Cool
Average highs are around 14°C, so pack for cooler days.
September verdict
Helsinki, Finland in September
Weather score21Poor
Poor for holiday weather
Average highs are around 14°C, so pack for cooler days. Sunshine averages 4.1h per day, so this is not one of the brighter months. Rainfall averages 73mm, which is relatively low for holiday planning.
September weather
Monthly averages
Temp
14°C
Rain
73mm
Sun
4.1h
Sea
15°C
Weather score
21
Poor
Seasonal climate calendar
TemperatureTemp
RainRain
SunSun
SwimSwim
Weather scoreWeather score
Trip feel
Drier
Rainfall averages 73mm, which is relatively low for holiday planning.
Limited sun
Sunshine averages 4.1h per day, so this is not one of the brighter months.
Cool sea
Sea temperatures average 15°C, so the water can feel cool.
Map
Weather map
Compare Helsinki, Finland with nearby places by weather score, rain, sun, temperature, and swim conditions.
Temperature
September14°C average high
September sits in the warmer part of the year, so midday sightseeing can feel heavier than in cooler months.
Warmest monthsJune to August
This stretch sets the upper range for average daytime heat.
Rain
September73mm average rain
September is one of Helsinki's wettest months, so rain is likely to be a major planning factor.
Driest monthsJanuary to June and December
This is the drier part of the year, when outdoor plans usually need less weather flexibility.
Sun
September4.1 hours average sun
September sits close to Helsinki's yearly sunshine average, so it is a middle-of-the-pack month for bright days.
Brightest monthsMay to July
This stretch has the strongest sunshine in the monthly averages.
Sea temperature
September15°C average sea
September sits in the warmer sea-temperature season, usually making swimming easier to enjoy.
Warmest seaJuly to September
Sea temperatures are usually near 17°C in this stretch, so swimming comfort is at its strongest.
Weather score
September21 weather score
September scores below Helsinki's yearly average, so the weather trade-offs are more noticeable.
Best weather monthsJune to August
These months have the strongest weather score in the monthly averages.
