Vitamin D in Saint Martin in September: sun, UV and what to expect
Bad weather Bad weather: September is a peak month for tropical storms here, so a beach stay is not recommended. If you still go, check forecasts and travel insurance.
8.4 hsun window (UV 2.5+)
8.4peak UV Index
6 minto a full dose
30°Cafternoon high
16/30rainy days
30/30sunny days
Open Saint Martin for September on the map Find stays in Saint Martin
How long in the sun in September?
- If you travel anyway, plan your sun session around midday (roughly 11:00 to 15:00), when the UV Index peaks at about 8.4. With about a quarter of your skin bare, a full dose takes around 6 minutes for skin type III at age 30, and about 12 minutes at age 65.
- Stop well before your skin turns pink. At this UV level skin type III can start to burn after about 24 minutes of midday sun, so cover up, find shade and use SPF 30+ on skin that stays out.
- On clear days the UV Index reaches about 8.5, which is very strong. Keep sessions short and protect the rest of the day.
- Water, sand and light surfaces reflect UV, so at the beach you get a little more sun than the number suggests, for the good and the bad.
| Skin type | Full dose, age 30 | Full dose, age 65 | Time to burn |
|---|---|---|---|
| Type I | 4 min | 8 min | 16 min |
| Type II | 5 min | 10 min | 20 min |
| Type III | 6 min | 12 min | 24 min |
| Type IV | 10 min | 18 min | 36 min |
| Type V | 13 min | 24 min | 48 min |
| Type VI | 21 min | 40 min | 79 min |
Minutes at midday for about 1,000 IU of vitamin D with a quarter of the body bare, at Grand Case, the median coastal place. Time to burn is the time to reach one minimal erythemal dose and does not depend on age. A rough planning guide, not medical advice.
Places in Saint Martin in September
| Place | Rating | Sun window | Full dose | Afternoon high | Rainy days |
|---|---|---|---|---|---|
| Pic Paradis | Bad weather | 8.4 h | 6 min | 29°C | 16/30 |
| Marigot | Bad weather | 8.4 h | 6 min | 30°C | 16/30 |
| Grand Case | Bad weather | 8.4 h | 6 min | 30°C | 16/30 |
| Orient Bay | Bad weather | 8.4 h | 6 min | 30°C | 16/30 |
| Anse Marcel | Bad weather | 8.4 h | 6 min | 30°C | 16/30 |
Other months in Saint Martin
- Jan Excellent
- Feb Excellent
- Mar Excellent
- Apr Excellent
- May Excellent
- Jun Excellent
- Jul Excellent
- Aug Bad weather
- Sep Bad weather
- Oct Excellent
- Nov Good
- Dec Good
Best months: October to July. Full Saint Martin guide