Helsinki · September
Run in the morning.
Cool month: average high 59°F, low 50°F. Humidity averages 81% — the limiting factor on most runs. Cool, runnable conditions throughout — morning still has the steadiest air and lightest wind.
Avg high / low
59° / 50°F
Humidity
81%
Rain days
14/mo
Wind
13 mph
What September feels like in Helsinki
Sunrise
06:49
Mid-month average
Sunset
19:40
Mid-month average
Time-of-day breakdown
Morning
Coolest, driest air of the day. The window before sunrise is the most reliable comfortable hour.
Midday
Mild but UV and traffic peak. Workable if you don't mind shifting your pace.
Evening
Warm and runnable. Crowded routes but the air's typically calm.
What to wear running in Helsinki in September
The kit for September in Helsinki: shorts and a short-sleeve are the standard kit, a water-resistant cap or jacket on standby.
September vs the surrounding months
vs August
-8° avg high
-3 rain days
Helsinki in August →
September
59°F avg high
14 rain days
Best: morning
vs October
+12° avg high
-3 rain days
Helsinki in October →
Frequently Asked Questions
What is the best time of day to run in Helsinki in September?+
Morning. Cool, runnable conditions throughout — morning still has the steadiest air and lightest wind.
What's the average temperature in Helsinki in September?+
Average high 59°F, average low 50°F.
How does September compare to surrounding months in Helsinki?+
Compared to August (avg high 68°F), September is cooler. Compared to October (avg high 48°F), September is warmer.
Does it rain often in Helsinki in September?+
Expect about 14 measurable rain days in September, on average.