Raisio weather in September

In September, Raisio sees average daytime highs of 15°C and overnight lows near 8°C, with 58 mm of rain across 9.5 wet days and about 12.6 hours of daylight. It is the 4th-warmest and 5th-wettest month of the year here.

Highs ease over the month, from about 18°C in the first days to 13°C by the end. The sky is clear or mostly clear about 20% of the time in September, and the air most often feels dry.

Daylight stretches from about 14 hours at the start of September to 11 h 12 min by month's end. Set against the rest of the year, September is Raisio's 6th-clearest and 7th-windiest month. For the whole year in context, see Raisio's year-round climate.

Daytime high
15°
4th warmest
Overnight low
9th coldest
Rainfall
58 mm
9.5 wet days
Daylight
12 h 30 min
6:09 AM – 6:42 PM
Cloud cover
66%
6th clearest
Wind
12 km/h
7th windiest
Solar energy
2.58 kWh/m²
Travel score
4.5
out of 10

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 18°C in the first days to 13°C by the end.

A typical September day in Raisio reaches about 15°C in the afternoon and slips back to 8°C overnight — a 8°C spread between the day's warmth and the night's chill. On most days the high lands between 11°C and 19°C. Set against its neighbours, September runs about 5°C cooler than August and about 7°C warmer than October.

10°20°151015202530
Avg high (°C)Avg low (°C)
11810
21810
3189
4179
5179
6179
7179
8179
9179
10168
11168
12168
13168
14168
15158
16157
17157
18157
19157
20147
21147
22147
23146
24146
25136
26136
27136
28136
29136
30126

How September really feels in Raisio

Once humidity and wind are folded in, September 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

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

Raisio weather by month

How September compares with the rest of the year at a glance. September is the 4th-warmest and 5th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan-1° / -6°4910.18.66.30.0
Feb-2° / -7°378.57.28.60.0
Mar / -5°368.25.711.30.0
Apr / -0°3381.814.21.7
May15° / 418.90.116.94.6
Jun19° / 6810.8018.55.9
Jul22° / 12°8512.3017.86.2
Aug20° / 11°8012.6015.46.0
Sep15° / 589.5012.64.5
Oct / 5910.40.69.71.6
Nov / -0°5510.93.47.10.0
Dec / -4°5611.66.85.50.0

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 20% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 19% of September, with mostly cloudy or overcast conditions the remaining 62%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
13565
23565
33565
43664
53664
63664
73664
83961
93961
103961
113961
123961
133961
144060
154159
164159
174159
184159
194060
204060
214060
223961
233961
243961
253862
263763
273763
283664
293664
303565

Chance of precipitation in September

Any precipitation

Raisio gets around 58 mm of rain over 9.5 wet days in September. 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 40% on the wettest days. The odds ease toward the end of the month.

0%10%20%30%40%50%151015202530
Rain chance (%)
140
240
339
439
538
637
737
836
936
1035
1135
1234
1333
1433
1532
1631
1731
1830
1929
2029
2129
2229
2329
2429
2529
2629
2730
2830
2931
3031

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, September lands in the dry band about 90% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)
175232
276222
377212
478211
579201
680191
781181
883161
985150
1086140
1187130
1288120
1390100
149190
159280
169370
179460
189460
199550
209640
219640
229640
239730
249730
259730
269730
279820
289820
299820
309820

Wind in September

Winds average 12 km/h in September.

Across September, 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.

051015151015202530
Wind speed (km/h)Feels
112calm
212calm
312calm
412calm
512calm
612calm
712light breeze
812light breeze
912light breeze
1012light breeze
1112light breeze
1212light breeze
1312light breeze
1412light breeze
1512light breeze
1612light breeze
1712light breeze
1812light breeze
1912light breeze
2012light breeze
2112light breeze
2212light breeze
2312light breeze
2412light breeze
2512light breeze
2613light breeze
2713light breeze
2813light breeze
2913light breeze
3013light breeze

Sunrise & sunset in September

DaylightNight

Daylight runs from about 14 hours at the start of September to 11 h 12 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 168 minutes over September. Sunrise moves from 5:32 AM to 6:44 AM, and sunset from 7:30 PM to 5:57 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
114.05:327:30
213.95:357:27
313.85:377:24
413.75:407:20
513.65:427:17
613.55:447:14
713.45:477:11
813.35:497:08
913.25:527:05
1013.15:547:01
1113.05:576:58
1212.95:596:55
1312.86:026:52
1412.76:046:48
1512.66:076:45
1612.56:096:42
1712.56:126:39
1812.46:146:36
1912.36:176:32
2012.26:196:29
2112.16:226:26
2212.06:246:23
2311.96:276:20
2411.86:296:16
2511.76:326:13
2611.66:346:10
2711.56:376:07
2811.46:396:03
2911.36:426:00
3011.26:445:57

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 2.58 kWh/m².

For context, solar energy here swings from a low near 0.15 kWh/m² to a high of 5.89 kWh/m² in June across the year — September's 2.58 kWh/m² falls in the middle.

01234151015202530
Solar energy (kWh/m²)Level
13.3Moderate
23.3Moderate
33.2Moderate
43.1Moderate
53.1Moderate
63.0Moderate
73.0Moderate
82.9Moderate
92.9Moderate
102.8Moderate
112.8Moderate
122.8Moderate
132.7Moderate
142.6Moderate
152.6Moderate
162.5Moderate
172.5Moderate
182.5Moderate
192.4Moderate
202.4Moderate
212.3Moderate
222.3Moderate
232.2Moderate
242.2Moderate
252.1Moderate
262.0Moderate
272.0Moderate
281.9Dim
291.9Dim
301.8Dim
Planning a trip in September

Is September a good time to visit Raisio?

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

4.5
Sightseeing
5th-best month of the year
0.6
Beach & pool
4th-best month of the year

September is a reasonable time to visit Raisio for sightseeing.

What to pack for Raisio in September

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

In September, Raisio sees daytime highs around 15°C and nights near 8°C. Worth packing: a warm layer and rain gear. About 10 days see rain.

a warm layerrain gear

Sea temperature near Raisio in September

The nearest coast averages about 14°C in September — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 32 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 Raisio in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 2. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Raisio 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 Raisio?

Raisio sits at 60.5°N, 22.2°E, 11 m above sea level, in Finland. The nearest listed city is Turku, 7.0 km away.

Rauma

Topography around Raisio

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

Within 3 km, the terrain around Raisio has only modest variations in elevation — a maximum elevation change of 58 m around an average of 23 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 78 m; within 80 km, significant variations in elevation — a maximum elevation change of 273 m.

The land around Raisio is covered by trees (57%) and artificial surfaces (20%) within 3 km, trees (50%) within 16 km, and trees (45%) and water (38%) within 80 km.

3 km
58 m
16 km
78 m
80 km
273 m
treesgrasslandcroplandartificial surfaceswaterwetland
September weather nearby: Turku 7.0 km · Naantali 8.0 km · Kaarina 14 km · Lieto 16 km · Väståboland 22 km · Salo 54 km · Loimaa 63 km · Rauma 80 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 Raisio (60.4859°, 22.1689°, 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).