Imatra weather in September

In September, Imatra sees average daytime highs of 14°C and overnight lows near 8°C, with 55 mm of rain across 11.1 wet days and about 12.6 hours of daylight. It is the 5th-warmest and 5th-wettest month of the year here.

Highs ease over the month, from about 17°C in the first days to 11°C by the end. The sky is clear or mostly clear about 13% 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 Imatra's 7th-clearest and 7th-windiest month. For the whole year in context, see Imatra's year-round climate.

Daytime high
14°
5th warmest
Overnight low
9th coldest
Rainfall
55 mm
11.1 wet days
Daylight
12 h 36 min
5:42 AM – 6:16 PM
Cloud cover
72%
7th clearest
Wind
13 km/h
7th windiest
Solar energy
2.29 kWh/m²
Travel score
3.9
out of 10

Imatra is urban settlement in South Karelia, Finland.

Air quality
Excellent
PM10 9.8 µg/m³ · 2019
Density
435/km²
people per km²

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 11°C by the end.

A typical September day in Imatra reaches about 14°C in the afternoon and slips back to 8°C overnight — a 6°C spread between the day's warmth and the night's chill. On most days the high lands between 10°C and 18°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)
11710
21710
31710
41710
51610
6169
7169
8169
9169
10159
11159
12158
13158
14148
15148
16148
17147
18147
19137
20137
21137
22137
23137
24126
25126
26126
27126
28116
29116
30116

How September really feels in Imatra

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.

Imatra weather by month

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

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan-5° / -9°4110.9126.10.0
Feb-4° / -10°368.99.68.50.0
Mar / -6°358.98.411.30.0
Apr / -1°338.43.614.31.1
May14° / 4890.4174.3
Jun19° / 11°6612018.75.6
Jul21° / 13°7612.40186.1
Aug20° / 12°7312.1015.55.8
Sep14° / 5511.1012.63.9
Oct / 5611.21.79.60.9
Nov / -2°5211.36.56.90.0
Dec-2° / -6°5011.910.85.20.0

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 13% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 16% of September, with mostly cloudy or overcast conditions the remaining 70%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
13070
23169
33169
43169
53169
63268
73268
83268
93268
103268
113268
123169
133169
143070
153070
163070
173070
182971
192971
203070
213070
222872
232872
242971
252872
262872
272773
282773
292773
302773

Chance of precipitation in September

Any precipitation

Imatra gets around 55 mm of rain over 11.1 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 37% and peaks near 40% on the wettest days.

0%10%20%30%40%50%151015202530
Rain chance (%)
137
237
337
437
537
638
738
839
939
1040
1140
1240
1340
1439
1539
1639
1738
1837
1937
2036
2136
2235
2335
2435
2535
2634
2734
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 93% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)
179201
281181
382171
484160
586140
687130
788120
889110
990100
109190
119280
129370
139460
149460
159550
169640
179640
189730
199730
209730
219820
229820
239820
249910
259910
269910
279910
289910
2910000
3010000

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
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

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 5:04 AM to 6:18 AM, and sunset from 7:05 PM to 5:30 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
114.05:047:05
213.95:077:02
313.85:096:59
413.75:126:56
513.65:146:52
613.55:176:49
713.45:196:46
813.35:226:43
913.25:256:39
1013.15:276:36
1113.15:306:33
1213.05:326:29
1312.95:356:26
1412.85:376:23
1512.75:406:19
1612.65:426:16
1712.55:456:13
1812.45:486:10
1912.35:506:06
2012.25:536:03
2112.15:556:00
2212.05:585:56
2311.96:005:53
2411.86:035:50
2511.76:065:46
2611.66:085:43
2711.56:115:40
2811.46:135:37
2911.36:165:33
3011.26:185:30

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 2.29 kWh/m².

For context, solar energy here swings from a low near 0.11 kWh/m² to a high of 5.48 kWh/m² in June across the year — September's 2.29 kWh/m² falls in the middle.

01234151015202530
Solar energy (kWh/m²)Level
13.0Moderate
23.0Moderate
32.9Moderate
42.9Moderate
52.8Moderate
62.8Moderate
72.7Moderate
82.7Moderate
92.6Moderate
102.6Moderate
112.5Moderate
122.5Moderate
132.4Moderate
142.4Moderate
152.3Moderate
162.3Moderate
172.2Moderate
182.2Moderate
192.1Moderate
202.1Moderate
212.0Moderate
222.0Dim
231.9Dim
241.9Dim
251.8Dim
261.8Dim
271.7Dim
281.7Dim
291.6Dim
301.6Dim
Planning a trip in September

Is September a good time to visit Imatra?

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

3.9
Sightseeing
5th-best month of the year
0.3
Beach & pool
4th-best month of the year

September is a weaker month for outdoor sightseeing in Imatra.

What to pack for Imatra in September

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

In September, Imatra sees daytime highs around 14°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 Imatra 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 at the nearest coast (about 64 km away) is warmest in August at about 18°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°10°20°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshing
Sea temperature (°C)Comfort
Jan1Bracing
Feb0Bracing
Mar0Bracing
Apr1Bracing
May7Bracing
Jun13Bracing
Jul17Cool
Aug18Cool
Sep15Bracing
Oct10Bracing
Nov6Bracing
Dec3Bracing

UV index in Imatra 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 Imatra peaks around June 23 at about 5 (moderate) — 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.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateLowJun 23UV 5Dec 19UV 0
UV index (midday)Level
Jan0Low
Feb1Low
Mar2Low
Apr2Moderate
May4Moderate
Jun5Moderate
Jul5Moderate
Aug4Moderate
Sep2Moderate
Oct1Low
Nov0Low
Dec0Low
Location & terrain

Where is Imatra?

Imatra sits at 61.2°N, 28.8°E, 68 m above sea level, in Finland. The nearest listed city is Svetogorsk, 9.0 km away.

PriozërskSavonlinnaMikkeliHaminaKouvola

Topography around Imatra

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

Within 3 km, the terrain around Imatra has only modest variations in elevation — a maximum elevation change of 75 m around an average of 71 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 136 m; within 80 km, only modest variations in elevation — a maximum elevation change of 245 m.

The land around Imatra is covered by trees (65%) within 3 km, trees (62%) and water (24%) within 16 km, and trees (73%) and water (21%) within 80 km.

3 km
75 m
16 km
136 m
80 km
245 m
treesgrasslandcroplandartificial surfacesbare terrainwaterwetland
September weather nearby: Svetogorsk 9.0 km · Lappeenranta 33 km · Vyborg 52 km · Priozërsk 76 km · Savonlinna 78 km · Mikkeli 97 km · Hamina 108 km · Kouvola 116 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 Imatra (61.1718°, 28.7524°, elevation 68 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).