Hamina weather in September

In September, Hamina sees average daytime highs of 15°C and overnight lows near 9°C, with 59 mm of rain across 10.3 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 12°C by the end. The sky is clear or mostly clear about 18% 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 Hamina's 6th-clearest and 6th-windiest month. For the whole year in context, see Hamina's year-round climate.

Daytime high
15°
4th warmest
Overnight low
9th coldest
Rainfall
59 mm
10.3 wet days
Daylight
12 h 30 min
5:49 AM – 6:22 PM
Cloud cover
69%
6th clearest
Wind
15 km/h
6th windiest
Solar energy
2.44 kWh/m²
Travel score
4.2
out of 10

Hamina is urban area in Hamina, Finland.

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 12°C by the end.

A typical September day in Hamina 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 7°C warmer than October.

10°15°20°25°151015202530
Avg high (°C)Avg low (°C)
11811
21711
31711
41710
51710
61710
71610
81610
91610
10169
11169
12159
13159
14159
15159
16158
17148
18148
19148
20148
21148
22137
23137
24137
25137
26137
27127
28127
29127
30126

How September really feels in Hamina

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.

Hamina 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-3° / -7°4811.1116.20.0
Feb-3° / -8°429.39.48.60.0
Mar / -5°389.27.311.30.0
Apr / -0°368.82.514.21.0
May14° / 449.40.116.94.0
Jun18° / 10°6510.7018.55.5
Jul21° / 14°5910.7017.86.4
Aug20° / 13°6811.5015.46.0
Sep15° / 5910.3012.64.2
Oct / 6511.81.19.71.3
Nov / -0°6112.15.170.0
Dec-0° / -4°6012.19.25.50.0

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 18% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 15% of September, with mostly cloudy or overcast conditions the remaining 67%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
13070
23070
33169
43268
53268
63367
73367
83466
93466
103466
113466
123565
133565
143664
153664
163565
173664
183565
193664
203565
213466
223367
233367
243367
253268
263268
273268
283169
293070
303070

Chance of precipitation in September

Any precipitation

Hamina gets around 59 mm of rain over 10.3 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 (%)
136
235
335
435
535
635
735
836
936
1036
1136
1236
1336
1436
1536
1635
1735
1835
1934
2034
2134
2233
2333
2433
2533
2633
2733
2833
2933
3034

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 (%)
173243
276222
377212
478202
579192
681172
783161
884151
985141
1086131
1188111
1289101
139190
149280
159280
169370
179460
189550
199640
209640
219730
229820
239820
249820
259910
269910
279910
289910
2910000
3010000

Wind in September

Winds average 15 km/h in September.

Across September, daily wind ranges from about 14 km/h on the calmest days to 16 km/h at its breeziest. It stays fairly steady from day to day.

05101520151015202530
Wind speed (km/h)Feels
114light breeze
214light breeze
314light breeze
414light breeze
514light breeze
614light breeze
714light breeze
814light breeze
914light breeze
1014light breeze
1115light breeze
1215light breeze
1315light breeze
1415light breeze
1515light breeze
1615light breeze
1715light breeze
1815light breeze
1915light breeze
2015light breeze
2115light breeze
2215light breeze
2315light breeze
2415light breeze
2515light breeze
2615light breeze
2715light breeze
2815light breeze
2916light breeze
3016light 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 5:12 AM to 6:24 AM, and sunset from 7:10 PM to 5:37 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
114.05:127:10
213.95:147:07
313.85:177:04
413.75:197:01
513.65:226:57
613.55:246:54
713.45:276:51
813.35:296:48
913.25:326:45
1013.15:346:41
1113.05:376:38
1212.95:396:35
1312.85:426:32
1412.75:446:28
1512.65:476:25
1612.55:496:22
1712.55:526:19
1812.45:546:16
1912.35:576:12
2012.25:596:09
2112.16:026:06
2212.06:046:03
2311.96:075:59
2411.86:095:56
2511.76:125:53
2611.66:145:50
2711.56:175:47
2811.46:195:43
2911.36:225:40
3011.26:245:37

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 2.44 kWh/m².

For context, solar energy here swings from a low near 0.15 kWh/m² to a high of 5.62 kWh/m² in June across the year — September's 2.44 kWh/m² falls in the middle.

01234151015202530
Solar energy (kWh/m²)Level
13.2Moderate
23.1Moderate
33.1Moderate
43.0Moderate
53.0Moderate
62.9Moderate
72.9Moderate
82.8Moderate
92.8Moderate
102.7Moderate
112.7Moderate
122.6Moderate
132.6Moderate
142.5Moderate
152.5Moderate
162.4Moderate
172.4Moderate
182.3Moderate
192.3Moderate
202.2Moderate
212.2Moderate
222.1Moderate
232.1Moderate
242.0Moderate
252.0Dim
261.9Dim
271.9Dim
281.8Dim
291.8Dim
301.7Dim
Planning a trip in September

Is September a good time to visit Hamina?

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

4.2
Sightseeing
4th-best month of the year
0.4
Beach & pool
4th-best month of the year

September is a reasonable time to visit Hamina for sightseeing.

What to pack for Hamina in September

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

In September, Hamina 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 Hamina 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 22 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
Apr2Bracing
May6Bracing
Jun12Bracing
Jul17Cool
Aug18Cool
Sep14Bracing
Oct10Bracing
Nov7Bracing
Dec4Bracing

UV index in Hamina 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 Hamina peaks around June 21 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.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighModerateLowJun 21UV 5Dec 19UV 0
UV index (midday)Level
Jan0Low
Feb1Low
Mar2Low
Apr3Moderate
May4Moderate
Jun5High
Jul5Moderate
Aug4Moderate
Sep2Moderate
Oct1Low
Nov0Low
Dec0Low
Location & terrain

Where is Hamina?

Hamina sits at 60.6°N, 27.2°E, 3 m above sea level, in Finland. The nearest listed city is Karhula, 16 km away.

LappeenrantaOrimattilaVyborgPorvoo

Topography around Hamina

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

Within 3 km, the terrain around Hamina has only modest variations in elevation — a maximum elevation change of 40 m around an average of 9 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 98 m; within 80 km, only modest variations in elevation — a maximum elevation change of 230 m.

The land around Hamina is covered by trees (49%) within 3 km, trees (56%) and water (27%) within 16 km, and water (46%) and trees (45%) within 80 km.

3 km
40 m
16 km
98 m
80 km
230 m
treesgrasslandcroplandartificial surfacesbare terrainwaterwetland
September weather nearby: Karhula 16 km · Kotka 18 km · Anjala 24 km · Kouvola 43 km · Lappeenranta 76 km · Orimattila 84 km · Vyborg 86 km · Porvoo 86 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 Hamina (60.5697°, 27.1979°, elevation 3 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).