Vitamin D in Cook Islands in September: sun, UV and what to expect
Excellent Excellent. The sun is strong for most of the day in Cook Islands in September, so a full vitamin D dose takes only about 7 minutes at midday, and the usable window lasts 7.0 hours a day.
7.0 hsun window (UV 2.5+)
7.2peak UV Index
7 minto a full dose
23°Cafternoon high
11/30rainy days
25/30sunny days
Best places in Cook Islands in September: Aitutaki (excellent), Atiu (excellent), Rarotonga (excellent), Avarua (excellent), Muri (excellent).
Open Cook Islands for September on the map Find stays in Cook Islands
How long in the sun in September?
- Plan your sun session around midday (roughly 11:00 to 15:00), when the UV Index peaks at about 7.2. With about a quarter of your skin bare, a full dose takes around 7 minutes for skin type III at age 30, and about 14 minutes at age 65.
- Stop well before your skin turns pink. At this UV level skin type III can start to burn after about 28 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 8.1, 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 | 5 min | 9 min | 19 min |
| Type II | 6 min | 12 min | 23 min |
| Type III | 7 min | 14 min | 28 min |
| Type IV | 11 min | 21 min | 42 min |
| Type V | 15 min | 28 min | 56 min |
| Type VI | 25 min | 46 min | 93 min |
Minutes at midday for about 1,000 IU of vitamin D with a quarter of the body bare, at Rarotonga, 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 Cook Islands in September
Other months in Cook Islands
- Jan Bad weather
- Feb Bad weather
- Mar Bad weather
- Apr Excellent
- May Good
- Jun Good
- Jul Good
- Aug Good
- Sep Excellent
- Oct Excellent
- Nov Excellent
- Dec Bad weather
Best months: April to November. Full Cook Islands guide