Month by month
| Month | Afternoon | Sea | Rain | Verdict |
|---|---|---|---|---|
| January | 2.2 °C | 3.9 °C | 13 days | Unfavourable season |
| February | 3 °C | 3 °C | 11 days | Unfavourable season |
| March | 5.8 °C | 3.9 °C | 11 days | Unfavourable season |
| April | 10.5 °C | 7 °C | 9 days | Unfavourable season |
| May | 16.1 °C | 11.6 °C | 12 days | Possible, with trade-offs |
| June | 20 °C | 15.9 °C | 13 days | Pleasant — a good time to go |
| July | 20.5 °C | 17.8 °C | 15 days | Possible, with trade-offs |
| August | 19.7 °C | 18.2 °C | 15 days | Possible, with trade-offs |
| September | 16.6 °C | 16.3 °C | 14 days | Possible, with trade-offs |
| October | 10.9 °C | 12.4 °C | 14 days | Unfavourable season |
| November | 6.2 °C | 9.1 °C | 13 days | Unfavourable season |
| December | 3.4 °C | 6 °C | 15 days | Unfavourable season |
Before you go
Three things to check once you have picked your dates.
Entry
Sweden is in the European Union. Entry rules depend on your nationality — check before booking.
Safety
No specific restrictions
Usual precautions apply.
Official advice updated 11 August 2026
Health
Recommended vaccinations, water quality, mosquitoes: advice depends on the country and the season. Some vaccines need time before departure.
Beau Fixe is not a safety or health authority. These notes summarise public advisories and link to their source; only the competent authorities are authoritative. Alert levels: Foreign, Commonwealth & Development Office (gov.uk), Open Government Licence v3.0.
FAQ
Can you swim in Uddevalla in September?
The sea averages 16.3°C in September — too cold for most swimmers.
How hot is Uddevalla in September?
Expect 16.6°C in the afternoon and 10.5°C at night, averaged over the last 10 years.
Does it rain a lot in Uddevalla in September?
Around 14 days with rain (≥ 1 mm) in the month — 45% of days.