September weather forecastRennes, France
September
Weather in September
September marks the arrival of autumn in Rennes, France, with noticeable changes in weather patterns and temperatures. The mercury column displays a drop with maximum temperatures hovering around 20.8°C (69.4°F) on average. The decrease in precipitation to 12mm (0.47"), the lowest throughout the year, emphasizes the shift from summer to autumn. September brings out the mild and calm features of autumn, including a mellow sunshine, warm days, and less rainfall compared to the summertime.Temperature
September in Rennes begins with an average high-temperature of a pleasant 20.8°C (69.4°F), reflecting close similarity to the preceding month. Rennes experiences an average low-temperature of 10.8°C (51.4°F) in the month of September.Humidity
July through September, with an average relative humidity of 78%, are the least humid months in Rennes.Rainfall
September is the month with the least rainfall. Rain falls for 8.4 days and accumulates 12mm (0.47") of precipitation.Snowfall
In Rennes, snow does not fall in May through October.Daylight
In Rennes, France, the average length of the day in September is 12h and 34min.On the first day of September in Rennes, sunrise is at 07:25 and sunset at 20:47. On the last day of the month, sunrise is at 08:05 and sunset at 19:47 CEST.
Sunshine
The average sunshine in September is 7.5h.UV index
In Rennes, the average daily maximum UV index in September is 4. A UV Index value of 3 to 5 symbolizes a medium vulnerability from unsafe exposure to UV radiation for average individuals.Note: A maximum high daily UV index of 4 during September translates into the following directions:
Act with care - The need to guard against sun damage is communicated. For health reasons, it's advisable to reduce direct sun exposure during peak hours around midday. Safeguard your eyes, ears, and face from sun rays with the aid of a wide-brim hat.
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Rennes, France
- Average high temperature in September: 20.8°C
The warmest month (with the highest average high temperature) is August (23.1°C).
The month with the lowest average high temperature is January (8.4°C).
- Average low temperature in September: 10.8°C
The month with the highest average low temperature is July (12.8°C).
The coldest month (with the lowest average low temperature) is February (2.3°C).
Average pressure in September
Rennes, France
- Average pressure in September: 1018.3mbar
The month with the highest atmospheric pressure is December (1018.4mbar).
The month with the lowest atmospheric pressure is November (1012.9mbar).
Average wind speed in September
Rennes, France
- Average wind speed in September: 12.1km/h
The windiest month (with the highest average wind speed) is February (17.6km/h).
The calmest month (with the lowest average wind speed) is August (11.7km/h).
Average humidity in September
Rennes, France
- Average humidity in September: 78%
The month with the highest relative humidity is December (88%).
The months with the lowest relative humidity are July, August and September (78%).
Average rainfall in September
Rennes, France
- Average rainfall in September: 12mm
The wettest month (with the highest rainfall) is June (39mm).
The driest month (with the least rainfall) is September (12mm).
Average rainfall days in September
Rennes, France
- Average rainfall days in September: 8.4 days
The month with the highest number of rainy days is May (15.3 days).
The month with the least rainy days is September (8.4 days).
Average snowfall in September
Rennes, France
- Average snowfall in September: 0mm
The months with the highest snowfall are February, March, April and December (2mm).
The months with the least snowfall are May, June, July, August, September and October (0mm).
Average snowfall days in September
Rennes, France
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (0.8 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).
Average daylight in September /
Average sunshine in September
Rennes, France
- Average daylight in September: 12h and 36min
The month with the longest days is June (Average daylight: 16h and 0min).
The month with the shortest days is December (Average daylight: 8h and 24min).
- Average sunshine in September: 7h and 30min
The month with the most sunshine is July (Average sunshine: 9h and 42min).
The month with the least sunshine is January (Average sunshine: 4h and 12min).
Average sunshine days in September
Rennes, France
- Average sunshine days in September: 18.5 days
The month with the most sunshine days is September (18.5 days).
The month with the least sunshine days is May (12.1 days).
Average UV index in September
Rennes, France
- Average UV index in September: 4
The months with the highest UV index are June, July and August (UV index 5).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in September
Rennes, France
- Average cloud cover in September: 41
The month with the most cloud cover is January (Cloud cover 59).
The month with the least cloud cover is September (Cloud cover 41).
Average visibility in September
Rennes, France
- Average visibility in September: 8km
The months with the highest visibility are January, February, March, April, June, July, October, November and December (9km).
The months with the lowest visibility are May, August and September (8km).
