Hafnarfjörður weather in September

In September, Hafnarfjörður sees average daytime highs of 11°C and overnight lows near 6°C, with 134 mm of precipitation across 17.6 wet days and about 12.7 hours of daylight. It is the 4th-warmest and 1st-wettest month of the year here.

Highs ease over the month, from about 12°C in the first days to 9°C by the end. The sky is clear or mostly clear about 9% 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 Hafnarfjörður's 8th-clearest and 7th-windiest month. For the whole year in context, see Hafnarfjörður's year-round climate.

Daytime high: 11°; 4th warmest
Overnight low: 6°; 9th coldest
Precipitation: 134 mm; 17.6 wet days
Daylight: 12 h 36 min; 7:03 AM – 7:41 PM
Cloud cover: 79%; 8th clearest
Wind: 16 km/h; 7th windiest
Solar energy: 2.04 kWh/m²
Travel score: 2.0; out of 10

Hafnarfjörður is town of Iceland.

Air quality: Excellent; PM2.5 4.5 µg/m³ · 2019
Density: 181/km²; people per km²

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

← August Hafnarfjörður 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 12°C in the first days to 9°C by the end.

A typical September day in Hafnarfjörður reaches about 11°C in the afternoon and slips back to 6°C overnight — a 4°C spread between the day's warmth and the night's chill. On most days the high lands between 8°C and 13°C. Set against its neighbours, September runs about 3°C cooler than August and about 4°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)	12	12	12	12	12	12	12	12	11	11	11	11	11	11	11	11	11	10	10	10	10	10	10	10	10	9	9	9	9	9
Avg low (°C)	8	8	8	8	7	7	7	7	7	7	7	7	7	6	6	6	6	6	6	6	6	6	6	5	5	5	5	5	5	5

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

How September really feels in Hafnarfjörður

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.

Hafnarfjörður weather by month

How September compares with the rest of the year at a glance. September is the 4th-warmest and 1st-wettest month here — the current month is highlighted below.

Month	High / Low (°C)	Rainfall (mm)	Wet days	Snow days	Daylight (hours)	Travel score
Jan	2° / -2°	128	17.8	11.6	5	0.0
Feb	3° / -2°	126	16.9	12.1	7.9	0.0
Mar	3° / -2°	118	17.2	11.4	11.2	0.0
Apr	6° / 1°	101	16.5	5.6	14.6	0.5
May	10° / 4°	90	15.8	0.7	17.9	1.7
Jun	12° / 7°	79	14.2	0.1	20.1	2.8
Jul	14° / 9°	85	14.5	0	19.2	3.5
Aug	13° / 9°	104	15.8	0	16.1	3.2
Sep	11° / 6°	134	17.6	0.2	12.7	2.0
Oct	7° / 3°	116	14.9	2.3	9.3	0.7
Nov	4° / 0°	117	16.3	6.6	6	0.0
Dec	3° / -2°	129	17.5	11	3.9	0.0

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 9% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 12% of September, with mostly cloudy or overcast conditions the remaining 79%.

	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 (%)	15	15	16	17	17	18	18	18	19	20	20	21	21	22	22	22	22	22	22	23	23	23	23	23	23	23	24	24	24	24
Cloudier (%)	85	85	84	83	83	82	82	82	81	80	80	79	79	78	78	78	78	78	78	77	77	77	77	77	77	77	76	76	76	76

	Clearer (%)	Cloudier (%)
1	15	85
2	15	85
3	16	84
4	17	83
5	17	83
6	18	82
7	18	82
8	18	82
9	19	81
10	20	80
11	20	80
12	21	79
13	21	79
14	22	78
15	22	78
16	22	78
17	22	78
18	22	78
19	22	78
20	23	77
21	23	77
22	23	77
23	23	77
24	23	77
25	23	77
26	23	77
27	24	76
28	24	76
29	24	76
30	24	76

Chance of precipitation in September

Any precipitationSnow

Hafnarfjörður gets around 134 mm of rain and snow over 17.6 wet days in September, the wettest month. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable precipitation averages around 58% and peaks near 59% on the wettest days, and about 0 day brings snow.

	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 (%)	57	58	58	58	58	58	58	58	58	57	57	57	57	57	57	57	58	58	58	58	58	59	59	59	59	59	59	59	59	58
Snow chance (%)	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	1	1	1	1	1	1	1	2	2	2	3	3	3	4

	Rain chance (%)	Snow chance (%)
1	57	0
2	58	0
3	58	0
4	58	0
5	58	0
6	58	0
7	58	0
8	58	0
9	58	0
10	57	0
11	57	0
12	57	0
13	57	0
14	57	0
15	57	0
16	57	0
17	58	1
18	58	1
19	58	1
20	58	1
21	58	1
22	59	1
23	59	1
24	59	2
25	59	2
26	59	2
27	59	3
28	59	3
29	59	3
30	58	4

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 100% 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 (%)	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100

	Dry (%)
1	100
2	100
3	100
4	100
5	100
6	100
7	100
8	100
9	100
10	100
11	100
12	100
13	100
14	100
15	100
16	100
17	100
18	100
19	100
20	100
21	100
22	100
23	100
24	100
25	100
26	100
27	100
28	100
29	100
30	100

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 16 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	15	16	16	16	16	16	16	16	16	16	16	16	16	16	16	16	16	16	16	16	16	16	16	16
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	15	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	16	light breeze
29	16	light breeze
30	16	light 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 6:19 AM to 7:44 AM, and sunset from 8:36 PM to 6:50 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)	14.3	14.2	14.1	14.0	13.9	13.7	13.6	13.5	13.4	13.3	13.2	13.1	13.0	12.9	12.7	12.6	12.5	12.4	12.3	12.2	12.1	12.0	11.9	11.8	11.6	11.5	11.4	11.3	11.2	11.1
Sunrise (AM)	6:19	6:22	6:25	6:27	6:30	6:33	6:36	6:39	6:42	6:45	6:48	6:51	6:54	6:57	7:00	7:03	7:06	7:09	7:12	7:15	7:18	7:21	7:24	7:27	7:30	7:33	7:36	7:38	7:41	7:44
Sunset (PM)	8:36	8:33	8:29	8:25	8:22	8:18	8:14	8:11	8:07	8:03	8:00	7:56	7:52	7:49	7:45	7:41	7:37	7:34	7:30	7:26	7:23	7:19	7:15	7:12	7:08	7:04	7:01	6:57	6:53	6:50

	Daylight (h)	Sunrise (AM)	Sunset (PM)
1	14.3	6:19	8:36
2	14.2	6:22	8:33
3	14.1	6:25	8:29
4	14.0	6:27	8:25
5	13.9	6:30	8:22
6	13.7	6:33	8:18
7	13.6	6:36	8:14
8	13.5	6:39	8:11
9	13.4	6:42	8:07
10	13.3	6:45	8:03
11	13.2	6:48	8:00
12	13.1	6:51	7:56
13	13.0	6:54	7:52
14	12.9	6:57	7:49
15	12.7	7:00	7:45
16	12.6	7:03	7:41
17	12.5	7:06	7:37
18	12.4	7:09	7:34
19	12.3	7:12	7:30
20	12.2	7:15	7:26
21	12.1	7:18	7:23
22	12.0	7:21	7:19
23	11.9	7:24	7:15
24	11.8	7:27	7:12
25	11.6	7:30	7:08
26	11.5	7:33	7:04
27	11.4	7:36	7:01
28	11.3	7:38	6:57
29	11.2	7:41	6:53
30	11.1	7:44	6:50

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 2.04 kWh/m².

For context, solar energy here swings from a low near 0.05 kWh/m² to a high of 5.21 kWh/m² in June across the year — September's 2.04 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)	2.7	2.6	2.6	2.5	2.5	2.4	2.4	2.4	2.3	2.3	2.2	2.2	2.1	2.1	2.0	2.0	2.0	1.9	1.9	1.8	1.8	1.8	1.7	1.7	1.6	1.6	1.6	1.5	1.5	1.5
Level	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Dim	Dim	Dim	Dim	Dim	Dim	Dim	Dim	Dim	Dim	Dim	Dim	Dim	Dim

	Solar energy (kWh/m²)	Level
1	2.7	Moderate
2	2.6	Moderate
3	2.6	Moderate
4	2.5	Moderate
5	2.5	Moderate
6	2.4	Moderate
7	2.4	Moderate
8	2.4	Moderate
9	2.3	Moderate
10	2.3	Moderate
11	2.2	Moderate
12	2.2	Moderate
13	2.1	Moderate
14	2.1	Moderate
15	2.0	Moderate
16	2.0	Moderate
17	2.0	Dim
18	1.9	Dim
19	1.9	Dim
20	1.8	Dim
21	1.8	Dim
22	1.8	Dim
23	1.7	Dim
24	1.7	Dim
25	1.6	Dim
26	1.6	Dim
27	1.6	Dim
28	1.5	Dim
29	1.5	Dim
30	1.5	Dim

Planning a trip in September

Is September a good time to visit Hafnarfjörður?

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

2.0

Sightseeing

4th-best month of the year

—

Beach & pool

never really warm enough

September is a weaker month for outdoor sightseeing in Hafnarfjörður.

What to pack for Hafnarfjörður in September

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

In September, Hafnarfjörður sees daytime highs around 11°C and nights near 6°C. Pack a warm layer and rain gear. About 18 days see rain.

a warm layerrain gear

Sea temperature near Hafnarfjörður in September

The nearest coast averages about 10°C in September — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea offshore is warmest in August at about 11°C and coldest in March near 5°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)	5	5	5	6	7	10	11	11	10	8	7	6
Comfort	Bracing	Bracing	Bracing	Bracing	Bracing	Bracing	Bracing	Bracing	Bracing	Bracing	Bracing	Bracing

	Sea temperature (°C)	Comfort
Jan	5	Bracing
Feb	5	Bracing
Mar	5	Bracing
Apr	6	Bracing
May	7	Bracing
Jun	10	Bracing
Jul	11	Bracing
Aug	11	Bracing
Sep	10	Bracing
Oct	8	Bracing
Nov	7	Bracing
Dec	6	Bracing

UV index in Hafnarfjörður 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 Hafnarfjörður peaks around June 21 at about 4 (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 3 months of the year.

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
UV index (midday)	0	0	1	2	4	5	4	3	2	1	0	0
Level	Low	Low	Low	Moderate	Moderate	Moderate	Moderate	Moderate	Low	Low	Low	Low

	UV index (midday)	Level
Jan	0	Low
Feb	0	Low
Mar	1	Low
Apr	2	Moderate
May	4	Moderate
Jun	5	Moderate
Jul	4	Moderate
Aug	3	Moderate
Sep	2	Low
Oct	1	Low
Nov	0	Low
Dec	0	Low

Location & terrain

Where is Hafnarfjörður?

Hafnarfjörður sits at 64.1°N, 21.9°W, 39 m above sea level, in Iceland. The nearest listed city is Kópavogur, 5.0 km away.

Topography around Hafnarfjörður

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

Within 3 km, the terrain around Hafnarfjörður has only modest variations in elevation — a maximum elevation change of 149 m around an average of 39 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 614 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,332 m.

The land around Hafnarfjörður is covered by grassland (53%) and artificial surfaces (24%) within 3 km, grassland (52%) and water (36%) within 16 km, and water (51%) and grassland (36%) within 80 km.

3 km

149 m

grassland 53%

16 km

614 m

grassland 52%

80 km

1,332 m

water 51%

treesshrubsgrasslandcroplandartificial surfacesbare terrainwaterwetlandmoss and lichen

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

September weather nearby: Kópavogur 5.0 km · Reykjavik 8.0 km · Keflavik 31 km · Reykjanesbær 31 km · Vik 161 km · Akureyri 256 km · Tórshavn 796 km · Isle of Lewis 1,053 km

Iceland travel facts

Travel advisory: Level 1; Exercise Normal Precautions
Power plugs: Type C / F; 230 V · 50 Hz
Prices: ≈ 118% of US; price level, 2025
GDP per capita: $98,323; 2025
Happiness: 7.5 / 10; World Happiness, 2025
Safe drinking water: 100%; of population, 2024
Homicide rate: 1.3; per 100k, 2023
Road deaths: 2; per 100k/yr, 2019
Income group: High; World Bank
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 Hafnarfjörður (64.0671°, -21.9377°, elevation 39 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	12	8
2	12	8
3	12	8
4	12	8
5	12	7
6	12	7
7	12	7
8	12	7
9	11	7
10	11	7
11	11	7
12	11	7
13	11	7
14	11	6
15	11	6
16	11	6
17	11	6
18	10	6
19	10	6
20	10	6
21	10	6
22	10	6
23	10	6
24	10	5
25	10	5
26	9	5
27	9	5
28	9	5
29	9	5
30	9	5

	Clearer (%)	Cloudier (%)
1	15	85
2	15	85
3	16	84
4	17	83
5	17	83
6	18	82
7	18	82
8	18	82
9	19	81
10	20	80
11	20	80
12	21	79
13	21	79
14	22	78
15	22	78
16	22	78
17	22	78
18	22	78
19	22	78
20	23	77
21	23	77
22	23	77
23	23	77
24	23	77
25	23	77
26	23	77
27	24	76
28	24	76
29	24	76
30	24	76

	Rain chance (%)	Snow chance (%)
1	57	0
2	58	0
3	58	0
4	58	0
5	58	0
6	58	0
7	58	0
8	58	0
9	58	0
10	57	0
11	57	0
12	57	0
13	57	0
14	57	0
15	57	0
16	57	0
17	58	1
18	58	1
19	58	1
20	58	1
21	58	1
22	59	1
23	59	1
24	59	2
25	59	2
26	59	2
27	59	3
28	59	3
29	59	3
30	58	4

	Dry (%)
1	100
2	100
3	100
4	100
5	100
6	100
7	100
8	100
9	100
10	100
11	100
12	100
13	100
14	100
15	100
16	100
17	100
18	100
19	100
20	100
21	100
22	100
23	100
24	100
25	100
26	100
27	100
28	100
29	100
30	100

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

	Clearer (%)	Cloudier (%)
1	15	85
2	15	85
3	16	84
4	17	83
5	17	83
6	18	82
7	18	82
8	18	82
9	19	81
10	20	80
11	20	80
12	21	79
13	21	79
14	22	78
15	22	78
16	22	78
17	22	78
18	22	78
19	22	78
20	23	77
21	23	77
22	23	77
23	23	77
24	23	77
25	23	77
26	23	77
27	24	76
28	24	76
29	24	76
30	24	76

	Rain chance (%)	Snow chance (%)
1	57	0
2	58	0
3	58	0
4	58	0
5	58	0
6	58	0
7	58	0
8	58	0
9	58	0
10	57	0
11	57	0
12	57	0
13	57	0
14	57	0
15	57	0
16	57	0
17	58	1
18	58	1
19	58	1
20	58	1
21	58	1
22	59	1
23	59	1
24	59	2
25	59	2
26	59	2
27	59	3
28	59	3
29	59	3
30	58	4

	Dry (%)
1	100
2	100
3	100
4	100
5	100
6	100
7	100
8	100
9	100
10	100
11	100
12	100
13	100
14	100
15	100
16	100
17	100
18	100
19	100
20	100
21	100
22	100
23	100
24	100
25	100
26	100
27	100
28	100
29	100
30	100

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

	Clearer (%)	Cloudier (%)
1	15	85
2	15	85
3	16	84
4	17	83
5	17	83
6	18	82
7	18	82
8	18	82
9	19	81
10	20	80
11	20	80
12	21	79
13	21	79
14	22	78
15	22	78
16	22	78
17	22	78
18	22	78
19	22	78
20	23	77
21	23	77
22	23	77
23	23	77
24	23	77
25	23	77
26	23	77
27	24	76
28	24	76
29	24	76
30	24	76

	Rain chance (%)	Snow chance (%)
1	57	0
2	58	0
3	58	0
4	58	0
5	58	0
6	58	0
7	58	0
8	58	0
9	58	0
10	57	0
11	57	0
12	57	0
13	57	0
14	57	0
15	57	0
16	57	0
17	58	1
18	58	1
19	58	1
20	58	1
21	58	1
22	59	1
23	59	1
24	59	2
25	59	2
26	59	2
27	59	3
28	59	3
29	59	3
30	58	4

	Dry (%)
1	100
2	100
3	100
4	100
5	100
6	100
7	100
8	100
9	100
10	100
11	100
12	100
13	100
14	100
15	100
16	100
17	100
18	100
19	100
20	100
21	100
22	100
23	100
24	100
25	100
26	100
27	100
28	100
29	100
30	100