World Resorts Finland Porvoo Weather

Porvoo weather in September

Weather in Porvoo: September

Average day temperature: 58.3°F
Average night temperature: 54.1°F
Sea water temperature: 58.5°F
Number of sunny days: 10 days
Day length: 11.5 - 14.2 hours
Number of rainy days: 4 days
Precipitation totals: 2.1 in.

Air temperature in September, °F

Show year:
2025
2024
2023

The highest day temperature during September of 2025 was 65°F. At the same time the lowest night temperature was 42°F. Daily and nightly averages during September were 59.0°F and 56.4°F.

Sea water temperature in Porvoo in September, °F

Show year:
2025
2024
2023

The average sea water temperature in September of 2025 was 59.1°F. The highest and lowest sea temperatures during the month were 64.0°F and 52.3°F.

Sunny, partly cloudy and cloudy days

Number of sunny, partly cloudy and cloudy days in September is almost equal.

Precipitation total in September, in.

Precipitation total value in Porvoo in September is 2.1 in. Other months of the year show relatively similar values.

Wind speed in September, mph

The average wind speed value in September is 13.2 mph

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: 7.0.

Best time for vacation in Porvoo

Sunniest months:
June 15 days
July 15 days
May 13 days
Warmest months:
July 66.2 °F
August 65.8 °F
June 59.9 °F
Warmest sea temp:
August 63.7 °F
July 63.0 °F
September 58.5 °F
Coldest months:
January 27.9 °F
February 28.0 °F
March 33.0 °F
Rainiest months:
August 5 days
October 4 days
December 4 days
Windiest months:
December 14.5 mph
October 14.3 mph
November 14.0 mph

Porvoo on a weather map

Porvoo
+41°F
NE 7 mph
Feels like: +36°F
Precip.: 0%
Places in Finland:
Name
°F
+39°F
+39°F
+32°F
+41°F
+37°F
+37°F
+36°F
+39°F
+18°F
+37°F
+41°F
+39°F
+39°F
+36°F
24 Hours Forecast
Porvoo
Local time: 11:19
December 05, friday
1200
41°F
NE
7 mph
1500
41°F
N
6 mph
1800
41°F
N
6 mph
2100
41°F
NW
7 mph
December 06, saturday
0000
41°F
NW
8 mph
0300
41°F
NW
10 mph
0600
41°F
NW
11 mph
0900
41°F
W
14 mph
Units of measurement: °C / °F