UV Index in Sonoma, United States

Last updated: June 2, 2025

In Sonoma, understanding the UV Index is crucial for protecting your skin from harmful ultraviolet radiation. With UV levels peaking at 11 during midday hours, being aware of these values can significantly aid in sunburn prevention and overall skin health. The Mediterranean climate of Sonoma, characterized by warm summers and mild winters, brings specific UV exposure risks, making it essential for residents and visitors alike to stay informed. By keeping an eye on the UV Index, you can enjoy the beautiful California sunshine while minimizing the potential damage to your skin.

Hourly UV Index in Sonoma

As the sun rises, the UV Index begins its ascent, starting at a mild 1 at 07:00. By 08:00, it gently climbs to 2, but watch out as it rampages up to 4 by 09:00. The real intensity kicks in at 10:00, when the index hits a 6, and it reaches its peak of 10 at 12:00. The sun is relentless, pushing the index to 11 from 13:00 to 14:00, making this the most hazardous time of the day. Fortunately, the UV levels start to decline after 15:00, dropping back to 9, then dwindling to 4 by 17:00, and finally retreating to a safer 1 by 19:00. Ensure you take proper sun protection measures during the peak hours to safeguard your skin!

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	9	very high	15 min
12:00	10	very high	15 min
13:00	11	extreme	10 min
14:00	11	extreme	10 min
15:00	9	very high	15 min
16:00	6	high	25 min
17:00	4	moderate	30 min
18:00	2	low	45 min
19:00	1	low	45 min

Monthly UV Index Trends in Sonoma

Throughout the year, UV exposure varies significantly, with high-risk months typically occurring from March to September. During these months, particularly in April through July, the UV index reaches notably high levels, peaking at 11, which indicates extreme exposure risks and a quick burn time of just 10 minutes. As the seasons shift, visitors and residents should be particularly vigilant from May to August, when protective measures such as sunscreen, hats, and seeking shade are essential to prevent skin damage. In contrast, January, November, and December present a moderate UV index of 3-4, allowing for longer burn times of 30 minutes, though sunscreen should still be applied. Staying informed about these UV changes can help ensure safe outdoor activities year-round.

Monthly Maximum UV Index for Sonoma, United States

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

The table above highlights how UV exposure in Sonoma 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.

Sonoma'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
Sonoma	3	5	7	9	10	11	11	10	9	6	4	3
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