Raseborg weather in September

In September, Raseborg sees average daytime highs of 15°C and overnight lows near 9°C, with 53 mm of rain across 10.1 wet days and about 12.6 hours of daylight. It is the 4th-warmest and 7th-wettest month of the year here.

Highs ease over the month, from about 17°C in the first days to 13°C by the end. The sky is clear or mostly clear about 21% of the time in September, and the air most often feels dry.

Daylight stretches from about 13 h 54 min at the start of September to 11 h 12 min by month's end. Set against the rest of the year, September is Raseborg's 6th-clearest and 7th-windiest month. For the whole year in context, see Raseborg's year-round climate.

Daytime high
15°
4th warmest
Overnight low
9th coldest
Rainfall
53 mm
10.1 wet days
Daylight
12 h 30 min
6:05 AM – 6:37 PM
Cloud cover
66%
6th clearest
Wind
16 km/h
7th windiest
Solar energy
2.59 kWh/m²
Travel score
4.5
out of 10

Raseborg is town in the region of Uusimaa in Finland.

Density
22/km²
people per km²
Founded
2009

Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 17°C in the first days to 13°C by the end.

A typical September day in Raseborg reaches about 15°C in the afternoon and slips back to 9°C overnight — a 6°C spread between the day's warmth and the night's chill. On most days the high lands between 11°C and 18°C. Set against its neighbours, September runs about 5°C cooler than August and about 6°C warmer than October.

10°15°20°25°151015202530
Avg high (°C)Avg low (°C)
11811
21811
31711
41711
51710
61710
71710
81710
91610
101610
111610
12169
13169
14159
15159
16159
17159
18159
19158
20148
21148
22148
23148
24148
25138
26137
27137
28137
29137
30127

How September really feels in Raseborg

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.

Raseborg weather by month

How September compares with the rest of the year at a glance. September is the 4th-warmest and 7th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan-1° / -5°5110.98.96.40.0
Feb-2° / -6°4097.98.60.0
Mar / -4°378.15.711.30.0
Apr / 348.31.914.11.1
May13° / 378.10.116.74.0
Jun18° / 10°539.4018.35.7
Jul21° / 13°579.5017.76.6
Aug20° / 13°6611.4015.46.1
Sep15° / 5310.1012.64.5
Oct / 6510.90.59.81.8
Nov / 63123.87.20.1
Dec / -2°5912.875.70.0

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 21% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 17% of September, with mostly cloudy or overcast conditions the remaining 61%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
13763
23664
33763
43763
53862
63961
74060
84060
94159
104159
114159
124159
134159
144258
154159
164159
174159
184159
194060
204060
213961
223862
233862
243763
253763
263763
273664
283664
293565
303565

Chance of precipitation in September

Any precipitation

Raseborg gets around 53 mm of rain over 10.1 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 34% and peaks near 36% on the wettest days.

0%10%20%30%40%50%151015202530
Rain chance (%)
136
236
336
436
535
635
735
835
935
1035
1135
1235
1334
1434
1534
1634
1733
1833
1933
2033
2133
2233
2332
2432
2532
2632
2733
2833
2933
3033

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 88% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)
172253
273243
374242
475232
576222
678211
779201
880191
981181
1082171
1184160
1286140
1387130
1488120
1589110
169190
179280
189370
199460
209550
219550
229640
239640
249730
259730
269730
279820
289820
299820
309820

Wind in September

Winds average 16 km/h in September.

Across September, daily wind ranges from about 15 km/h on the calmest days to 17 km/h at its breeziest. It stays fairly steady from day to day.

05101520151015202530
Wind speed (km/h)Feels
115light breeze
215light breeze
315light breeze
415light breeze
515light breeze
615light breeze
715light breeze
816light breeze
916light breeze
1016light breeze
1116light breeze
1216light breeze
1316light breeze
1416light breeze
1516light breeze
1616light breeze
1716light breeze
1816light breeze
1916light breeze
2016light breeze
2116light breeze
2216light breeze
2316light breeze
2416light breeze
2516light breeze
2617light breeze
2717light breeze
2817light breeze
2917light breeze
3017light breeze

Sunrise & sunset in September

DaylightNight

Daylight runs from about 13 h 54 min 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 162 minutes over September. Sunrise moves from 5:28 AM to 6:39 AM, and sunset from 7:24 PM to 5:53 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
113.95:287:24
213.85:317:21
313.75:337:17
413.65:357:14
513.65:387:11
613.55:407:08
713.45:437:05
813.35:457:02
913.25:486:59
1013.15:506:56
1113.05:526:52
1212.95:556:49
1312.85:576:46
1412.76:006:43
1512.66:026:40
1612.56:056:37
1712.46:076:33
1812.36:096:30
1912.36:126:27
2012.26:146:24
2112.16:176:21
2212.06:196:18
2311.96:216:14
2411.86:246:11
2511.76:266:08
2611.66:296:05
2711.56:316:02
2811.46:345:59
2911.36:365:56
3011.26:395:53

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 2.59 kWh/m².

For context, solar energy here swings from a low near 0.17 kWh/m² to a high of 5.95 kWh/m² in June across the year — September's 2.59 kWh/m² falls in the middle.

01234151015202530
Solar energy (kWh/m²)Level
13.3Moderate
23.3Moderate
33.2Moderate
43.2Moderate
53.1Moderate
63.1Moderate
73.0Moderate
83.0Moderate
92.9Moderate
102.9Moderate
112.8Moderate
122.8Moderate
132.7Moderate
142.7Moderate
152.6Moderate
162.6Moderate
172.5Moderate
182.5Moderate
192.4Moderate
202.4Moderate
212.3Moderate
222.3Moderate
232.2Moderate
242.2Moderate
252.1Moderate
262.1Moderate
272.0Moderate
282.0Dim
291.9Dim
301.9Dim
Planning a trip in September

Is September a good time to visit Raseborg?

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

4.5
Sightseeing
4th-best month of the year
0.5
Beach & pool
4th-best month of the year

September is a reasonable time to visit Raseborg for sightseeing.

What to pack for Raseborg in September

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

In September, Raseborg sees daytime highs around 15°C and nights near 9°C. Worth packing: a warm layer and rain gear. About 10 days see rain.

a warm layerrain gear

Sea temperature near Raseborg in September

The nearest coast averages about 15°C in September — 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 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
Jan3Bracing
Feb1Bracing
Mar1Bracing
Apr2Bracing
May6Bracing
Jun11Bracing
Jul16Cool
Aug17Cool
Sep15Bracing
Oct11Bracing
Nov8Bracing
Dec5Bracing

UV index in Raseborg in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 3. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Raseborg peaks around June 17 at about 5 (high) — a little sun protection helps at midday. It bottoms out near January 1 at about 0 (low).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighModerateLowJun 17UV 5Jan 1UV 0
UV index (midday)Level
Jan0Low
Feb1Low
Mar2Low
Apr3Moderate
May4Moderate
Jun5High
Jul5Moderate
Aug5Moderate
Sep3Moderate
Oct1Low
Nov0Low
Dec0Low
Location & terrain

Where is Raseborg?

Raseborg sits at 60.0°N, 23.4°E, 19 m above sea level, in Finland. The nearest listed city is Lohja, 46 km away.

VihtiVäståbolandOlari

Topography around Raseborg

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

Within 3 km, the terrain around Raseborg has only modest variations in elevation — a maximum elevation change of 53 m around an average of 11 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 90 m; within 80 km, significant variations in elevation — a maximum elevation change of 286 m.

The land around Raseborg is covered by trees (46%) and water (34%) within 3 km, trees (57%) and water (28%) within 16 km, and water (53%) and trees (36%) within 80 km.

3 km
53 m
16 km
90 m
80 km
286 m
treesgrasslandcroplandartificial surfaceswaterwetland
September weather nearby: Lohja 46 km · Salo 48 km · Kirkkonummi 58 km · Vihti 69 km · Espoonlahti 70 km · Espoo 72 km · Väståboland 73 km · Olari 75 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 Raseborg (59.9774°, 23.4397°, elevation 19 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).