Month by month
| Month | Afternoon | Sea | Rain | Verdict |
|---|---|---|---|---|
| January | 19.2 °C | 20.2 °C | 9 days | Pleasant — a good time to go |
| February | 19.8 °C | 19.2 °C | 8 days | Pleasant — a good time to go |
| March | 22.9 °C | 20.4 °C | 11 days | Pleasant — a good time to go |
| April | 26.2 °C | 23.5 °C | 12 days | Pleasant — a good time to go |
| May | 29 °C | 27.6 °C | 17 days | Possible, with trade-offs |
| June | 30.9 °C | 30 °C | 18 days | Unfavourable season |
| July | 30.7 °C | 30.4 °C | 21 days | Unfavourable season |
| August | 30.3 °C | 30.3 °C | 24 days | Unfavourable season |
| September | 29.7 °C | 30 °C | 22 days | Unfavourable season |
| October | 27.5 °C | 28.4 °C | 14 days | Ideal — one of the best times of year |
| November | 24.9 °C | 25.9 °C | 9 days | Ideal — one of the best times of year |
| December | 20.4 °C | 22.5 °C | 6 days | Pleasant — a good time to go |
Nearby in June
Before you go
Three things to check once you have picked your dates.
Entry
No visa needed for stays of up to 45 days. Passport valid for at least 6 months. Passport needs 2 blank pages and no damage; check the exit date stamped on arrival; e-visa (90 days, multiple entry) for longer stays.
For a British passport, per the UK Foreign Office on 26 June 2026. Rules change: check before booking.
Safety
No specific restrictions
Usual precautions apply.
Official advice updated 26 June 2026
Health
Vaccines · typhoid recommended for most travellers; hepatitis A and hepatitis B if you are not already vaccinated; Japanese encephalitis depending on activities and areas visited. Routine vaccines up to date (measles in particular).
Yellow fever · No yellow fever locally, vaccine not recommended. No entry requirement.
Malaria · Present. Areas: Rural areas only; rare cases in the Mekong and Red River Deltas None in the cities of Da Nang, Hai Phong, Hanoi, Ho Chi Minh City (Saigon), Nha Trang, and Quy Nhon. Preventive medication recommended: Provinces of Bình Dương, Bình Phước, Đắk Lắk, Đắk Nông, Gia Lai, Khánh Hòa, Kon Tum, Lâm Đồng, Ninh Thuận, Tây Ninh: Atovaquone-proguanil, doxycycline, tafenoquine All other areas with malaria transmission (except Mekong and Red River Deltas): Atovaquone-proguanil, doxycycline, mefloquine, tafenoquine Mekong and Red River Deltas: No chemoprophylaxis recommended (insect bite precautions and mosquito avoidance only) — prescribed before departure.
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 Cat Ba in June?
The sea averages 30°C in June — yes, pleasant swimming.
How hot is Cat Ba in June?
Expect 30.9°C in the afternoon and 27.9°C at night, averaged over the last 10 years.
Does it rain a lot in Cat Ba in June?
Around 18 days with rain (≥ 1 mm) in the month — 60% of days.