Vitamin D in Maryland in July: sun, UV and what to expect
Excellent Excellent. The sun is strong for most of the day in Maryland in July, so a full vitamin D dose takes only about 7 minutes at midday, and the usable window lasts 8.5 hours a day.
8.5 hsun window (UV 2.5+)
7.3peak UV Index
7 minto a full dose
31°Cafternoon high
5/30rainy days
28/30sunny days
Best places in Maryland in July: Assateague Island (excellent), Ocean City (excellent), St. Michaels (excellent), Annapolis (excellent), Baltimore (excellent).
How long in the sun in July?
- Plan your sun session around midday (roughly 11:00 to 15:00), when the UV Index peaks at about 7.3. 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 27 minutes of midday sun, so cover up, find shade and use SPF 30+ on skin that stays out.
- 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 | 18 min |
| Type II | 6 min | 11 min | 23 min |
| Type III | 7 min | 14 min | 27 min |
| Type IV | 11 min | 21 min | 41 min |
| Type V | 15 min | 27 min | 55 min |
| Type VI | 24 min | 46 min | 91 min |
Minutes at midday for about 1,000 IU of vitamin D with a quarter of the body bare, at St. Michaels, 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 Maryland in July
| Place | Rating | Sun window | Full dose | Afternoon high | Rainy days |
|---|---|---|---|---|---|
| Assateague Island | Excellent | 8.5 h | 7 min | 28°C | 6/30 |
| Ocean City | Excellent | 8.7 h | 7 min | 23°C | 5/30 |
| St. Michaels | Excellent | 8.5 h | 7 min | 31°C | 5/30 |
| Annapolis | Excellent | 8.3 h | 7 min | 32°C | 7/30 |
| Baltimore | Excellent | 8.2 h | 7 min | 33°C | 8/30 |
Other months in Maryland
- Jan Too cold
- Feb Too cold
- Mar Too cold
- Apr Too cold
- May Good
- Jun Excellent
- Jul Excellent
- Aug Excellent
- Sep Good
- Oct Too cold
- Nov Too cold
- Dec Too cold
Best months: May to September. Full Maryland guide