Seinäjoki Weather in September
Seinäjoki in September sees moderate daytime temperatures of 15°C (59°F) and nighttime lows of 6°C (43°F). Moderate rainfall is typical, with around 60 mm (2.4 in) for the month.
Rainfall in Seinäjoki in September
Rain is expected on roughly 17 days, totalling around 60 mm (2.4 in) for the month. Expect plenty of grey, overcast days rather than intense storms. The rain rarely amounts to much on any given day.
Temperature in Seinäjoki in September
September in Seinäjoki brings typical temperatures with highs around 15°C (59°F) and lows of 6°C (43°F). Temperatures can feel cooler in the morning and evening, so layering is often the best approach. Nights fall to 6°C (43°F), which is cold enough to feel it indoors too. A good thick duvet makes all the difference for a comfortable night's sleep.
Sunshine in Seinäjoki in September
You can expect a moderate amount of sunlight, with approximately 135 hours. This means a pleasant mix of sun and overcast.Should you favor a climate that's both dry and comfortably warm, June, July and August typically offer the most agreeable circumstances. If you're seeking pleasant, dry and sunny weather somewhere else in the world, our weather planner can help you explore other options.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit Finland, check out our Seinäjoki's climate page.
Seinäjoki Temperature in September
Min Temperature
6°C (43°F)
Max Temperature
15°C (59°F)
Chance of Rain
55%
Precipitation
60 mm (2.4 in)
Rainy days
17 days
Sunshine
135 hours *
Percentage Sunshine
*
Daily Historical Temperatures
50-year average (1976-2025)
Based on our historical records, temperatures in Seinäjoki typically drop from around 16°C (61°F) at the start of September to approximately 11°C (52°F) by the end. Nights are cold, with lows typically ranging from 3°C (37°F) to 8°C (46°F).
Average temperatures in September
Daily Historical Precipitation
50-year average (1976-2025)
Average daily rainfall for each day of the month based on long-term records.
Average precipitation in September
Historical weather for Seinäjoki in September
Browse day-by-day weather records for Seinäjoki spanning 51 years. Select any month and year to see actual temperatures, rainfall, and conditions recorded on each day.
Seinäjoki historical weather extremes in September
Based on 49 years of weather observations (1976-2025), these are the most extreme conditions recorded in Seinäjoki.
- The hottest September day on record in Seinäjoki reached 26°C (79°F) (September 5, 2024).
- The coldest September day was on September 30, 1997, with a maximum of 1°C (34°F).
- Seinäjoki registered its coldest September night on September 28, 1986, with temperatures dropping to -7°C (19°F).
- The wettest day in September Seinäjoki was on September 18, 2015 with 31 mm (1.2 in) of precipitation.
Best Places in Finland in September
Find out more about the weather in Finland and which places have the best travel conditions in this month. See all of Finland in September →
perfect weather
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tolerable
unpleasant
poor
What to Wear in Seinäjoki in September
The weather can swing between comfortable and chilly in September, so flexibility is key. Pack a variety of tops, at least one warm layer, and both shorts and long pants. This gives you options no matter what the day brings. Wet weather is likely, so pack waterproof gear for multiple rainy days. Sunglasses could come in handy during the sunnier parts of your trip.What To Do in Seinäjoki in September
We rated the following activities from 1 (least suitable) to 10 (best) to do.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit Finland, check out our Seinäjoki's climate page.
See the full Seinäjoki climate overview or explore weather in Finland.
