Mariehamn weather in August

In August, Mariehamn sees average daytime highs of 18°C and overnight lows near 16°C, with 55 mm of rain across 10.2 wet days and about 15.4 hours of daylight. It is the 1st-warmest and 4th-wettest month of the year here.

Highs ease over the month, from about 18°C in the first days to 16°C by the end. The sky is clear or mostly clear about 35% of the time in August, and the air most often feels comfortable.

Daylight stretches from about 16 h 42 min at the start of August to 14 hours by month's end. Set against the rest of the year, August is Mariehamn's 4th-clearest and 9th-windiest month. For the whole year in context, see Mariehamn's year-round climate.

Daytime high
18°
1st warmest
Overnight low
16°
12th coldest
Rainfall
55 mm
10.2 wet days
Daylight
15 h 24 min
5:03 AM – 8:26 PM
Cloud cover
56%
4th clearest
Wind
21 km/h
9th windiest
Solar energy
4.6 kWh/m²
Travel score
5.8
out of 10

Temperature in August

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 18°C in the first days to 16°C by the end.

A typical August day in Mariehamn reaches about 18°C in the afternoon and slips back to 16°C overnight — a 2°C spread between the day's warmth and the night's chill. On most days the high lands between 15°C and 20°C. Set against its neighbours, August runs on par with July and about 4°C warmer than September.

10°15°20°25°151015202531
Avg high (°C)Avg low (°C)
11817
21817
31817
41817
51817
61817
71817
81817
91817
101817
111817
121816
131816
141816
151816
161816
171816
181816
191716
201716
211716
221716
231716
241716
251715
261715
271715
281715
291615
301615
311615

How August really feels in Mariehamn

Once humidity and wind are folded in, August averages 0 days that feel above 32°C and 0 that feel at or below 0°C — the comfort signal a plain temperature reading hides.

Days feeling ≥ 32°C
0
heat index over the day's high
Days feeling ≤ C
0
wind chill below the day's low

August sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.

Mariehamn weather by month

How August compares with the rest of the year at a glance. August is the 1st-warmest and 4th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan / -1°4310.586.40.0
Feb / -2°297.76.58.60.0
Mar / -1°277.15.111.30.0
Apr / 296.91.714.20.0
May / 336.60.216.81.6
Jun13° / 11°497.5018.43.8
Jul17° / 15°487.6017.75.9
Aug18° / 16°5510.2015.45.8
Sep14° / 13°549.2012.64.1
Oct / 6211.80.49.81.9
Nov / 60132.97.10.4
Dec / 56136.15.60.0

Cloud cover in August

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 35% of the time in August.

Beyond those clear spells, partly cloudy skies cover about 19% of August, with mostly cloudy or overcast conditions the remaining 46%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
16040
26139
36040
46040
56040
65941
75941
85941
95743
105743
115743
125743
135545
145545
155545
165446
175347
185248
195248
205149
215050
225050
234852
244852
254852
264852
274753
284753
294753
304753
314753

Chance of precipitation in August

Any precipitation

Mariehamn gets around 55 mm of rain over 10.2 wet days in August. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 33% and peaks near 36% on the wettest days. The odds climb toward the end of the month.

0%10%20%30%40%50%151015202531
Rain chance (%)
127
228
328
428
529
629
729
830
930
1031
1131
1231
1332
1432
1532
1633
1733
1833
1934
2034
2135
2235
2336
2436
2536
2636
2736
2836
2936
3036
3136

Humidity in August

DryComfortableHumidMuggyOppressiveMiserable

Most of August feels comfortable — the stacked bands show each day's mix of comfort levels, read off the dew point.

By dew point, August lands in the comfortable band about 41% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
123442571
224442571
324432571
425432571
526432561
627432461
727422460
828422450
929422350
1030422350
1131422340
1231422240
1332422240
1433422130
1534422030
1636422030
1737421920
1838421920
1939411820
2040411810
2141401810
2242401710
2344391710
2445381610
2547381510
2648371400
2750371300
2852361200
2953361100
3055351000
315635900

Wind in August

Winds average 21 km/h in August.

Across August, daily wind ranges from about 20 km/h on the calmest days to 23 km/h at its breeziest. It stays fairly steady from day to day.

0102030151015202531
Wind speed (km/h)Feels
120light breeze
220breezy
320breezy
420breezy
520breezy
620breezy
721breezy
821breezy
921breezy
1021breezy
1121breezy
1221breezy
1321breezy
1421breezy
1521breezy
1621breezy
1722breezy
1822breezy
1922breezy
2022breezy
2122breezy
2222breezy
2322breezy
2422breezy
2523breezy
2623breezy
2723breezy
2823breezy
2923breezy
3023breezy
3123breezy

Sunrise & sunset in August

DaylightNight

Daylight runs from about 16 h 42 min at the start of August to 14 hours by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 162 minutes over August. Sunrise moves from 4:27 AM to 5:40 AM, and sunset from 9:06 PM to 7:41 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
116.74:279:06
216.64:299:04
316.54:319:01
416.44:348:59
516.34:368:56
616.24:388:53
716.24:418:51
816.14:438:48
916.04:468:45
1015.94:488:43
1115.84:518:40
1215.74:538:37
1315.74:558:34
1415.64:588:32
1515.55:008:29
1615.45:038:26
1715.35:058:23
1815.25:088:20
1915.15:108:17
2015.05:138:14
2114.95:158:11
2214.85:178:08
2314.85:208:05
2414.75:228:02
2514.65:257:59
2614.55:277:56
2714.45:307:53
2814.35:327:50
2914.25:357:47
3014.15:377:44
3114.05:407:41

Solar energy in August

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in August, about 4.6 kWh/m².

For context, solar energy here swings from a low near 0.18 kWh/m² to a high of 6.29 kWh/m² in June across the year — August's 4.6 kWh/m² falls in the middle.

0246151015202531
Solar energy (kWh/m²)Level
15.4Bright
25.4Bright
35.3Bright
45.3Bright
55.2Bright
65.2Bright
75.1Bright
85.1Bright
95.0Bright
105.0Bright
114.9Bright
124.8Bright
134.8Bright
144.7Bright
154.7Bright
164.6Bright
174.5Bright
184.5Bright
194.4Bright
204.3Bright
214.3Bright
224.2Bright
234.2Bright
244.1Bright
254.0Bright
264.0Moderate
273.9Moderate
283.8Moderate
293.8Moderate
303.7Moderate
313.6Moderate
Planning a trip in August

Is August a good time to visit Mariehamn?

Our two travel scores rate August for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).

5.8
Sightseeing
2nd-best month of the year
1.6
Beach & pool
1st-best month of the year

August is a reasonable time to visit Mariehamn for sightseeing.

What to pack for Mariehamn in August

From August's temperature range, rain chance, sun and wind — what's worth putting in the bag.

In August, Mariehamn sees daytime highs around 18°C and nights near 16°C. Worth packing: rain gear, sun protection and a windbreaker. About 10 days see rain.

rain gearsun protectiona windbreaker

Sea temperature near Mariehamn in August

The nearest coast averages about 17°C in August — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea offshore is warmest in August at about 17°C and coldest in February near 1°C.

The water stays below 20°C all year — cool enough that most swimmers want a wetsuit.

0°5°10°15°20°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshing
Sea temperature (°C)Comfort
Jan2Bracing
Feb1Bracing
Mar1Bracing
Apr3Bracing
May6Bracing
Jun11Bracing
Jul16Cool
Aug17Cool
Sep14Bracing
Oct10Bracing
Nov7Bracing
Dec4Bracing

UV index in Mariehamn in August

LowModerateHighVery highExtreme

Clear-sky midday UV in August peaks around 4 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Mariehamn peaks around June 18 at about 5 (high) — a little sun protection helps at midday. It bottoms out near December 20 at about 0 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 4 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateModerateLowJun 18UV 5Dec 20UV 0
UV index (midday)Level
Jan0Low
Feb1Low
Mar1Low
Apr3Moderate
May4Moderate
Jun5High
Jul5Moderate
Aug4Moderate
Sep3Moderate
Oct1Low
Nov0Low
Dec0Low
Location & terrain

Where is Mariehamn?

Mariehamn sits at 60.1°N, 19.9°E, 11 m above sea level, in Aland Islands. The nearest listed city is Norrtälje, 78 km away.

Topography around Mariehamn

How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Mariehamn.

Within 3 km, the terrain around Mariehamn has only modest variations in elevation — a maximum elevation change of 55 m around an average of 7 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 80 m; within 80 km, only modest variations in elevation — a maximum elevation change of 130 m.

The land around Mariehamn is covered by water (44%) and trees (32%) within 3 km, water (55%) and trees (31%) within 16 km, and water (86%) within 80 km.

3 km
55 m
16 km
80 m
80 km
130 m
treesgrasslandcroplandartificial surfaceswaterwetland
August weather nearby: Norrtälje 78 km · Åkersberga 114 km · Vallentuna 121 km · Gustavsberg 122 km · Naantali 122 km · Boo 126 km · Täby 127 km · Märsta 128 km

Data sources

Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Mariehamn (60.0973°, 19.9348°, elevation 11 m), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google. Sea temperatures are the NOAA OISST v2.1 1991–2020 monthly climatology (public domain), sampled at the nearest ocean point. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).