Pori weather in September

In September, Pori sees average daytime highs of 14°C and overnight lows near 9°C, with 62 mm of rain across 10.2 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 16°C in the first days to 12°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 hours at the start of September to 11 h 12 min by month's end. Set against the rest of the year, September is Pori's 6th-clearest and 7th-windiest month. For the whole year in context, see Pori's year-round climate.

Daytime high: 14°; 4th warmest
Overnight low: 9°; 9th coldest
Rainfall: 62 mm; 10.2 wet days
Daylight: 12 h 36 min; 6:10 AM – 6:44 PM
Cloud cover: 65%; 6th clearest
Wind: 16 km/h; 7th windiest
Solar energy: 2.53 kWh/m²
Travel score: 4.1; out of 10

Air quality: Excellent; PM10 12.2 µg/m³ · 2019

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

← August Pori year-round climate October →Best places to visit in September

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 16°C in the first days to 12°C by the end.

A typical September day in Pori reaches about 14°C in the afternoon and slips back to 9°C overnight — a 5°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.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Avg high (°C)	17	17	16	16	16	16	16	16	15	15	15	15	15	14	14	14	14	14	14	13	13	13	13	13	12	12	12	12	12	12
Avg low (°C)	11	11	11	11	10	10	10	10	10	10	10	9	9	9	9	9	9	8	8	8	8	8	8	8	7	7	7	7	7	7

	Avg high (°C)	Avg low (°C)
1	17	11
2	17	11
3	16	11
4	16	11
5	16	10
6	16	10
7	16	10
8	16	10
9	15	10
10	15	10
11	15	10
12	15	9
13	15	9
14	14	9
15	14	9
16	14	9
17	14	9
18	14	8
19	14	8
20	13	8
21	13	8
22	13	8
23	13	8
24	13	8
25	12	7
26	12	7
27	12	7
28	12	7
29	12	7
30	12	7

How September really feels in Pori

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

heat index over the day's high

Days feeling ≤ 0°C

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.

Pori 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.

Month	High / Low (°C)	Rainfall (mm)	Wet days	Snow days	Daylight (hours)	Travel score
Jan	-1° / -5°	43	10.2	8.5	6	0.0
Feb	-2° / -6°	34	8	7.6	8.4	0.0
Mar	2° / -4°	33	8.3	6	11.3	0.0
Apr	7° / 1°	33	8.2	2	14.3	0.8
May	12° / 5°	39	7.8	0.2	17.1	3.3
Jun	16° / 10°	60	10.3	0	18.9	5.0
Jul	20° / 13°	74	11.7	0	18.1	6.0
Aug	19° / 13°	74	12.2	0	15.6	5.7
Sep	14° / 9°	62	10.2	0	12.6	4.1
Oct	8° / 4°	65	11.5	0.9	9.6	1.3
Nov	4° / 1°	56	11.1	3.7	6.8	0.0
Dec	1° / -3°	53	11.5	6.8	5.1	0.0

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 18% of September, with mostly cloudy or overcast conditions the remaining 62%.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Clearer (%)	38	38	38	38	38	40	40	40	40	40	40	40	40	39	40	40	40	40	39	39	39	38	37	37	37	36	35	35	35	34
Cloudier (%)	62	62	62	62	62	60	60	60	60	60	60	60	60	61	60	60	60	60	61	61	61	62	63	63	63	64	65	65	65	66

	Clearer (%)	Cloudier (%)
1	38	62
2	38	62
3	38	62
4	38	62
5	38	62
6	40	60
7	40	60
8	40	60
9	40	60
10	40	60
11	40	60
12	40	60
13	40	60
14	39	61
15	40	60
16	40	60
17	40	60
18	40	60
19	39	61
20	39	61
21	39	61
22	38	62
23	37	63
24	37	63
25	37	63
26	36	64
27	35	65
28	35	65
29	35	65
30	34	66

Chance of precipitation in September

Any precipitation

Pori gets around 62 mm of rain over 10.2 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 41% on the wettest days. The odds ease toward the end of the month.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Rain chance (%)	41	41	40	40	39	39	38	38	37	36	36	35	34	34	33	32	32	31	31	31	30	30	30	31	31	31	32	33	34	35

	Rain chance (%)
1	41
2	41
3	40
4	40
5	39
6	39
7	38
8	38
9	37
10	36
11	36
12	35
13	34
14	34
15	33
16	32
17	32
18	31
19	31
20	31
21	30
22	30
23	30
24	31
25	31
26	31
27	32
28	33
29	34
30	35

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 91% of days. It rarely turns muggy — the humid and sticky bands barely register.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Dry (%)	76	78	79	80	81	83	84	85	86	87	89	90	91	92	93	94	95	96	96	97	97	98	98	98	98	98	99	99	99	99
Comfortable (%)	22	21	20	19	18	17	16	15	14	13	11	10	9	8	7	6	5	4	4	3	3	2	2	2	2	2	1	1	1	1
Humid (%)	2	1	1	1	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0

	Dry (%)	Comfortable (%)	Humid (%)
1	76	22	2
2	78	21	1
3	79	20	1
4	80	19	1
5	81	18	1
6	83	17	0
7	84	16	0
8	85	15	0
9	86	14	0
10	87	13	0
11	89	11	0
12	90	10	0
13	91	9	0
14	92	8	0
15	93	7	0
16	94	6	0
17	95	5	0
18	96	4	0
19	96	4	0
20	97	3	0
21	97	3	0
22	98	2	0
23	98	2	0
24	98	2	0
25	98	2	0
26	98	2	0
27	99	1	0
28	99	1	0
29	99	1	0
30	99	1	0

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.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Wind speed (km/h)	15	15	15	15	15	15	16	16	16	16	16	16	16	16	16	16	16	16	16	16	16	16	16	16	16	16	16	17	17	17
Feels	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze

	Wind speed (km/h)	Feels
1	15	light breeze
2	15	light breeze
3	15	light breeze
4	15	light breeze
5	15	light breeze
6	15	light breeze
7	16	light breeze
8	16	light breeze
9	16	light breeze
10	16	light breeze
11	16	light breeze
12	16	light breeze
13	16	light breeze
14	16	light breeze
15	16	light breeze
16	16	light breeze
17	16	light breeze
18	16	light breeze
19	16	light breeze
20	16	light breeze
21	16	light breeze
22	16	light breeze
23	16	light breeze
24	16	light breeze
25	16	light breeze
26	16	light breeze
27	16	light breeze
28	17	light breeze
29	17	light breeze
30	17	light 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 5:31 AM to 6:47 AM, and sunset from 7:34 PM to 5:58 PM.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Daylight (h)	14.0	14.0	13.9	13.8	13.7	13.6	13.5	13.4	13.3	13.2	13.1	13.0	12.9	12.8	12.7	12.6	12.5	12.4	12.3	12.2	12.1	12.0	11.9	11.8	11.7	11.6	11.5	11.4	11.3	11.2
Sunrise (AM)	5:31	5:34	5:36	5:39	5:42	5:44	5:47	5:49	5:52	5:55	5:57	6:00	6:02	6:05	6:08	6:10	6:13	6:15	6:18	6:20	6:23	6:26	6:28	6:31	6:34	6:36	6:39	6:41	6:44	6:47
Sunset (PM)	7:34	7:31	7:27	7:24	7:21	7:18	7:14	7:11	7:08	7:04	7:01	6:58	6:54	6:51	6:48	6:44	6:41	6:38	6:34	6:31	6:28	6:24	6:21	6:18	6:14	6:11	6:08	6:04	6:01	5:58

	Daylight (h)	Sunrise (AM)	Sunset (PM)
1	14.0	5:31	7:34
2	14.0	5:34	7:31
3	13.9	5:36	7:27
4	13.8	5:39	7:24
5	13.7	5:42	7:21
6	13.6	5:44	7:18
7	13.5	5:47	7:14
8	13.4	5:49	7:11
9	13.3	5:52	7:08
10	13.2	5:55	7:04
11	13.1	5:57	7:01
12	13.0	6:00	6:58
13	12.9	6:02	6:54
14	12.8	6:05	6:51
15	12.7	6:08	6:48
16	12.6	6:10	6:44
17	12.5	6:13	6:41
18	12.4	6:15	6:38
19	12.3	6:18	6:34
20	12.2	6:20	6:31
21	12.1	6:23	6:28
22	12.0	6:26	6:24
23	11.9	6:28	6:21
24	11.8	6:31	6:18
25	11.7	6:34	6:14
26	11.6	6:36	6:11
27	11.5	6:39	6:08
28	11.4	6:41	6:04
29	11.3	6:44	6:01
30	11.2	6:47	5:58

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 2.53 kWh/m².

For context, solar energy here swings from a low near 0.12 kWh/m² to a high of 5.97 kWh/m² in June across the year — September's 2.53 kWh/m² falls in the middle.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Solar energy (kWh/m²)	3.3	3.2	3.2	3.1	3.1	3.0	3.0	2.9	2.9	2.8	2.8	2.7	2.6	2.6	2.5	2.5	2.5	2.4	2.4	2.3	2.2	2.2	2.1	2.1	2.0	2.0	1.9	1.9	1.8	1.8
Level	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Dim	Dim	Dim	Dim	Dim

	Solar energy (kWh/m²)	Level
1	3.3	Moderate
2	3.2	Moderate
3	3.2	Moderate
4	3.1	Moderate
5	3.1	Moderate
6	3.0	Moderate
7	3.0	Moderate
8	2.9	Moderate
9	2.9	Moderate
10	2.8	Moderate
11	2.8	Moderate
12	2.7	Moderate
13	2.6	Moderate
14	2.6	Moderate
15	2.5	Moderate
16	2.5	Moderate
17	2.5	Moderate
18	2.4	Moderate
19	2.4	Moderate
20	2.3	Moderate
21	2.2	Moderate
22	2.2	Moderate
23	2.1	Moderate
24	2.1	Moderate
25	2.0	Moderate
26	2.0	Dim
27	1.9	Dim
28	1.9	Dim
29	1.8	Dim
30	1.8	Dim

Planning a trip in September

Is September a good time to visit Pori?

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

4.1

Sightseeing

4th-best month of the year

0.2

Beach & pool

4th-best month of the year

September is a reasonable time to visit Pori for sightseeing.

What to pack for Pori in September

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

In September, Pori sees daytime highs around 14°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 Pori 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 25 km away) 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.

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Sea temperature (°C)	2	1	1	2	5	10	15	17	14	10	7	4
Comfort	Bracing	Bracing	Bracing	Bracing	Bracing	Bracing	Cool	Cool	Bracing	Bracing	Bracing	Bracing

	Sea temperature (°C)	Comfort
Jan	2	Bracing
Feb	1	Bracing
Mar	1	Bracing
Apr	2	Bracing
May	5	Bracing
Jun	10	Bracing
Jul	15	Cool
Aug	17	Cool
Sep	14	Bracing
Oct	10	Bracing
Nov	7	Bracing
Dec	4	Bracing

UV index in Pori 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 Pori peaks around June 16 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.

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
UV index (midday)	0	1	1	2	4	5	4	4	2	1	0	0
Level	Low	Low	Low	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Low	Low	Low

	UV index (midday)	Level
Jan	0	Low
Feb	1	Low
Mar	1	Low
Apr	2	Moderate
May	4	Moderate
Jun	5	Moderate
Jul	4	Moderate
Aug	4	Moderate
Sep	2	Moderate
Oct	1	Low
Nov	0	Low
Dec	0	Low

Location & terrain

Where is Pori?

Pori sits at 61.5°N, 21.8°E, 20 m above sea level, in Finland. The nearest listed city is Rauma, 42 km away.

Topography around Pori

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

Within 3 km, the terrain around Pori has only modest variations in elevation — a maximum elevation change of 35 m around an average of 8 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 74 m; within 80 km, significant variations in elevation — a maximum elevation change of 253 m.

The land around Pori is covered by trees (39%) and artificial surfaces (33%) within 3 km, trees (62%) within 16 km, and trees (61%) and water (25%) within 80 km.

3 km

35 m

trees 39%

16 km

74 m

trees 62%

80 km

253 m

trees 61%

treesgrasslandcroplandartificial surfaceswaterwetland

← August Pori year-round climate October →Best places to visit in September

September weather nearby: Rauma 42 km · Vammala 62 km · Sastamala 62 km · Nokia 91 km · Ylöjärvi 96 km · Loimaa 98 km · Pirkkala 98 km · Lempäälä 106 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

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 Pori (61.4807°, 21.7852°, elevation 20 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).

	Avg high (°C)	Avg low (°C)
1	17	11
2	17	11
3	16	11
4	16	11
5	16	10
6	16	10
7	16	10
8	16	10
9	15	10
10	15	10
11	15	10
12	15	9
13	15	9
14	14	9
15	14	9
16	14	9
17	14	9
18	14	8
19	14	8
20	13	8
21	13	8
22	13	8
23	13	8
24	13	8
25	12	7
26	12	7
27	12	7
28	12	7
29	12	7
30	12	7

	Clearer (%)	Cloudier (%)
1	38	62
2	38	62
3	38	62
4	38	62
5	38	62
6	40	60
7	40	60
8	40	60
9	40	60
10	40	60
11	40	60
12	40	60
13	40	60
14	39	61
15	40	60
16	40	60
17	40	60
18	40	60
19	39	61
20	39	61
21	39	61
22	38	62
23	37	63
24	37	63
25	37	63
26	36	64
27	35	65
28	35	65
29	35	65
30	34	66

	Rain chance (%)
1	41
2	41
3	40
4	40
5	39
6	39
7	38
8	38
9	37
10	36
11	36
12	35
13	34
14	34
15	33
16	32
17	32
18	31
19	31
20	31
21	30
22	30
23	30
24	31
25	31
26	31
27	32
28	33
29	34
30	35

	Dry (%)	Comfortable (%)	Humid (%)
1	76	22	2
2	78	21	1
3	79	20	1
4	80	19	1
5	81	18	1
6	83	17	0
7	84	16	0
8	85	15	0
9	86	14	0
10	87	13	0
11	89	11	0
12	90	10	0
13	91	9	0
14	92	8	0
15	93	7	0
16	94	6	0
17	95	5	0
18	96	4	0
19	96	4	0
20	97	3	0
21	97	3	0
22	98	2	0
23	98	2	0
24	98	2	0
25	98	2	0
26	98	2	0
27	99	1	0
28	99	1	0
29	99	1	0
30	99	1	0

	Avg high (°C)	Avg low (°C)
1	17	11
2	17	11
3	16	11
4	16	11
5	16	10
6	16	10
7	16	10
8	16	10
9	15	10
10	15	10
11	15	10
12	15	9
13	15	9
14	14	9
15	14	9
16	14	9
17	14	9
18	14	8
19	14	8
20	13	8
21	13	8
22	13	8
23	13	8
24	13	8
25	12	7
26	12	7
27	12	7
28	12	7
29	12	7
30	12	7

	Clearer (%)	Cloudier (%)
1	38	62
2	38	62
3	38	62
4	38	62
5	38	62
6	40	60
7	40	60
8	40	60
9	40	60
10	40	60
11	40	60
12	40	60
13	40	60
14	39	61
15	40	60
16	40	60
17	40	60
18	40	60
19	39	61
20	39	61
21	39	61
22	38	62
23	37	63
24	37	63
25	37	63
26	36	64
27	35	65
28	35	65
29	35	65
30	34	66

	Rain chance (%)
1	41
2	41
3	40
4	40
5	39
6	39
7	38
8	38
9	37
10	36
11	36
12	35
13	34
14	34
15	33
16	32
17	32
18	31
19	31
20	31
21	30
22	30
23	30
24	31
25	31
26	31
27	32
28	33
29	34
30	35

	Dry (%)	Comfortable (%)	Humid (%)
1	76	22	2
2	78	21	1
3	79	20	1
4	80	19	1
5	81	18	1
6	83	17	0
7	84	16	0
8	85	15	0
9	86	14	0
10	87	13	0
11	89	11	0
12	90	10	0
13	91	9	0
14	92	8	0
15	93	7	0
16	94	6	0
17	95	5	0
18	96	4	0
19	96	4	0
20	97	3	0
21	97	3	0
22	98	2	0
23	98	2	0
24	98	2	0
25	98	2	0
26	98	2	0
27	99	1	0
28	99	1	0
29	99	1	0
30	99	1	0

	Avg high (°C)	Avg low (°C)
1	17	11
2	17	11
3	16	11
4	16	11
5	16	10
6	16	10
7	16	10
8	16	10
9	15	10
10	15	10
11	15	10
12	15	9
13	15	9
14	14	9
15	14	9
16	14	9
17	14	9
18	14	8
19	14	8
20	13	8
21	13	8
22	13	8
23	13	8
24	13	8
25	12	7
26	12	7
27	12	7
28	12	7
29	12	7
30	12	7

	Clearer (%)	Cloudier (%)
1	38	62
2	38	62
3	38	62
4	38	62
5	38	62
6	40	60
7	40	60
8	40	60
9	40	60
10	40	60
11	40	60
12	40	60
13	40	60
14	39	61
15	40	60
16	40	60
17	40	60
18	40	60
19	39	61
20	39	61
21	39	61
22	38	62
23	37	63
24	37	63
25	37	63
26	36	64
27	35	65
28	35	65
29	35	65
30	34	66

	Rain chance (%)
1	41
2	41
3	40
4	40
5	39
6	39
7	38
8	38
9	37
10	36
11	36
12	35
13	34
14	34
15	33
16	32
17	32
18	31
19	31
20	31
21	30
22	30
23	30
24	31
25	31
26	31
27	32
28	33
29	34
30	35

	Dry (%)	Comfortable (%)	Humid (%)
1	76	22	2
2	78	21	1
3	79	20	1
4	80	19	1
5	81	18	1
6	83	17	0
7	84	16	0
8	85	15	0
9	86	14	0
10	87	13	0
11	89	11	0
12	90	10	0
13	91	9	0
14	92	8	0
15	93	7	0
16	94	6	0
17	95	5	0
18	96	4	0
19	96	4	0
20	97	3	0
21	97	3	0
22	98	2	0
23	98	2	0
24	98	2	0
25	98	2	0
26	98	2	0
27	99	1	0
28	99	1	0
29	99	1	0
30	99	1	0