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
The arrival of September corresponds with a minor reduction in the average high-temperature, down from August's comfortable 19.7°C (67.5°F) to a moderate 15.3°C (59.5°F). During September, the nighttime temperature averages of 10.2°C (50.4°F).Humidity
In September, the average relative humidity in Lieto is 79%.Rainfall
In Lieto, Finland, in September, during 13.6 rainfall days, 36mm (1.42") of precipitation is typically accumulated. Throughout the year, in Lieto, Finland, there are 133.7 rainfall days, and 390mm (15.35") of precipitation is accumulated.Snowfall
June through September are months without snowfall in Lieto.Daylight
In Lieto, Finland, the average length of the day in September is 12h and 53min.On the first day of September, sunrise is at 06:25 and sunset at 20:34. On the last day of the month, sunrise is at 07:34 and sunset at 19:05 EEST.
Sunshine
In Lieto, the average sunshine in September is 7.7h.UV index
In September, the average daily maximum UV index is 3. A UV Index value of 3 to 5 symbolizes a medium vulnerability from unprotected exposure to Sun's UV rays for the average person.Note: In September, a regular UV index of 3 translates into these guidelines:
Prioritize safety - Recommendations to avert sunburn are shared. Being in direct Sun during midday can be harmful due to intense solar radiation; take precautions. It's wise to wear UVA and UVB-blocking sunglasses when the sun shines brightly.
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the average September temperature?
What is the average humidity in September?
How much does it rain in September?
When it does not snow?
Does it snow in September?
How many hours of daylight does Lieto have in September?
When are sunrise and sunset in September in Lieto?
How long on average sun shines in September?
What is the UV index intensity in September?
Average temperature in September
Lieto, Finland
- Average high temperature in September: 15.3°C
The warmest month (with the highest average high temperature) is July (20.4°C).
The month with the lowest average high temperature is January (-1.9°C).
- Average low temperature in September: 10.2°C
The months with the highest average low temperature are July and August (13.8°C).
The coldest month (with the lowest average low temperature) is February (-5.6°C).
Average pressure in September
Lieto, Finland
- Average pressure in September: 1013.2mbar
The month with the highest atmospheric pressure is May (1014.9mbar).
The month with the lowest atmospheric pressure is December (1007.6mbar).
Average wind speed in September
Lieto, Finland
- Average wind speed in September: 15.8km/h
The windiest month (with the highest average wind speed) is December (20.4km/h).
The calmest month (with the lowest average wind speed) is July (13.9km/h).
Average humidity in September
Lieto, Finland
- Average humidity in September: 79%
The month with the highest relative humidity is February (91%).
The month with the lowest relative humidity is May (71%).
Average rainfall in September
Lieto, Finland
- Average rainfall in September: 36mm
The wettest month (with the highest rainfall) is July (49mm).
The driest month (with the least rainfall) is April (19mm).
Average rainfall days in September
Lieto, Finland
- Average rainfall days in September: 13.6 days
The month with the highest number of rainy days is July (15.1 days).
The month with the least rainy days is February (5.2 days).
Average snowfall in September
Lieto, Finland
- Average snowfall in September: 0mm
The month with the highest snowfall is January (103mm).
The months with the least snowfall are June, July, August and September (0mm).
Average snowfall days in September
Lieto, Finland
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (13.7 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Lieto, Finland
- Average daylight in September: 12h and 5min
The month with the longest days is June (Average daylight: 18h and 54min).
The month with the shortest days is December (Average daylight: 5h and 54min).
- Average sunshine in September: 7h and 4min
The month with the most sunshine is July (Average sunshine: 11h and 30min).
The month with the least sunshine is December (Average sunshine: 2h and 0min).
Average sunshine days in September
Lieto, Finland
- Average sunshine days in September: 13.2 days
The month with the most sunshine days is May (17.2 days).
The month with the least sunshine days is December (9.6 days).
Average UV index in September
Lieto, Finland
- Average UV index in September: 3
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, March, November and December (UV index 1).
Average cloud cover in September
Lieto, Finland
- Average cloud cover in September: 44
The month with the most cloud cover is December (Cloud cover 71).
The months with the least cloud cover are July and August (Cloud cover 36).
Average visibility in September
Lieto, Finland
- Average visibility in September: 10km
The months with the highest visibility are May, June, July, August and September (10km).
The months with the lowest visibility are February and March (8km).
