UV Index in Tempe, United States

Last updated: May 3, 2025

In Tempe, United States, understanding the UV Index is crucial for safeguarding your skin against harmful rays. With a desert climate characterized by abundant sunshine and intense UV exposure, awareness of daily UV levels helps prevent sunburn and long-term skin damage. During peak hours, particularly between 10 AM and 2 PM, the UV Index can soar to dangerous levels, reaching as high as 11, making it essential to take protective measures. By staying informed about the UV Index, residents can enjoy the sun safely while prioritizing their skin health.

Hourly UV Index in Tempe

The UV Index throughout the day showcases a remarkable rise, peaking impressively at 11 between noon and 1 PM. Starting with a modest 1 at 7 AM, the index escalates to around 3 by 8 AM and rapidly climbs, hitting 5 by 9 AM. The ascent continues as the sun reaches its zenith, soaring to 8 at 10 AM and breaching the 10 mark by 11 AM. As we reach peak sun hours, it stabilizes at 11 for both 12 PM and 1 PM, before gradually descending to 9 at 2 PM and tapering off to 7 by 3 PM. The latter part of the afternoon sees a gentle decline to 4 at 4 PM, finally returning to the morning's low of 1 by 6 PM, and maintaining this relaxed level through 7 PM. It's a vivid reminder of the sun's strength, urging outdoor enthusiasts to stay sun-smart during the intense midday 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	11	extreme	10 min
13:00	11	extreme	10 min
14:00	9	very high	15 min
15:00	7	high	25 min
16:00	4	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