September weather forecastJonku, Finland
September
Weather in September
September, the first month of the autumn in Jonku, is also a fresh month, with temperature in the range of an average high of 12.4°C (54.3°F) and an average low of 5.5°C (41.9°F).Temperature
Stepping into September, Jonku observes a temperature decline, with the average high falling from August's refreshing 17.9°C (64.2°F) to a fresh 12.4°C (54.3°F). During September, Jonku experiences a consistent low-temperature average of 5.5°C (41.9°F).Humidity
In Jonku, Finland, the average relative humidity in September is 86%.Rainfall
In Jonku, in September, it is raining for 15.5 days, with typically 45mm (1.77") of accumulated precipitation. In Jonku, during the entire year, the rain falls for 134 days and collects up to 527mm (20.75") of precipitation.Snowfall
January through June, September through December are months with snowfall. September is the first month it typically snows. Throughout September, in the average 0.7 snowfall days, it receives 8mm (0.31") of snow. Throughout the year, there are 133.6 snowfall days, and 1512mm (59.53") of snow is accumulated.Daylight
The average length of the day in September is 13h and 5min.On the first day of September, sunrise is at 05:50 and sunset at 20:30. On the last day of the month, sunrise is at 07:19 and sunset at 18:42 EEST.
Sunshine
The average sunshine in September is 5.7h.UV index
In September, the average daily maximum UV index is 2. A UV Index value of 2, and less, symbolizes a low health risk from unsafe exposure to UV radiation for the ordinary person.Note: A daily high UV index of 2 in September leads to these guidelines:
While most people are not greatly affected by extended sun exposure, those with fair skin, babies, and children must always have protection. To guard against the harmful effects of the Sun, minimize exposure during midday. To best shield against UV radiation, choose sun-safe garments and dependable sunglasses. Mind you! Snow reflection can increase the intensity of the Sun's UV radiation nearly twofold.
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Jonku, Finland
- Average high temperature in September: 12.4°C
The warmest month (with the highest average high temperature) is July (20.7°C).
The month with the lowest average high temperature is January (-7.7°C).
- Average low temperature in September: 5.5°C
The month with the highest average low temperature is July (11°C).
The coldest month (with the lowest average low temperature) is January (-12.7°C).
Average pressure in September
Jonku, Finland
- Average pressure in September: 1011.2mbar
The month with the highest atmospheric pressure is May (1014.1mbar).
The month with the lowest atmospheric pressure is December (1005.7mbar).
Average wind speed in September
Jonku, Finland
- Average wind speed in September: 10.9km/h
The windiest month (with the highest average wind speed) is February (11.7km/h).
The calmest month (with the lowest average wind speed) is July (9.5km/h).
Average humidity in September
Jonku, Finland
- Average humidity in September: 86%
The months with the highest relative humidity are January, February and December (96%).
The month with the lowest relative humidity is June (69%).
Average rainfall in September
Jonku, Finland
- Average rainfall in September: 45mm
The wettest month (with the highest rainfall) is July (66mm).
The driest month (with the least rainfall) is April (29mm).
Average rainfall days in September
Jonku, Finland
- Average rainfall days in September: 15.5 days
The month with the highest number of rainy days is August (18.6 days).
The month with the least rainy days is February (2.6 days).
Average snowfall in September
Jonku, Finland
- Average snowfall in September: 8mm
The month with the highest snowfall is March (284mm).
The months with the least snowfall are July and August (0mm).
Average snowfall days in September
Jonku, Finland
- Average snowfall days in September: 0.7 days
The month with the highest number of snowfall days is December (23.5 days).
The months with the least snowfall days are July and August (0 days).
Average daylight in September /
Average sunshine in September
Jonku, Finland
- Average daylight in September: 13h and 6min
The month with the longest days is June (Average daylight: 22h and 0min).
The month with the shortest days is December (Average daylight: 3h and 42min).
- Average sunshine in September: 5h and 42min
The month with the most sunshine is July (Average sunshine: 11h and 30min).
The month with the least sunshine is December (Average sunshine: 0h and 42min).
Average sunshine days in September
Jonku, Finland
- Average sunshine days in September: 11.2 days
The month with the most sunshine days is October (12 days).
The month with the least sunshine days is April (6.8 days).
Average UV index in September
Jonku, Finland
- Average UV index in September: 2
The month with the highest UV index is July (UV index 5).
The months with the lowest UV index are January, February, March, October, November and December (UV index 1).
Average cloud cover in September
Jonku, Finland
- Average cloud cover in September: 64
The months with the most cloud cover are January and December (Cloud cover 81).
The month with the least cloud cover is July (Cloud cover 47).
Average visibility in September
Jonku, 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, February, March, April and December (5km).








