September weather forecastSievi, Finland
September
Weather in September
September, the first month of the autumn in Sievi, is still a refreshing month, with an average temperature ranging between min 6.4°C (43.5°F) and max 13.3°C (55.9°F).Temperature
The transition into September is accompanied by a temperature decrease, with the average high-temperature shifting from an enjoyable 19.1°C (66.4°F) in August to a mild 13.3°C (55.9°F). An average low-temperature of 6.4°C (43.5°F) is noted during the month of September.Humidity
The average relative humidity in September is 84%.Rainfall
In Sievi, during September, the rain falls for 12.1 days and regularly aggregates up to 28mm (1.1") of precipitation. Throughout the year, there are 118.8 rainfall days, and 391mm (15.39") of precipitation is accumulated.Snowfall
June through September are months without snowfall.Daylight
The average length of the day in September is 13h and 1min.On the first day of the month, sunrise is at 06:06 and sunset at 20:36. On the last day of September, sunrise is at 07:29 and sunset at 18:54 EEST.
Sunshine
In Sievi, the average sunshine in September is 6.2h.UV index
In September, the average daily maximum UV index is 3. A UV Index estimate of 3 to 5 represents a medium vulnerability from unsafe exposure to UV radiation for average individuals.Note: The maximum daily UV index of 3 in September interprets into the following recommendations:
Proceed with care. Light skin individuals may be exposed to burns in fewer than 30 minutes. Avoiding direct sun during mid-day hours can prevent harmful UV radiation exposure. Sunglasses that ward off UVA and UVB rays play a pivotal role in reducing solar eye damage. Be alert! Nearly double the UV rays from the Sun can be reflected by snow.
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Sievi, Finland
- Average high temperature in September: 13.3°C
The warmest month (with the highest average high temperature) is July (21°C).
The month with the lowest average high temperature is January (-5.8°C).
- Average low temperature in September: 6.4°C
The month with the highest average low temperature is July (11.4°C).
The coldest month (with the lowest average low temperature) is January (-10°C).
Average pressure in September
Sievi, Finland
- Average pressure in September: 1011.8mbar
The month with the highest atmospheric pressure is May (1014.2mbar).
The month with the lowest atmospheric pressure is December (1006mbar).
Average wind speed in September
Sievi, Finland
- Average wind speed in September: 10.2km/h
The windiest month (with the highest average wind speed) is December (11.5km/h).
The calmest month (with the lowest average wind speed) is July (8.9km/h).
Average humidity in September
Sievi, Finland
- Average humidity in September: 84%
The month with the highest relative humidity is January (96%).
The month with the lowest relative humidity is June (67%).
Average rainfall in September
Sievi, Finland
- Average rainfall in September: 28mm
The wettest month (with the highest rainfall) is July (49mm).
The driest month (with the least rainfall) is April (23mm).
Average rainfall days in September
Sievi, Finland
- Average rainfall days in September: 12.1 days
The month with the highest number of rainy days is July (15.5 days).
The month with the least rainy days is February (3.3 days).
Average snowfall in September
Sievi, Finland
- Average snowfall in September: 0mm
The month with the highest snowfall is December (200mm).
The months with the least snowfall are June, July, August and September (0mm).
Average snowfall days in September
Sievi, Finland
- Average snowfall days in September: 0.1 days
The month with the highest number of snowfall days is January (21.6 days).
The months with the least snowfall days are June, July and August (0 days).
Average daylight in September /
Average sunshine in September
Sievi, Finland
- Average daylight in September: 13h and 0min
The month with the longest days is June (Average daylight: 20h and 42min).
The month with the shortest days is December (Average daylight: 4h and 30min).
- Average sunshine in September: 6h and 12min
The month with the most sunshine is June (Average sunshine: 11h and 36min).
The month with the least sunshine is December (Average sunshine: 0h and 54min).
Average sunshine days in September
Sievi, Finland
- Average sunshine days in September: 15.5 days
The month with the most sunshine days is May (17.2 days).
The month with the least sunshine days is December (8.5 days).
Average UV index in September
Sievi, Finland
- Average UV index in September: 3
The month with the highest UV index is July (UV index 5).
The months with the lowest UV index are January, February, March, November and December (UV index 1).
Average cloud cover in September
Sievi, Finland
- Average cloud cover in September: 61
The month with the most cloud cover is January (Cloud cover 80).
The month with the least cloud cover is June (Cloud cover 47).
Average visibility in September
Sievi, Finland
- Average visibility in September: 7km
The months with the highest visibility are May, June and July (9km).
The months with the lowest visibility are January and February (5km).





