Karlskrona 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: April – August
What is the weather like in Karlskrona in September?
In September, Karlskrona is mild: daytime highs average 16 °C, and nights cool down to about 12 °C. The sea averages 15.4 °C – swimming is only for the hardy. The sun shines for around 7 hours a day. Rain falls on about 9 days, adding up to 48 mm. All in all, September is not an ideal month for a holiday in Karlskrona.
September compared
How the weather changes from August to October. Tap a month to open it.
| AugustAug | SeptemberSep | OctoberOct | |
|---|---|---|---|
| Score | 34 | 26 | 12 |
| Day | 20° | 16° | 11° |
| Night | 15° | 12° | 8° |
| Sea | 18° | 15° | 12° |
| Sun | 9 h | 7 h | 4 h |
| Rain days | 11 | 9 | 11 |
More details for September
- Daylight
- 12 h 52 min06:27 – 19:19
- UV index
- 3 · moderateclear sky, noon (estimate)All months
- Muggy days
- 0 daysdew point 18 °C or moreAll months
- Wind
- 22 km/haverage daily peakAll months
- Cloud cover
- 61 %on averageAll months
- Hot days
- 0 days30 °C or more
- Snow days
- 0 days1 cm or more of fresh snowAll months
- Time zone
- UTC+2Europe/Stockholm
How the score comes together
- Temperatureweight 35 %0 %
- Seaweight 25 %0 %
- Sunshineweight 20 %60 %
- Few rainy daysweight 20 %68 %
Each factor is rated from 0 to 100 % and weighted for the travel style “Sun, sea & sand”.
What to pack in September
- A jumper for the evenings
- Rain jacket or umbrella
Karlskrona in September: quick answers
Is Karlskrona hot in September?
No. In September, Karlskrona is mild: daytime highs average 16 °C and nights drop to about 12 °C.
Can you swim in Karlskrona in September?
Only if you don't mind cold water: in September the sea averages just 15.4 °C. Comfortable swimming temperatures are not reached at any time of year.
Does it rain much in Karlskrona in September?
Rain falls on about 9 days, adding up to 48 mm.
Karlskrona month by month
The whole year in KarlskronaAll destinations: SwedenWhere 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). Sources & licences