Lillestrøm weather in September

In September, Lillestrøm sees average daytime highs of 15°C and overnight lows near 7°C, with 81 mm of rain across 10.4 wet days and about 12.6 hours of daylight. It is the 5th-warmest and 6th-wettest month of the year here.

Highs ease over the month, from about 17°C in the first days to 13°C by the end. The sky is clear or mostly clear about 22% of the time in September, and the air most often feels dry.

Daylight stretches from about 13 h 54 min at the start of September to 11 h 12 min by month's end. Set against the rest of the year, September is Lillestrøm's 4th-clearest and 2nd-windiest month. For the whole year in context, see Lillestrøm's year-round climate.

Daytime high
15°
5th warmest
Overnight low
9th coldest
Rainfall
81 mm
10.4 wet days
Daylight
12 h 30 min
5:54 AM – 6:26 PM
Cloud cover
66%
4th clearest
Wind
10 km/h
2nd windiest
Solar energy
2.48 kWh/m²
Travel score
4.4
out of 10

Lillestrøm is town in Lillestrøm Municipality, Norway.

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 13°C by the end.

A typical September day in Lillestrøm reaches about 15°C in the afternoon and slips back to 7°C overnight — a 8°C spread between the day's warmth and the night's chill. On most days the high lands between 12°C and 19°C. Set against its neighbours, September runs about 5°C cooler than August and about 6°C warmer than October.

10°15°20°25°151015202530
Avg high (°C)Avg low (°C)
1189
2179
3179
4179
5179
6179
7179
8168
9168
10168
11168
12168
13168
14158
15158
16157
17157
18157
19157
20147
21147
22147
23146
24146
25136
26136
27136
28136
29136
30125

How September really feels in Lillestrøm

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.

Lillestrøm weather by month

How September compares with the rest of the year at a glance. September is the 5th-warmest and 6th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan-1° / -6°6510.59.86.40.0
Feb-0° / -6°488.27.98.60.0
Mar / -4°4986.511.30.2
Apr10° / 539.12.914.12.2
May15° / 7411.60.816.74.4
Jun19° / 9111.9018.35.6
Jul21° / 12°9412.6017.76.0
Aug20° / 11°10413.6015.45.7
Sep15° / 8110.4012.64.4
Oct / 8411.41.39.81.6
Nov / -1°8411.65.67.20.0
Dec-0° / -5°6610.87.75.70.0

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 22% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 17% of September, with mostly cloudy or overcast conditions the remaining 61%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
13961
23961
34060
44060
54060
64060
74060
84060
94159
104159
114159
124060
134060
144060
154060
164060
174060
184060
193961
203961
213961
223862
233862
243862
253763
263763
273763
283664
293664
303565

Chance of precipitation in September

Any precipitation

Lillestrøm gets around 81 mm of rain over 10.4 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 36% and peaks near 37% on the wettest days.

0%10%20%30%40%50%151015202530
Rain chance (%)
137
237
337
437
536
637
737
837
937
1037
1137
1237
1337
1436
1536
1636
1735
1835
1934
2034
2134
2234
2334
2434
2534
2635
2735
2836
2936
3036

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 96% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)
188102
29091
39181
49271
59271
69361
79460
89550
99550
109550
119640
129640
139640
149730
159730
169730
179730
189820
199820
209820
219820
229910
239910
249910
259910
269910
279910
289910
299910
309910

Wind in September

Winds average 10 km/h in September.

Across September, daily wind ranges from about 10 km/h on the calmest days to 11 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202530
Wind speed (km/h)Feels
110calm
210calm
310calm
410calm
510calm
610calm
710calm
810calm
910calm
1011calm
1111calm
1211calm
1311calm
1411calm
1511calm
1610calm
1710calm
1810calm
1910calm
2010calm
2110calm
2210calm
2310calm
2410calm
2510calm
2610calm
2710calm
2810calm
2910calm
3010calm

Sunrise & sunset in September

DaylightNight

Daylight runs from about 13 h 54 min 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 162 minutes over September. Sunrise moves from 5:18 AM to 6:28 AM, and sunset from 7:13 PM to 5:42 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
113.95:187:13
213.85:207:10
313.75:237:07
413.65:257:04
513.65:287:01
613.55:306:58
713.45:326:55
813.35:356:51
913.25:376:48
1013.15:406:45
1113.05:426:42
1212.95:446:39
1312.85:476:36
1412.75:496:32
1512.65:526:29
1612.55:546:26
1712.45:576:23
1812.35:596:20
1912.36:016:17
2012.26:046:14
2112.16:066:10
2212.06:096:07
2311.96:116:04
2411.86:136:01
2511.76:165:58
2611.66:185:55
2711.56:215:51
2811.46:235:48
2911.36:265:45
3011.26:285:42

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 2.48 kWh/m².

For context, solar energy here swings from a low near 0.19 kWh/m² to a high of 5.56 kWh/m² in June across the year — September's 2.48 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
252.0Moderate
261.9Dim
271.9Dim
281.9Dim
291.8Dim
301.8Dim
Planning a trip in September

Is September a good time to visit Lillestrøm?

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

4.4
Sightseeing
4th-best month of the year
0.5
Beach & pool
5th-best month of the year

September is a reasonable time to visit Lillestrøm for sightseeing.

What to pack for Lillestrøm in September

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

In September, Lillestrøm sees daytime highs around 15°C and nights near 7°C. Worth packing: a warm layer and rain gear. About 10 days see rain.

a warm layerrain gear

Sea temperature near Lillestrøm 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 69 km away) is warmest in August at about 18°C and coldest in February near 3°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
Jan4Bracing
Feb3Bracing
Mar3Bracing
Apr6Bracing
May11Bracing
Jun15Cool
Jul18Cool
Aug18Cool
Sep15Cool
Oct12Bracing
Nov9Bracing
Dec6Bracing

UV index in Lillestrøm in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 3. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Lillestrøm peaks around June 23 at about 5 (moderate) — a little sun protection helps at midday. It bottoms out near January 1 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 5Jan 1UV 0
UV index (midday)Level
Jan0Low
Feb1Low
Mar2Low
Apr3Moderate
May4Moderate
Jun5Moderate
Jul5Moderate
Aug4Moderate
Sep3Moderate
Oct1Low
Nov0Low
Dec0Low
Location & terrain

Where is Lillestrøm?

Lillestrøm sits at 60.0°N, 11.0°E, 116 m above sea level, in Norway. The nearest listed city is Oslo, 18 km away.

Topography around Lillestrøm

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

Within 3 km, the terrain around Lillestrøm has only modest variations in elevation — a maximum elevation change of 214 m around an average of 135 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 444 m; within 80 km, large variations in elevation — a maximum elevation change of 1,025 m.

The land around Lillestrøm is covered by trees (36%), artificial surfaces (29%) and cropland (23%) within 3 km, trees (61%) within 16 km, and trees (75%) within 80 km.

3 km
214 m
16 km
444 m
80 km
1,025 m
treesgrasslandcroplandartificial surfaceswater
September weather nearby: Oslo 18 km · Asker 37 km · Drammen 53 km · Moss 62 km · Horten 68 km · Sarpsborg 75 km · Fredrikstad 82 km · Kongsberg 84 km

Norway travel facts

Travel advisory
Level 1
Exercise Normal Precautions
Power plugs
Type C / F
230 V · 50 Hz
Prices
≈ 91% of US
price level, 2025
GDP per capita
$94,594
2025
Happiness
7.2 / 10
World Happiness, 2025
Safe drinking water
99%
of population, 2024
Homicide rate
0.7
per 100k, 2023
Road deaths
2.1
per 100k/yr, 2019
Income group
High
World Bank
English
Very high
EF EPI 613
Religion
Church of Norway 68%other Christian 4%Muslim 3%Roman Catholic 3%

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 Lillestrøm (59.956°, 11.0492°, elevation 116 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).