UV Index in Tempe, United States

Last updated: June 2, 2025

Understanding the UV Index is essential for residents of Tempe, Arizona, where the climate is characterized by hot, arid conditions typical of a BWh zone. With maximum UV levels peaking at 12 during midday hours, awareness of this index can be the key to preventing sunburn and promoting long-term skin health. Given Tempe's abundant sunshine, knowing when UV exposure is highest can help you take proactive measures against harmful effects, ensuring you enjoy the great outdoors safely.

Hourly UV Index in Tempe

The UV Index throughout the day reveals a notable peak of intensity around midday. Starting from a gentle 1 at 07:00, the index rises gradually to reach 3 by 08:00. As the sun climbs higher, things heat up quickly, with values soaring to 5 at 09:00 and then sharply escalating to a maximum of 12 by 12:00. This potent level of UV exposure is sustained until 13:00, when it slightly dips to 11. The afternoon brings a gradual decline, with readings of 10 at 14:00, 7 at 15:00, and slipping further to 5 at 16:00. As the sun begins to set, the UV Index dwindles back down to 2 at 17:00 and settles at a safer 1 by 18:00 and 19:00. It's a clear reminder to protect your skin during those peak hours!

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	12	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	2	low	45 min
18:00	1	low	45 min
19:00	1	low	45 min

Monthly UV Index Trends in Tempe

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 Tempe, United States

The monthly maximum UV Index (UVI) represents the highest UV radiation level recorded each month in Tempe. 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 Tempe, 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 Tempe UV Index with Other United States Cities

The table above highlights how UV exposure in Tempe 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.

Tempe'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
Tempe	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