Hoi An, Vietnam: vitamin D, best months and travel guide
Lantern-lit old town of tailors and cafés. Best for: couples, culture travellers, foodies.
The best months for vitamin D in Hoi An are February, March, May, when a full dose takes about 6 minutes at midday. Too hot in April and from June to August and rainy or stormy from September to January.
Hoi An month by month
| Month | Rating | Sun window | Peak UV | Full dose, age 30 | Afternoon high | Rainy days |
|---|---|---|---|---|---|---|
| January | Bad weather | 5.1 h | 5.3 | 10 min | 25°C | 20/30 |
| February | Excellent | 7.0 h | 7.2 | 7 min | 27°C | 10/30 |
| March | Excellent | 7.9 h | 8.4 | 6 min | 29°C | 8/30 |
| April | Too hot | 8.8 h | 9.1 | 6 min | 34°C | 0/30 |
| May | Excellent | 7.8 h | 8.3 | 6 min | 33°C | 11/30 |
| June | Too hot | 8.0 h | 8.2 | 7 min | 35°C | 17/30 |
| July | Too hot | 7.5 h | 7.7 | 7 min | 33°C | 17/30 |
| August | Too hot | 8.6 h | 8.8 | 6 min | 36°C | 15/30 |
| September | Bad weather | 6.8 h | 7.4 | 7 min | 32°C | 23/30 |
| October | Bad weather | 6.3 h | 6.9 | 8 min | 28°C | 27/30 |
| November | Bad weather | 5.6 h | 5.7 | 9 min | 27°C | 22/30 |
| December | Bad weather | 2.1 h | 2.8 | 19 min | 24°C | 28/30 |
Sun window is the number of hours a day with UV Index 2.5 or higher. Full dose is the minutes at midday for about 1,000 IU of vitamin D with a quarter of the body bare, for skin type III. Rainy days are days with at least 1 mm out of 30.
What to expect in Hoi An
Lantern-lit old town of tailors and cafés. Different climates in the north, centre and south. The central coast (Da Nang, Hoi An) is best from February to May; the south is dry from December to April; typhoons can hit the centre from September to November.
In Hoi An afternoon highs average from 24°C in December to 36°C in August. The wettest month is December (about 28 rainy days out of 30) and the driest is April (0). Midday UV peaks at 9.1 in April, which is very strong, so protect your skin.
A well-preserved ancient port, near the ruins of My Son (Wikivoyage, CC BY-SA 4.0)
More about Vietnam · Vietnam in March · Best places in March
Questions about Hoi An
When is the best time to visit Hoi An for vitamin D?
The best months for vitamin D in Hoi An are February, March, May, when a full dose takes about 6 minutes at midday.
What is the weather like in Hoi An?
Afternoon highs average from 24°C in December to 36°C in August. The wettest month is December, with about 28 rainy days out of 30.
Which months should I avoid in Hoi An?
For a beach stay, avoid the months when it is too hot in April and from June to August and rainy or stormy from September to January.