Jakobstad weather in September

In September, Jakobstad sees average daytime highs of 13°C and overnight lows near 8°C, with 58 mm of rain across 10.5 wet days and about 12.7 hours of daylight. It is the 4th-warmest and 3rd-wettest month of the year here.

Highs ease over the month, from about 15°C in the first days to 11°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 14 h 18 min at the start of September to 11 h 06 min by month's end. Set against the rest of the year, September is Jakobstad's 6th-clearest and 6th-windiest month. For the whole year in context, see Jakobstad's year-round climate.

Daytime high
13°
4th warmest
Overnight low
9th coldest
Rainfall
58 mm
10.5 wet days
Daylight
12 h 36 min
6:05 AM – 6:42 PM
Cloud cover
67%
6th clearest
Wind
17 km/h
6th windiest
Solar energy
2.28 kWh/m²
Travel score
3.6
out of 10
Air quality
Excellent
PM10 11.7 µg/m³ · 2019

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 15°C in the first days to 11°C by the end.

A typical September day in Jakobstad reaches about 13°C in the afternoon and slips back to 8°C overnight — a 5°C spread between the day's warmth and the night's chill. On most days the high lands between 9°C and 17°C. Set against its neighbours, September runs about 5°C cooler than August and about 6°C warmer than October.

10°15°20°151015202530
Avg high (°C)Avg low (°C)
11611
21610
31510
41510
51510
61510
71510
81510
9149
10149
11149
12149
13149
14139
15138
16138
17138
18138
19128
20128
21128
22127
23127
24127
25117
26117
27117
28117
29116
30106

How September really feels in Jakobstad

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.

Jakobstad weather by month

How September compares with the rest of the year at a glance. September is the 4th-warmest and 3rd-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan-3° / -7°339.29.25.10.0
Feb-4° / -9°277.17.380.0
Mar-0° / -6°287.37.111.20.0
Apr / -1°317.33.514.50.3
May10° / 438.30.317.72.4
Jun15° / 519.6019.94.4
Jul19° / 13°6811.40195.8
Aug18° / 12°6811.20165.6
Sep13° / 5810.5012.73.6
Oct / 5710.91.89.40.8
Nov / -1°5011.16.16.20.0
Dec-1° / -4°4410.78.24.10.0

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 63%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
13961
24060
34060
43961
53961
64060
74060
84060
94159
104159
114060
124060
133961
143961
153961
163961
173961
183862
193862
203763
213763
223664
233466
243466
253466
263367
273268
283268
293268
303169

Chance of precipitation in September

Any precipitation

Jakobstad gets around 58 mm of rain over 10.5 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 35% and peaks near 36% on the wettest days.

0%10%20%30%40%50%151015202530
Rain chance (%)
135
235
335
435
535
635
735
835
936
1036
1136
1236
1336
1436
1536
1636
1736
1836
1935
2035
2135
2235
2335
2435
2534
2635
2735
2835
2935
3035

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 96% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)
185141
286131
389110
490100
59190
69280
79280
89370
99460
109550
119550
129640
139640
149730
159730
169820
179820
189820
199910
209910
219910
229910
239910
2410000
2510000
2610000
2710000
2810000
2910000
3010000

Wind in September

Winds average 17 km/h in September.

Across September, daily wind ranges from about 16 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
116light breeze
216light breeze
316light breeze
416light breeze
516light breeze
616light breeze
716light breeze
816light breeze
916light breeze
1016light breeze
1116light breeze
1216light breeze
1316light breeze
1416light breeze
1517light breeze
1617light breeze
1717light breeze
1817light breeze
1917light breeze
2017light breeze
2117light breeze
2217light breeze
2317light breeze
2417light breeze
2517light breeze
2617light breeze
2717light breeze
2817light breeze
2917light breeze
3017light breeze

Sunrise & sunset in September

DaylightNight

Daylight runs from about 14 h 18 min at the start of September to 11 h 06 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 192 minutes over September. Sunrise moves from 5:21 AM to 6:45 AM, and sunset from 7:37 PM to 5:52 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
114.35:217:37
214.15:247:33
314.05:277:29
413.95:307:26
513.85:337:22
613.75:367:19
713.65:397:15
813.55:427:11
913.45:457:08
1013.35:477:04
1113.25:507:00
1213.15:536:57
1313.05:566:53
1412.85:596:50
1512.76:026:46
1612.66:056:42
1712.56:086:39
1812.46:116:35
1912.36:136:31
2012.26:166:28
2112.16:196:24
2212.06:226:20
2311.96:256:17
2411.86:286:13
2511.66:316:10
2611.56:346:06
2711.46:376:02
2811.36:405:59
2911.26:425:55
3011.16:455:52

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 2.28 kWh/m².

For context, solar energy here swings from a low near 0.05 kWh/m² to a high of 5.88 kWh/m² in June across the year — September's 2.28 kWh/m² falls in the middle.

01234151015202530
Solar energy (kWh/m²)Level
13.1Moderate
23.0Moderate
33.0Moderate
42.9Moderate
52.9Moderate
62.8Moderate
72.7Moderate
82.7Moderate
92.6Moderate
102.6Moderate
112.5Moderate
122.5Moderate
132.4Moderate
142.4Moderate
152.3Moderate
162.3Moderate
172.2Moderate
182.1Moderate
192.1Moderate
202.0Moderate
212.0Dim
221.9Dim
231.9Dim
241.8Dim
251.8Dim
261.7Dim
271.6Dim
281.6Dim
291.6Dim
301.5Dim
Planning a trip in September

Is September a good time to visit Jakobstad?

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

3.6
Sightseeing
4th-best month of the year
0.1
Beach & pool
4th-best month of the year

September is a weaker month for outdoor sightseeing in Jakobstad.

What to pack for Jakobstad in September

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

In September, Jakobstad sees daytime highs around 13°C and nights near 8°C. Worth packing: a warm layer and rain gear. About 11 days see rain.

a warm layerrain gear

Sea temperature near Jakobstad in September

The nearest coast averages about 13°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 17 km away) is warmest in August at about 16°C and coldest in February near 0°C.

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

0°5°10°15°20°JanFebMarAprMayJunJulAugSepOctNovDecbracingcool
Sea temperature (°C)Comfort
Jan1Bracing
Feb0Bracing
Mar0Bracing
Apr1Bracing
May3Bracing
Jun8Bracing
Jul14Bracing
Aug16Cool
Sep13Bracing
Oct9Bracing
Nov5Bracing
Dec3Bracing

UV index in Jakobstad 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 Jakobstad peaks around July 14 at about 4 (moderate) — 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.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateLowJul 14UV 4Jan 1UV 0
UV index (midday)Level
Jan0Low
Feb0Low
Mar1Low
Apr2Moderate
May4Moderate
Jun4Moderate
Jul4Moderate
Aug4Moderate
Sep2Low
Oct1Low
Nov0Low
Dec0Low
Location & terrain

Where is Jakobstad?

Jakobstad sits at 63.7°N, 22.7°E, 15 m above sea level, in Finland. The nearest listed city is Kokkola, 28 km away.

KauhavaKorsholmVaasaSeinäjokiYlivieskaKurikkaUmeå

Topography around Jakobstad

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

Within 3 km, the terrain around Jakobstad has only modest variations in elevation — a maximum elevation change of 26 m around an average of 9 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 56 m; within 80 km, only modest variations in elevation — a maximum elevation change of 181 m.

The land around Jakobstad is covered by trees (57%) within 3 km, trees (46%) and water (35%) within 16 km, and trees (48%) and water (38%) within 80 km.

3 km
26 m
16 km
56 m
80 km
181 m
treesgrasslandcroplandartificial surfaceswaterwetland
September weather nearby: Kokkola 28 km · Kauhava 66 km · Korsholm 80 km · Vaasa 84 km · Seinäjoki 98 km · Ylivieska 101 km · Kurikka 119 km · Umeå 121 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 Jakobstad (63.6749°, 22.7026°, elevation 15 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).