Seinäjoki Weather in September
Average highs run from 18°C on September 1 to 11°C on September 30, and lows from 8°C to 3°C. Normal precipitation for the month is 52 mm over about 12 wet days.
September day by day
The normal high and low for each date, and the record, in °C.
- Normal low
- Normal high
- Record high
- Record low
September at a glance
- Average high
- 15°C
- Average low
- 5°C
- Precipitation
- 52 mm
- Record high
- 27°CSep 6, 1968
- Record low
- -9°CSep 28, 1986
- Daylight
- 14 h 25 min to 11 h 30 min
- Cloud cover
- 69%
- Humidity
- 89%
- Dew point
- 8°C
- Wind
- 7.9 km/h
Every day of the month
A wet day has at least 1 mm of precipitation in the reanalysis.
| Date | Normal high | Normal low | Record high | Record low | Chance wet |
|---|---|---|---|---|---|
| Sep 1 | 18°C | 8°C | 23°C 2019 | -2°C 1983 | 48% |
| Sep 2 | 18°C | 7°C | 24°C 2019 | -2°C 1980 | 48% |
| Sep 3 | 17°C | 7°C | 27°C 1963 | -4°C 1979 | 47% |
| Sep 4 | 18°C | 8°C | 27°C 1968 | -2°C 1959 | 45% |
| Sep 5 | 18°C | 8°C | 27°C 2024 | -3°C 1969 | 43% |
| Sep 6 | 17°C | 7°C | 27°C 1968 | -3°C 2000 | 44% |
| Sep 7 | 17°C | 7°C | 25°C 1968 | -3°C 1982 | 44% |
| Sep 8 | 16°C | 7°C | 25°C 2024 | -3°C 1996 | 45% |
| Sep 9 | 16°C | 6°C | 24°C 2024 | -5°C 1976 | 44% |
| Sep 10 | 16°C | 7°C | 24°C 2024 | -4°C 1989 | 44% |
| Sep 11 | 16°C | 6°C | 24°C 2025 | -4°C 1977 | 44% |
| Sep 12 | 16°C | 7°C | 22°C 2002 | -2°C 1973 | 43% |
| Sep 13 | 16°C | 5°C | 22°C 2006 | -5°C 1973 | 43% |
| Sep 14 | 15°C | 5°C | 22°C 1998 | -3°C 1982 | 44% |
| Sep 15 | 14°C | 5°C | 20°C 2009 | -4°C 1999 | 43% |
| Sep 16 | 14°C | 4°C | 19°C 1967 | -5°C 1995 | 41% |
| Sep 17 | 14°C | 3°C | 20°C 1961 | -6°C 1993 | 40% |
| Sep 18 | 14°C | 4°C | 21°C 2001 | -5°C 1976 | 39% |
| Sep 19 | 14°C | 5°C | 23°C 2001 | -5°C 1976 | 39% |
| Sep 20 | 13°C | 4°C | 21°C 2001 | -5°C 1996 | 38% |
| Sep 21 | 14°C | 5°C | 20°C 2023 | -4°C 1980 | 38% |
| Sep 22 | 14°C | 4°C | 22°C 2023 | -4°C 2021 | 38% |
| Sep 23 | 13°C | 5°C | 24°C 2006 | -6°C 1973 | 37% |
| Sep 24 | 13°C | 4°C | 19°C 1994 | -7°C 1973 | 37% |
| Sep 25 | 13°C | 3°C | 20°C 2007 | -8°C 1973 | 38% |
| Sep 26 | 13°C | 3°C | 20°C 2009 | -6°C 1973 | 38% |
| Sep 27 | 12°C | 4°C | 20°C 2005 | -7°C 1968 | 38% |
| Sep 28 | 12°C | 4°C | 19°C 2020 | -9°C 1986 | 40% |
| Sep 29 | 11°C | 3°C | 19°C 1981 | -6°C 1971 | 40% |
| Sep 30 | 11°C | 3°C | 18°C 2011 | -8°C 1978 | 41% |
Chance of rain
- Chance of a wet day
Sunrise and sunset
Times for 2026, local time (GMT+3).
- September 1
- sunrise 6:15 AM, sunset 8:40 PM
- September 30
- sunrise 7:33 AM, sunset 7:03 PM
Other months
Sources
Records: NOAA GHCN-Daily, station FIE00144407, every year on file, quality-flagged values removed. Cloud, humidity, wind and sunshine: NASA POWER (MERRA-2, CERES and GEWEX SRB), 1991-2020. The data was obtained from the National Aeronautics and Space Administration (NASA) Langley Research Center's Prediction Of Worldwide Energy Resources (POWER) project funded through the NASA Earth Science Division: POWER Daily API v2, accessed 2026-09-26. Sun and moon: computed with the NOAA solar equations and Meeus.