Naantali weather in August

In August, Naantali sees average daytime highs of 20°C and overnight lows near 12°C, with 75 mm of rain across 12.2 wet days and about 15.4 hours of daylight. It is the 2nd-warmest and 2nd-wettest month of the year here.

Highs ease over the month, from about 21°C in the first days to 18°C by the end. The sky is clear or mostly clear about 25% of the time in August, and the air most often feels dry.

Daylight stretches from about 16 h 42 min at the start of August to 14 h 06 min by month's end. Set against the rest of the year, August is Naantali's 4th-clearest and 11th-windiest month. For the whole year in context, see Naantali's year-round climate.

Daytime high
20°
2nd warmest
Overnight low
12°
11th coldest
Rainfall
75 mm
12.2 wet days
Daylight
15 h 24 min
4:53 AM – 8:19 PM
Cloud cover
62%
4th clearest
Wind
13 km/h
11th windiest
Solar energy
4.32 kWh/m²
Travel score
5.9
out of 10

Temperature in August

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 21°C in the first days to 18°C by the end.

A typical August day in Naantali reaches about 20°C in the afternoon and slips back to 12°C overnight — a 7°C spread between the day's warmth and the night's chill. On most days the high lands between 16°C and 24°C. Set against its neighbours, August runs about 1°C cooler than July and about 5°C warmer than September.

10°15°20°25°30°151015202531
Avg high (°C)Avg low (°C)
12114
22114
32114
42114
52113
62113
72113
82113
92113
102113
112113
122013
132013
142013
152013
162013
172012
182012
192012
201912
211912
221912
231912
241912
251912
261912
271811
281811
291811
301811
311811

How August really feels in Naantali

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.

Naantali weather by month

How August compares with the rest of the year at a glance. August is the 2nd-warmest and 2nd-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan-1° / -5°4810.28.36.30.0
Feb-2° / -7°368.47.28.60.0
Mar / -4°348.25.411.30.0
Apr / 327.71.814.21.2
May13° / 398.60.116.94.0
Jun18° / 10°6210.5018.55.6
Jul21° / 13°7611.8017.86.2
Aug20° / 12°7512.2015.45.9
Sep15° / 589.7012.64.4
Oct / 62110.69.71.7
Nov / 5811.33.27.10.1
Dec / -3°5712.36.85.50.0

Cloud cover in August

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 25% of the time in August.

Beyond those clear spells, partly cloudy skies cover about 20% of August, with mostly cloudy or overcast conditions the remaining 55%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
15248
25149
35149
45050
55050
65050
74951
84852
94852
104753
114753
124753
134654
144654
154654
164555
174555
184555
194357
204357
214357
224258
234258
244159
254159
263961
273961
283961
293862
303862
313862

Chance of precipitation in August

Any precipitation

Naantali gets around 75 mm of rain over 12.2 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 39% and peaks near 41% on the wettest days.

0%10%20%30%40%50%151015202531
Rain chance (%)
138
238
338
438
538
638
738
838
938
1038
1139
1239
1339
1439
1539
1639
1739
1840
1940
2040
2140
2241
2341
2441
2541
2641
2741
2841
2941
3041
3140

Humidity in August

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, August lands in the dry band about 57% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)
14635163
24634163
34734163
44833163
54833163
64933162
75033152
85132152
95232142
105332141
115333131
125433121
135533111
145533111
155633101
16573391
17573391
18593380
19593380
20603370
21613270
22613270
23623260
24633160
25643060
26653050
27662950
28672850
29692740
30702640
31722530

Wind in August

Winds average 13 km/h in August.

Across August, daily wind ranges from about 12 km/h on the calmest days to 13 km/h at its breeziest. It stays fairly steady from day to day.

05101520151015202531
Wind speed (km/h)Feels
112light breeze
212light breeze
312light breeze
412light breeze
512light breeze
612light breeze
712light breeze
813light breeze
913light breeze
1013light breeze
1113light breeze
1213light breeze
1313light breeze
1413light breeze
1513light breeze
1613light breeze
1713light breeze
1813light breeze
1913light breeze
2013light breeze
2113light breeze
2213light breeze
2313light breeze
2413light breeze
2513light breeze
2613light breeze
2713light breeze
2813light breeze
2913light breeze
3013light breeze
3113light breeze

Sunrise & sunset in August

DaylightNight

Daylight runs from about 16 h 42 min at the start of August to 14 h 06 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 156 minutes over August. Sunrise moves from 4:16 AM to 5:30 AM, and sunset from 9:00 PM to 7:34 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
116.74:169:00
216.74:188:58
316.64:218:55
416.54:238:52
516.44:258:50
616.34:288:47
716.24:308:45
816.24:338:42
916.14:358:39
1016.04:388:36
1115.94:408:34
1215.84:438:31
1315.74:458:28
1415.64:488:25
1515.54:508:22
1615.44:538:19
1715.44:558:16
1815.34:588:13
1915.25:008:10
2015.15:038:07
2115.05:058:04
2214.95:088:01
2314.85:107:58
2414.75:137:55
2514.65:157:52
2614.55:187:49
2714.45:207:46
2814.35:237:43
2914.25:257:40
3014.25:287:37
3114.15:307:34

Solar energy in August

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in August, about 4.32 kWh/m².

For context, solar energy here swings from a low near 0.16 kWh/m² to a high of 5.97 kWh/m² in June across the year — August's 4.32 kWh/m² falls in the middle.

0246151015202531
Solar energy (kWh/m²)Level
15.1Bright
25.1Bright
35.0Bright
45.0Bright
54.9Bright
64.9Bright
74.8Bright
84.8Bright
94.7Bright
104.7Bright
114.6Bright
124.6Bright
134.5Bright
144.5Bright
154.4Bright
164.3Bright
174.3Bright
184.2Bright
194.2Bright
204.1Bright
214.0Bright
224.0Moderate
233.9Moderate
243.9Moderate
253.8Moderate
263.7Moderate
273.6Moderate
283.6Moderate
293.5Moderate
303.5Moderate
313.4Moderate
Planning a trip in August

Is August a good time to visit Naantali?

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

5.9
Sightseeing
2nd-best month of the year
3.0
Beach & pool
2nd-best month of the year

August is a reasonable time to visit Naantali for sightseeing.

What to pack for Naantali in August

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

In August, Naantali sees daytime highs around 20°C and nights near 12°C. Worth packing: rain gear. About 12 days see rain.

rain gear

Sea temperature near Naantali 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 at the nearest coast (about 24 km away) is warmest in August at about 17°C and coldest in March near 1°C.

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

0°10°20°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshing
Sea temperature (°C)Comfort
Jan2Bracing
Feb1Bracing
Mar1Bracing
Apr2Bracing
May6Bracing
Jun11Bracing
Jul16Cool
Aug17Cool
Sep14Bracing
Oct10Bracing
Nov7Bracing
Dec4Bracing

UV index in Naantali 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 Naantali peaks around June 16 at about 5 (high) — a little sun protection helps at midday. It bottoms out near December 19 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 16UV 5Dec 19UV 0
UV index (midday)Level
Jan0Low
Feb1Low
Mar2Low
Apr3Moderate
May4Moderate
Jun5High
Jul4Moderate
Aug4Moderate
Sep2Moderate
Oct1Low
Nov0Low
Dec0Low
Location & terrain

Where is Naantali?

Naantali sits at 60.5°N, 22.0°E, 9 m above sea level, in Finland. The nearest listed city is Raisio, 8.0 km away.

LoimaaRauma

Topography around Naantali

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

Within 3 km, the terrain around Naantali has only modest variations in elevation — a maximum elevation change of 49 m around an average of 13 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 73 m; within 80 km, significant variations in elevation — a maximum elevation change of 263 m.

The land around Naantali is covered by trees (45%) and water (28%) within 3 km, trees (48%) and water (25%) within 16 km, and water (43%) and trees (41%) within 80 km.

3 km
49 m
16 km
73 m
80 km
263 m
treesgrasslandcroplandartificial surfacesbare terrainwaterwetland
August weather nearby: Raisio 8.0 km · Turku 14 km · Kaarina 20 km · Väståboland 24 km · Lieto 24 km · Salo 62 km · Loimaa 70 km · Rauma 78 km

Finland travel facts

Travel advisory
Level 1
Exercise Normal Precautions
Power plugs
Type C / F
230 V · 50 Hz
Prices
≈ 85% of US
price level, 2025
GDP per capita
$56,149
2025
Happiness
7.8 / 10
World Happiness, 2025
Safe drinking water
100%
of population, 2024
Homicide rate
1
per 100k, 2023
Road deaths
3.9
per 100k/yr, 2019
Income group
High
World Bank
English
Very high
EF EPI 603
Religion
Lutheran 67%none 31%other 2%Greek Orthodox 1%

Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.

Data sources

Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Naantali (60.4674°, 22.0243°, elevation 9 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).