relative humidity is July (75%).
Average rainfall in September
Letten, Switzerland
- Average rainfall in September: 24mm
The wettest month (with the highest rainfall) is July (61mm).
The driest month (with the least rainfall) is April (21mm).
Average rainfall days in September
Letten, Switzerland
- Average rainfall days in September: 10.2 days
The month with the highest number of rainy days is May (15.6 days).
The month with the least rainy days is February (8 days).
Average snowfall in September
Letten, Switzerland
- Average snowfall in September: 0mm
The month with the highest snowfall is December (85mm).
The months with the least snowfall are June, July, August and September (0mm).
Average snowfall days in September
Letten, Switzerland
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (8.3 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Letten, 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 months with the least sunshine are January, February and December (Average sunshine: 4h and 48min).
Average sunshine days in September
Letten, Switzerland
- Average sunshine days in September: 17.4 days
The month with the most sunshine days is October (19.5 days).
The month with the least sunshine days is May (13.6 days).
Average UV index in September
Letten, 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
Letten, Switzerland
- Average cloud cover in September: 36
The months with the most cloud cover are January and February (Cloud cover 54).
The month with the least cloud cover is August (Cloud cover 31).
Average visibility in September
Letten, Switzerland
- Average visibility in September: 8km
The months with the highest visibility are April, July and August (9km).
The month with the lowest visibility is January (7km).
