Flagstaff, Arizona, USA UV Index in May
The average UV index in Flagstaff, Arizona, USA in May is about 6.9 (High), peaking near 10.8 at midday on clear days. Fair skin (Type II) can burn in roughly 13 minutes without sunscreen. SPF 30–50 sunscreen, a hat and sunglasses are essential. Seek shade between 11am and 3pm.
What is the UV index in Flagstaff, Arizona, USA in May?
Average UV
6.9
High
Midday Peak
10.8
Clear-sky estimate
Fair Skin Burn Time
13 min
Type II, no sunscreen
How long can you stay in the sun in Flagstaff, Arizona, USA in May?
| Skin type | Time to first burn | With SPF 30 |
|---|---|---|
| Type 1 | 9 min | up to 240 min |
| Type 2 | 13 min | up to 240 min |
| Type 3 | 22 min | up to 240 min |
| Type 4 | 35 min | up to 240 min |
| Type 5 | 52 min | up to 240 min |
| Type 6 | 78 min | up to 240 min |
Estimates based on Flagstaff, Arizona, USA's latitude and typical May sun angle. Cloud cover, altitude and reflection from water or sand can raise or lower the real UV. Check the live forecast before long days outside.
Flagstaff, Arizona, USA UV Index by Month
When is the UV index highest and lowest in Flagstaff, Arizona, USA?
Highest: June (about 7). Lowest: December (about 4.8).
| Month | Average UV | Midday peak | Level | Fair skin burn |
|---|---|---|---|---|
| January | 5 | 7.9 | Moderate | 18 min |
| February | 5.5 | 8.6 | Moderate | 16 min |
| March | 6.1 | 9.6 | High | 15 min |
| April | 6.7 | 10.5 | High | 13 min |
| May | 6.9 | 10.8 | High | 13 min |
| June | 7 | 11 | High | 13 min |
| July | 7 | 11 | High | 13 min |
| August | 6.8 | 10.7 | High | 13 min |
| September | 6.4 | 10.1 | High | 14 min |
| October | 5.8 | 9.1 | Moderate | 16 min |
| November | 5.1 | 8 | Moderate | 18 min |
| December | 4.8 | 7.5 | Moderate | 19 min |
Common questions about UV in Flagstaff, Arizona, USA in May
Do you need sunscreen in Flagstaff, Arizona, USA in May?
Yes. A UV index of 6.9 is High, so use SPF 30+ on exposed skin between 10am and 4pm and reapply every two hours.
Can you tan in Flagstaff, Arizona, USA in May?
Yes, UV of 6.9 is strong enough to tan. Fair skin can burn in about 13 minutes, so build exposure slowly and use sunscreen.
What time of day is UV strongest in Flagstaff, Arizona, USA?
UV peaks around solar noon, roughly 11am to 2pm local time, when it can reach about 10.8 in May. Mornings and late afternoons are safest.
Is May a good month to visit Flagstaff, Arizona, USA for the sun?
May averages UV 6.9, compared with a yearly high of 7 in June and a low of 4.8 in December. Darker skin (Type VI) can burn in about 78 minutes at this level.