Annual mean 8°C · wettest around January · prevailing wind SW
Warmest
19.8 °C
Coldest
-0.6 °C
Wettest
29%
Windiest
8.7 m/s
Prevailing
SW
7.0 m/s average
When this place is good five ratings · thirty-six ten-day sections · click a cell to read it
never good
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Every reading
bars actual · line feels-like, °Cchance of rain, %wind speed, m/ssky covered, %
The average temperature in Mariehamn over the whole year is 8°C. July is the hottest month, with highs of about 19°C; February is the coldest, with lows of about -0°C. Mariehamn has no sharply defined rainy season: the chance of rain on a given day runs from 11% in May, the driest month, to 22% in January, the wettest. Winds in Mariehamn are highest in January, averaging 7.8 m/s (28 km/h), and lightest in July, at 5.4 m/s (19 km/h). The prevailing wind is from the SW. The clearest skies in Mariehamn come in June, when the sky is typically 41% covered; January is the cloudiest month, at 78%.
Month by month Mariehamn climate by month: average temperatures year round · click a month to read it
Month
High
Low
Feels like
Chance of rain
Cloud
Wind
Being outside
Sun
Walking
January
0°C
0°C
-7°C
22%
78%
7.8 m/s
0
0
0
February
0°C
-0°C
-7°C
19%
69%
7.3 m/s
0
0
0
March
2°C
0°C
-5°C
15%
61%
6.8 m/s
0
0
1
April
5°C
3°C
-1°C
13%
50%
6.1 m/s
0
0
6
May
10°C
7°C
4°C
11%
43%
5.6 m/s
6
0
32
June
16°C
13°C
12°C
12%
41%
5.6 m/s
30
2
68
July
19°C
16°C
15°C
12%
41%
5.4 m/s
53
5
74
August
18°C
16°C
15°C
17%
45%
6.3 m/s
50
1
77
September
14°C
12°C
10°C
16%
53%
6.3 m/s
16
0
68
October
9°C
8°C
3°C
13%
68%
7.6 m/s
0
0
24
November
5°C
5°C
-2°C
19%
76%
7.4 m/s
0
0
5
December
2°C
2°C
-5°C
21%
77%
7.6 m/s
0
0
0
High and low are the warmest and coolest of four readings a day — midnight, 6am, noon and 6pm — so a true overnight low can sit a degree or two under them. Chance of rain, cloud and wind are the day’s average; feels-like and the three ratings (each out of 100: Good from 55, Ideal from 80) are read at midday.
Seasons, and the year in short Mariehamn weather by season
Year round, Mariehamn has days of about 0°C at their warmest in January, its coolest month, and 19°C in July, its warmest; the coolest hours of the day run from -0°C to 16°C through the year, and the average temperature over the year is 8°C around the clock. Rain is most likely around January and least likely around May. Every figure here is a decade of observations blended into one representative year, so it reads as what this date is usually like, not a forecast for one particular day.
Mariehamn weather in winterDecember to February
High 1°CLow 0°CRain 21%
Winter in Mariehamn has typical daily highs of about 1°C and lows of about 0°C, with a 21% chance of rain on a given day.
Mariehamn weather in springMarch to May
High 6°CLow 3°CRain 13%
Spring in Mariehamn has typical daily highs of about 6°C and lows of about 3°C, with a 13% chance of rain on a given day.
Mariehamn weather in summerJune to August
High 17°CLow 15°CRain 14%
Summer in Mariehamn has typical daily highs of about 17°C and lows of about 15°C, with a 14% chance of rain on a given day.
Mariehamn weather in autumnSeptember to November
High 10°CLow 8°CRain 16%
Autumn in Mariehamn has typical daily highs of about 10°C and lows of about 8°C, with a 16% chance of rain on a given day.
When is the rainy season in Mariehamn?
Mariehamn has no sharply defined rainy season: the chance of rain on a given day runs from 11% in May, the driest month, to 22% in January, the wettest.
What time of year is Mariehamn windiest?
Winds in Mariehamn are highest in January, averaging 7.8 m/s (28 km/h), and lightest in July, at 5.4 m/s (19 km/h). The prevailing wind is from the SW.
What is the average temperature in Mariehamn year round?
The average temperature in Mariehamn over the whole year is 8°C. July is the hottest month, with highs of about 19°C; February is the coldest, with lows of about -0°C.