Month by month
| Month | Afternoon | Sea | Rain | Verdict |
|---|---|---|---|---|
| January | 22.4 °C | 19.9 °C | 9 days | Pleasant — a good time to go |
| February | 21.8 °C | 20.1 °C | 8 days | Pleasant — a good time to go |
| March | 20.1 °C | 19.2 °C | 10 days | Pleasant — a good time to go |
| April | 17.5 °C | 17.7 °C | 11 days | Possible, with trade-offs |
| May | 15.2 °C | 15.9 °C | 11 days | Possible, with trade-offs |
| June | 13.1 °C | 14.1 °C | 11 days | Possible, with trade-offs |
| July | 12.2 °C | 12.7 °C | 10 days | Possible, with trade-offs |
| August | 12.8 °C | 12.2 °C | 12 days | Possible, with trade-offs |
| September | 14.3 °C | 12.9 °C | 13 days | Possible, with trade-offs |
| October | 16.4 °C | 14.4 °C | 12 days | Possible, with trade-offs |
| November | 18.3 °C | 16.4 °C | 13 days | Possible, with trade-offs |
| December | 20.7 °C | 18.5 °C | 13 days | Pleasant — a good time to go |
Before you go
Three things to check once you have picked your dates.
Entry
Entry rules depend on your nationality and change often. Check them before booking.
Safety
No specific restrictions
Usual precautions apply.
Official advice updated 19 March 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 Nelson in September?
The sea averages 12.9°C in September — too cold for most swimmers.
How hot is Nelson in September?
Expect 14.3°C in the afternoon and 7°C at night, averaged over the last 10 years.
Does it rain a lot in Nelson in September?
Around 13 days with rain (≥ 1 mm) in the month — 43% of days.