Joensuu weather in September

In September, Joensuu sees average daytime highs of 13°C and overnight lows near 8°C, with 68 mm of precipitation across 11.9 wet days and about 12.6 hours of daylight. It is the 4th-warmest and 4th-wettest month of the year here.

Highs ease over the month, from about 15°C in the first days to 10°C by the end. The sky is clear or mostly clear about 11% of the time in September, and the air most often feels dry.

Daylight stretches from about 14 h 12 min at the start of September to 11 h 06 min by month's end. Set against the rest of the year, September is Joensuu's 7th-clearest and 7th-windiest month. For the whole year in context, see Joensuu's year-round climate.

Daytime high
13°
4th warmest
Overnight low
9th coldest
Precipitation
68 mm
11.9 wet days
Daylight
12 h 36 min
5:37 AM – 6:13 PM
Cloud cover
75%
7th clearest
Wind
13 km/h
7th windiest
Solar energy
1.97 kWh/m²
Travel score
3.2
out of 10
Air quality
Excellent
PM10 8.7 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 10°C by the end.

A typical September day in Joensuu 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 8°C and 17°C. Set against its neighbours, September runs about 6°C cooler than August and about 7°C warmer than October.

10°15°20°25°151015202530
Avg high (°C)Avg low (°C)
11610
21610
31510
41510
51510
6159
7159
8149
9149
10149
11149
12148
13138
14138
15138
16138
17127
18127
19127
20127
21127
22117
23116
24116
25116
26116
27106
28106
29106
30105

How September really feels in Joensuu

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.

Joensuu weather by month

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

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan-6° / -10°4110.712.25.60.0
Feb-6° / -11°359.410.38.20.0
Mar-1° / -7°3499.611.20.0
Apr / -2°327.94.414.40.4
May12° / 499.30.617.43.3
Jun18° / 11°7512.7019.35.2
Jul20° / 14°8512.8018.55.9
Aug18° / 12°8213.2015.85.3
Sep13° / 6811.90.112.63.2
Oct / 6312.42.79.50.5
Nov / -3°5511.68.66.50.0
Dec-3° / -7°5312.712.54.60.0

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 11% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 14% of September, with mostly cloudy or overcast conditions the remaining 75%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
12872
22872
32872
42872
52872
62872
72872
82872
92872
102872
112872
122773
132773
142674
152674
162674
172575
182575
192575
202575
212476
222476
232377
242377
252377
262278
272278
282278
292179
302179

Chance of precipitation in September

Any precipitation

Joensuu gets around 68 mm of rain and snow over 11.9 wet days in September. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable precipitation averages around 40% and peaks near 41% on the wettest days, and about 0 day brings snow.

0%10%20%30%40%50%151015202530
Rain chance (%)
141
241
341
441
541
640
740
840
940
1040
1140
1240
1340
1440
1540
1640
1740
1840
1940
2040
2140
2240
2340
2440
2540
2640
2740
2840
2940
3040

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 94% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)
18218
28317
38416
48515
58614
68713
78812
88911
9919
10928
11937
12946
13955
14964
15973
16973
17982
18982
19991
20991
21991
22991
231000
241000
251000
261000
271000
281000
291000
301000

Wind in September

Winds average 13 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.

05101520151015202530
Wind speed (km/h)Feels
112calm
212calm
312calm
412light breeze
512light breeze
612light breeze
712light breeze
812light breeze
912light breeze
1012light breeze
1112light breeze
1212light 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

Sunrise & sunset in September

DaylightNight

Daylight runs from about 14 h 12 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 186 minutes over September. Sunrise moves from 4:56 AM to 6:16 AM, and sunset from 7:05 PM to 5:25 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
114.24:567:05
214.04:597:02
313.95:026:58
413.85:046:55
513.75:076:51
613.65:106:48
713.55:136:44
813.45:156:41
913.35:186:38
1013.25:216:34
1113.15:246:31
1213.05:266:27
1312.95:296:24
1412.85:326:20
1512.75:356:17
1612.65:376:13
1712.55:406:10
1812.45:436:06
1912.35:466:03
2012.25:485:59
2112.15:515:56
2212.05:545:52
2311.95:575:49
2411.85:595:45
2511.76:025:42
2611.66:055:38
2711.56:085:35
2811.46:105:31
2911.26:135:28
3011.16:165:25

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 1.97 kWh/m².

For context, solar energy here swings from a low near 0.08 kWh/m² to a high of 5.31 kWh/m² in June across the year — September's 1.97 kWh/m² falls in the middle.

0123151015202530
Solar energy (kWh/m²)Level
12.7Moderate
22.7Moderate
32.6Moderate
42.5Moderate
52.5Moderate
62.4Moderate
72.4Moderate
82.3Moderate
92.3Moderate
102.2Moderate
112.2Moderate
122.1Moderate
132.1Moderate
142.0Moderate
152.0Dim
161.9Dim
171.9Dim
181.8Dim
191.8Dim
201.8Dim
211.7Dim
221.7Dim
231.6Dim
241.6Dim
251.5Dim
261.5Dim
271.4Dim
281.4Dim
291.4Dim
301.3Dim
Planning a trip in September

Is September a good time to visit Joensuu?

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

3.2
Sightseeing
5th-best month of the year
0.1
Beach & pool
4th-best month of the year

September is a weaker month for outdoor sightseeing in Joensuu.

What to pack for Joensuu in September

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

In September, Joensuu sees daytime highs around 13°C and nights near 8°C. Worth packing: a warm layer and rain gear. About 12 days see rain.

a warm layerrain gear

UV index in Joensuu 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 Joensuu peaks around July 14 at about 5 (moderate) — a little sun protection helps at midday. It bottoms out near December 17 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 5Dec 17UV 0
UV index (midday)Level
Jan0Low
Feb1Low
Mar1Low
Apr3Moderate
May4Moderate
Jun4Moderate
Jul5Moderate
Aug4Moderate
Sep2Low
Oct1Low
Nov0Low
Dec0Low
Location & terrain

Where is Joensuu?

Joensuu sits at 62.6°N, 29.8°E, 72 m above sea level, in Finland. The nearest listed city is Kontiolahti, 18 km away.

SavonlinnaVarkausSortavalaKuopioSiilinjärviPieksämäkiMikkeli

Topography around Joensuu

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

Within 3 km, the terrain around Joensuu has only modest variations in elevation — a maximum elevation change of 43 m around an average of 83 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 112 m; within 80 km, significant variations in elevation — a maximum elevation change of 317 m.

The land around Joensuu is covered by trees (44%) and artificial surfaces (32%) within 3 km, trees (54%) and water (30%) within 16 km, and trees (74%) and water (21%) within 80 km.

3 km
43 m
16 km
112 m
80 km
317 m
treesgrasslandcroplandartificial surfaceswaterwetland
September weather nearby: Kontiolahti 18 km · Savonlinna 93 km · Varkaus 102 km · Sortavala 110 km · Kuopio 111 km · Siilinjärvi 119 km · Pieksämäki 139 km · Mikkeli 164 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 Joensuu (62.6012°, 29.7632°, elevation 72 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. 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).