Month by month
| Month | Afternoon | Sea | Rain | Verdict |
|---|---|---|---|---|
| January | 26 °C | 26.9 °C | 11 days | Ideal — one of the best times of year |
| February | 25.7 °C | 26.7 °C | 12 days | Ideal — one of the best times of year |
| March | 25.7 °C | 26.6 °C | 8 days | Ideal — one of the best times of year |
| April | 26.2 °C | 27.1 °C | 11 days | Ideal — one of the best times of year |
| May | 27.1 °C | 27.8 °C | 12 days | Ideal — one of the best times of year |
| June | 27.9 °C | 28.4 °C | 13 days | Ideal — one of the best times of year |
| July | 28.2 °C | 28.7 °C | 15 days | Possible, with trade-offs |
| August | 28.5 °C | 29 °C | 17 days | Possible, with trade-offs |
| September | 28.7 °C | 29.5 °C | 17 days | Possible, with trade-offs |
| October | 28.4 °C | 29.3 °C | 18 days | Possible, with trade-offs |
| November | 27.7 °C | 28.7 °C | 17 days | Possible, with trade-offs |
| December | 26.9 °C | 27.8 °C | 14 days | Ideal — one of the best times of year |
Nearby in September
Before you go
Three things to check once you have picked your dates.
Entry
No visa, but an electronic travel authorisation (ESTA) must be obtained online before departure. Passport valid until your return date. Source is the FCDO USA page: ESTA required under the Visa Waiver Program (apply online before travel); not available after travel to Cuba since 2021.
For a British passport, per the UK Foreign Office on 18 August 2026. Rules change: check before booking.
Safety
No specific restrictions
Usual precautions apply.
Official advice updated 18 August 2026
Health
Vaccines · hepatitis A and hepatitis B if you are not already vaccinated. Routine vaccines up to date (measles in particular).
Yellow fever · No yellow fever locally, vaccine not recommended. No entry requirement.
Malaria · None.
Mosquitoes · dengue and Zika reported: protect yourself from bites.
Per the CDC (page reviewed 25 August 2026); see a travel clinic a few weeks before departure.
Beau Fixe is not a safety or health authority. These notes summarise dated public texts and link to their source: France Diplomatie (Licence Ouverte 2.0), Foreign, Commonwealth & Development Office (gov.uk, Open Government Licence v3.0), Centers for Disease Control and Prevention (Source: CDC). Only the competent authorities are authoritative.
FAQ
Can you swim in Charlotte Amalie in September?
The sea averages 29.5°C in September — yes, pleasant swimming.
How hot is Charlotte Amalie in September?
Expect 28.7°C in the afternoon and 26.9°C at night, averaged over the last 10 years.
Does it rain a lot in Charlotte Amalie in September?
Around 17 days with rain (≥ 1 mm) in the month — 56% of days.