UV Index in Washington, United States

Last updated: May 3, 2025

Understanding the UV Index is crucial for residents of Washington, United States, where varying weather conditions can lead to unexpected sun exposure. Awareness of UV levels not only helps in preventing painful sunburns but also plays a vital role in maintaining overall skin health. Given Washington's Cfa climate—characterized by warm summers and ample sunshine—it's important to recognize the risks of high UV exposure, especially from late morning to early afternoon when indices peak at levels 11 to 12. Stay informed, protect your skin, and enjoy the beautiful outdoors safely!

Hourly UV Index in Washington

As the sun rises, the UV Index begins its ascent, starting from a gentle 1 at 07:00. By 09:00, it hits 4, signaling a moderate increase. The real ascent occurs from 10:00 onward, peaking at an intense 12 by 13:00, where sun protection becomes essential. This peak is followed by a brief dip, as the index drops to 9 at 15:00, before tapering off towards the evening. As the day comes to a close, UV levels reduce to 3 at 17:00 and settle back to 1 by 19:00, highlighting the critical hours for sun exposure between 11:00 and 14:00. Stay safe and protect your skin during those peak UV times!

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	11	extreme	10 min
13:00	12	extreme	10 min
14:00	11	extreme	10 min
15:00	9	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 Washington

Throughout the year, seasonal UV changes indicate significant fluctuations in sun exposure risk. From January to March, the UV Index rises from moderate (5) to very high (9), with burn times decreasing from 30 to 15 minutes. The high-risk months are April through August, where the UV Index peaks at an extreme level of 12, allowing for a burn time of only 10 minutes. As the year progresses, UV levels gradually decrease, with a return to very high levels in September and October before dropping to a high category in November and moderate levels again in December. Visitors and residents are advised to take precautions during peak months by using sunscreen, wearing protective clothing, and seeking shade, especially between 11 AM and 4 PM when UV rays are the strongest.

Monthly Maximum UV Index for Washington, United States

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

The table above highlights how UV exposure in Washington 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.

Washington'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
Washington	5	8	9	11	11	12	12	12	10	9	6	5
Houston UVI	5	8	9	11	11	12	12	11	10	9	7	5