UV Index in Phoenix, United States

Last updated: July 2, 2025

In Phoenix, United States, awareness of the UV Index is crucial for protecting your skin from harmful sun exposure. Understanding UV levels not only helps prevent painful sunburns but also plays a significant role in maintaining long-term skin health. With its BWh climate, Phoenix experiences high UV exposure throughout the year, especially during midday when the index can reach extremes of 11. It’s essential for residents and visitors alike to stay informed about these levels to enjoy the sun safely while minimizing the risk of skin damage.

Hourly UV Index in Phoenix

The UV Index throughout the day showcases a dramatic rise and fall that is vital for sun safety. Starting at 07:00, it begins with a low reading of 1, but by 08:00, it climbs to 3. The intensity peaks between 11:00 and 13:00, soaring to an impressive 11, indicating a significant risk for harm without sun protection. As the afternoon progresses, the index starts to decline, dipping to 10 at 14:00, then falling further to 7 by 15:00. As evening approaches, the UV Index drops quickly, reaching a low of 1 by 18:00 and remaining there until 19:00. To enjoy the outdoors safely, be sure to slather on the sunscreen during that midday surge!

Average solar exposure data for the current time of the year. Actual values may vary and depend on many factors, such as cloud cover, vegetation cover, surface type, etc.
Time	UVI	Category	Time to Burn
07:00	1	low	45 min
08:00	3	moderate	30 min
09:00	5	moderate	30 min
10:00	8	very high	15 min
11:00	10	very high	15 min
12:00	11	extreme	10 min
13:00	11	extreme	10 min
14:00	10	very high	15 min
15:00	7	high	25 min
16:00	5	moderate	30 min
17:00	3	moderate	30 min
18:00	1	low	45 min
19:00	1	low	45 min

Monthly UV Index Trends in Phoenix

Throughout the year, the UV Index demonstrates notable seasonal changes, with the highest risk months occurring from March to September. During this period, UV Index values peak at 11 (extreme) in May, June, July, and August, resulting in a significantly reduced burn time of just 10 minutes for unprotected skin. Conversely, the lower risk months are from November to February, where the index ranges from 4 to 6 (moderate to high) and burn times increase to 25-30 minutes. Visitors and residents should exercise caution during the peak summer months by applying sunscreen, wearing protective clothing, and seeking shade, especially between the hours of 10 AM and 4 PM when UV exposure is at its highest.

Monthly Maximum UV Index for Phoenix, United States

The monthly maximum UV Index (UVI) represents the highest UV radiation level recorded each month in Phoenix. It measures the strength of ultraviolet radiation from the sun and helps assess the risk of sunburn and UV-related health issues.

Data source: Statistical UV Index data for Phoenix, based on information from the Copernicus Climate Change Service.

UV Risk Categories

Extreme (11+): Avoid the sun, stay in shade.
Very High (8-10): Limit sun exposure.
High (6-7): Use SPF 30+ and protective clothing.
Moderate (3-5): Midday shade recommended.
Low (0-2): No protection needed.

Compare Phoenix UV Index with Other United States Cities

The table above highlights how UV exposure in Phoenix compares to other major locations across United States. This comparison helps travelers and residents better understand regional sun intensity and plan outdoor activities with sun safety in mind.

Phoenix's solar exposure compared to other cities in United States. Generated using Copernicus Atmosphere Monitoring Service information.
	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Chicago UVI	3	4	6	8	9	10	10	9	8	6	4	2
Brooklyn UVI	3	5	6	8	10	10	9	9	8	6	4	2
New York City UVI	3	5	6	8	10	10	9	9	8	6	4	2
Los Angeles UVI	4	6	8	9	10	11	11	10	10	7	5	4
Phoenix	4	6	9	10	11	12	11	11	10	7	5	4
Houston UVI	5	8	9	11	11	12	12	11	10	9	7	5