World Resorts Finland Seinajoki Weather

Seinajoki weather in September

Weather in Seinajoki: September

Average day temperature: 57.4°F
Average night temperature: 47.2°F
Sea water temperature: 55.9°F
Number of sunny days: 7 days
Day length: 11.5 - 14.4 hours
Number of rainy days: 3 days
Precipitation totals: 1.8 in.

Air temperature in September, °F

Show year:
2026
2025
2024

The highest day temperature during September of 2026 was 66°F. At the same time the lowest night temperature was 41°F. Daily and nightly averages during September were 57.2°F and 48.8°F.

Sea water temperature in Seinajoki in September, °F

Show year:
2026
2025
2024

The average sea water temperature in September of 2026 was 56.8°F. The highest and lowest sea temperatures during the month were 61.0°F and 52.9°F.

Sunny, partly cloudy and cloudy days

Mostly all days in September are cloudy but sunny and partly cloudy days are also possible.

Precipitation total in September, in.

Precipitation total value in Seinajoki in September is 1.9 in. Other months of the year show relatively similar values.

Wind speed in September, mph

The average wind speed value in September is 6.6 mph It makes September one of the least windy months of the year.

Average sunny hours

This chart shows average number of hours during the day when sunlight can reach the ground. It depends on day length and cloudiness during the day. The average number of sunny hours in September is: 5.5.

Best time for vacation in Seinajoki

Sunniest months:
May 11 days
July 11 days
June 10 days
Warmest months:
July 70.0 °F
August 66.4 °F
June 65.3 °F
Warmest sea temp:
August 61.9 °F
July 61.1 °F
September 55.9 °F
Coldest months:
January 22.1 °F
February 25.2 °F
December 28.0 °F
Rainiest months:
July 5 days
August 5 days
September 3 days
Windiest months:
March 8.4 mph
December 7.9 mph
May 7.7 mph

Seinajoki on a weather map

Seinajoki
+50°F
E 15 mph
Feels like: +45°F
Precip.: 14%
Places in Finland:
Name
°F
+52°F
+50°F
+50°F
+54°F
+50°F
+50°F
+50°F
+52°F
+45°F
+50°F
+50°F
+54°F
+52°F
+52°F
+50°F
24 Hours Forecast
Seinajoki
Local time: 21:06
October 07, wednesday
0000
48°F
E
13 mph
0300
46°F
E
11 mph
0600
46°F
E
11 mph
0900
45°F
E
9 mph
1200
50°F
E
11 mph
1500
52°F
E
9 mph
1800
46°F
E
8 mph
2100
43°F
NE
6 mph
Units of measurement: °C / °F