UV Index in Walnut, United States

Last updated: July 2, 2025

Understanding the UV Index is crucial for residents of Walnut, United States, where sunny days can lead to elevated UV levels that pose risks to skin health. With readings peaking at 10 during midday hours, it's essential to stay informed to prevent activities that could result in painful sunburns. In Walnut's Dfa climate, where summer sun can be strong, monitoring the UV Index helps safeguard against long-term skin damage and encourages safe sun practices. Keep your skin protected and enjoy the sun sensibly!

Hourly UV Index in Walnut

The UV index on this particular day presents a notable trend as the sun rises and peaks. Starting at 07:00, the index is a gentle 1, gradually climbing to 2 by 08:00. The ascent continues as it reaches 4 at 09:00 and hits 6 by 10:00. Midday shines brightest, with the index soaring to a maximum of 10 at both 12:00 and 13:00, indicating a high potential for skin damage without protection. As the day progresses, values begin to dip, falling to 9 at 14:00, and then decreasing further to 8 at 15:00. By 16:00, the UV index drops to 6, and as evening approaches, it relaxes to 3 at 17:00, down to 2 by 18:00, and finally retreating to 1 at 19:00. It's a day that emphasizes the importance of sun protection during the 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	2	low	45 min
09:00	4	moderate	30 min
10:00	6	high	25 min
11:00	8	very high	15 min
12:00	10	very high	15 min
13:00	10	very high	15 min
14:00	9	very high	15 min
15:00	8	very high	15 min
16:00	6	high	25 min
17:00	3	moderate	30 min
18:00	2	low	45 min
19:00	1	low	45 min

Monthly UV Index Trends in Walnut

Throughout the year, the UV Index experiences notable fluctuations, with the highest risk months occurring from March to September, when the index consistently ranges between 6 and 10. Specifically, April to August feature very high levels, with peak values reaching 10 in June and July, corresponding to a dangerously short burn time of 15 minutes. In contrast, January and December present lower UV risks, categorized as moderate to low, with corresponding burn times of 30 minutes and 45 minutes, respectively. To safeguard your skin, it is crucial for visitors and residents to adopt protective measures, especially during the peak months by using sunscreen, wearing protective clothing, and seeking shade during midday hours to reduce UV exposure effectively.

Monthly Maximum UV Index for Walnut, United States

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

The table above highlights how UV exposure in Walnut 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.

Walnut'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
Walnut	3	5	6	8	9	10	10	9	8	6	4	2
Los Angeles UVI	4	6	8	9	10	11	11	10	10	7	5	4
Houston UVI	5	8	9	11	11	12	12	11	10	9	7	5