Month by month
| Month | Afternoon | Sea | Rain | Verdict |
|---|---|---|---|---|
| January | 4.8 °C | 4.4 °C | 13 days | Unfavourable season |
| February | 6.6 °C | 4.1 °C | 13 days | Unfavourable season |
| March | 9.3 °C | 5.6 °C | 11 days | Unfavourable season |
| April | 13.2 °C | 8.9 °C | 11 days | Possible, with trade-offs |
| May | 17.9 °C | 13 °C | 12 days | Possible, with trade-offs |
| June | 22.2 °C | 17 °C | 11 days | Pleasant — a good time to go |
| July | 22.5 °C | 18.9 °C | 15 days | Possible, with trade-offs |
| August | 23.3 °C | 19.6 °C | 13 days | Pleasant — a good time to go |
| September | 19.6 °C | 17.2 °C | 10 days | Pleasant — a good time to go |
| October | 14.4 °C | 13 °C | 14 days | Possible, with trade-offs |
| November | 8.6 °C | 9 °C | 14 days | Unfavourable season |
| December | 6.2 °C | 5.7 °C | 15 days | Unfavourable season |
Before you go
Three things to check once you have picked your dates.
Entry
Germany 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 Altona in September?
The sea averages 17.2°C in September — too cold for most swimmers.
How hot is Altona in September?
Expect 19.6°C in the afternoon and 11.6°C at night, averaged over the last 10 years.
Does it rain a lot in Altona in September?
Around 10 days with rain (≥ 1 mm) in the month — 33% of days.