Reykjavík weather in September
Temperature, sea and sunshine in September: long-term averages from 30 years of weather data, not a forecast.
Holiday weather in September
Poor
Best time to visit: July
What is the weather like in Reykjavík in September?
In September, Reykjavík is cool: daytime highs average 10 °C, and nights cool down to about 5 °C. The sea averages 10.2 °C – swimming is only for the hardy. The sun is scarce, with only about 4 hours a day. It rains often – on about 18 days, adding up to 134 mm. All in all, September is not an ideal month for a holiday in Reykjavík.
September compared
How the weather changes from August to October. Tap a month to open it.
| AugustAug | SeptemberSep | OctoberOct | |
|---|---|---|---|
| Score | 45 | 15 | 6 |
| Day | 14° | 10° | 6° |
| Night | 8° | 5° | 1° |
| Sea | 12° | 10° | 9° |
| Sun | 5 h | 4 h | 3 h |
| Rain days | 15 | 18 | 15 |
More details for September
- Daylight
- 13 h 11 min06:48 – 19:58
- UV index
- 2 · lowclear sky, noon (estimate)All months
- Muggy days
- 0 daysdew point 18 °C or more
- Wind
- 26 km/haverage daily peak
- Cloud cover
- 77 %on average
- Hot days
- 0 days30 °C or more
- Snow days
- 0 days1 cm or more of fresh snow
- Time zone
- UTC+0Atlantic/Reykjavik
How the score comes together
- Temperatureweight 50 %24 %
- Sunshineweight 20 %15 %
- Few rainy daysweight 30 %1 %
Each factor is rated from 0 to 100 % and weighted for the travel style “Nature escape”.
What to pack in September
- A jumper for the evenings
- Rain jacket or umbrella
Reykjavík in September: quick answers
Is Reykjavík hot in September?
No. In September, Reykjavík is cool: daytime highs average 10 °C and nights drop to about 5 °C.
Can you swim in Reykjavík in September?
Only if you don't mind cold water: in September the sea averages just 10.2 °C. Comfortable swimming temperatures are not reached at any time of year.
Does it rain much in Reykjavík in September?
It rains often – on about 18 days, adding up to 134 mm.
Reykjavík month by month
The whole year in ReykjavíkAll destinations: IcelandWhere to go in SeptemberSea temperature in September
Climate averages 1996–2025, not a forecast. Data: Copernicus ERA5 / ERA5-Land via Open-Meteo.com (CC BY 4.0), NOAA OISST, WMO 1991–2020 (NOAA NCEI), GeoNames (CC BY 4.0)