September weather forecastPetruma, Finland
September
Weather in September
The first month of the autumn, September, is still a mild month in Petruma, Finland, with an average temperature varying between 7.7°C (45.9°F) and 13.5°C (56.3°F).Temperature
The arrival of September indicates a decrease in the average high-temperature, moving from an enjoyable 19.3°C (66.7°F) in August to a moderate 13.5°C (56.3°F). Petruma encounters an average low-temperature of 7.7°C (45.9°F) during September nights.Humidity
The average relative humidity in September is 84%.Rainfall
In Petruma, in September, during 16.8 rainfall days, 49mm (1.93") of precipitation is typically accumulated. In Petruma, during the entire year, the rain falls for 127.8 days and collects up to 468mm (18.43") of precipitation.Snowfall
Months with snowfall are January through June, September through December. September is the first month it typically snows. Throughout September, in the average 0.6 snowfall days, it receives 5mm (0.2") of snow. In Petruma, during the entire year, snow falls for 120.8 days and aggregates up to 1095mm (43.11") of snow.Daylight
The average length of the day in September is 12h and 58min.On the first day of September, sunrise is at 05:54 and sunset at 20:15. On the last day of the month, sunrise is at 07:10 and sunset at 18:38 EEST.
Sunshine
In Petruma, the average sunshine in September is 6.3h.UV index
In Petruma, the average daily maximum UV index in September is 3. A UV Index of 3 to 5 symbolizes a moderate threat to health from exposure to the Sun's UV rays for average individuals.Note: During September, 3 as the daily maximum UV index converts into the following advice:
Take necessary precautions - Defending against sun damage is advocated. Exposing oneself to the midday Sun can be harmful due to the strong UV radiation; limit your time outside. Sunglasses that ward off UVA and UVB rays play a pivotal role in reducing solar eye damage. Be careful! The Sun's UV radiation can nearly be doubled by the reflective quality of snow.
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Petruma, Finland
- Average high temperature in September: 13.5°C
The warmest month (with the highest average high temperature) is July (21.2°C).
The month with the lowest average high temperature is January (-6.4°C).
- Average low temperature in September: 7.7°C
The month with the highest average low temperature is July (12.5°C).
The coldest month (with the lowest average low temperature) is January (-10.4°C).
Average pressure in September
Petruma, Finland
- Average pressure in September: 1012.8mbar
The month with the highest atmospheric pressure is May (1014.7mbar).
The month with the lowest atmospheric pressure is December (1008.6mbar).
Average wind speed in September
Petruma, Finland
- Average wind speed in September: 12.2km/h
The windiest months (with the highest average wind speed) are November and December (13.8km/h).
The calmest month (with the lowest average wind speed) is July (10.2km/h).
Average humidity in September
Petruma, Finland
- Average humidity in September: 84%
The month with the highest relative humidity is February (96%).
The months with the lowest relative humidity are May and June (68%).
Average rainfall in September
Petruma, Finland
- Average rainfall in September: 49mm
The wettest month (with the highest rainfall) is July (66mm).
The driest month (with the least rainfall) is April (26mm).
Average rainfall days in September
Petruma, Finland
- Average rainfall days in September: 16.8 days
The month with the highest number of rainy days is July (17.3 days).
The month with the least rainy days is February (2 days).
Average snowfall in September
Petruma, Finland
- Average snowfall in September: 5mm
The month with the highest snowfall is March (202mm).
The months with the least snowfall are July and August (0mm).
Average snowfall days in September
Petruma, Finland
- Average snowfall days in September: 0.6 days
The month with the highest number of snowfall days is December (22.3 days).
The months with the least snowfall days are July and August (0 days).
Average daylight in September /
Average sunshine in September
Petruma, Finland
- Average daylight in September: 13h and 0min
The month with the longest days is June (Average daylight: 19h and 48min).
The month with the shortest days is December (Average daylight: 5h and 12min).
- Average sunshine in September: 6h and 18min
The month with the most sunshine is June (Average sunshine: 12h and 0min).
The month with the least sunshine is December (Average sunshine: 0h and 36min).
Average sunshine days in September
Petruma, Finland
- Average sunshine days in September: 10.3 days
The month with the most sunshine days is May (15 days).
The month with the least sunshine days is February (7.7 days).
Average UV index in September
Petruma, 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
Petruma, Finland
- Average cloud cover in September: 59
The month with the most cloud cover is February (Cloud cover 84).
The month with the least cloud cover is July (Cloud cover 42).
Average visibility in September
Petruma, Finland
- Average visibility in September: 8km
The months with the highest visibility are May, June, July and August (9km).
The months with the lowest visibility are January and February (5km).





