UV Index in Williams, United States

Last updated: July 2, 2025

Understanding the UV Index is crucial for residents and visitors in Williams, United States, especially given the area's warm, dry climate. With peak UV levels reaching 11 during midday, awareness of these fluctuations is essential for preventing sunburn and promoting long-term skin health. As Williams often experiences high solar exposure, knowing when to seek shade or apply sunscreen is key to enjoying the region’s beautiful outdoors while minimizing the risk of harmful UV rays. Stay informed to protect yourself and make the most of your time in the sun!

Hourly UV Index in Williams

As the sun rises, the UV Index starts off gently at 1 by 7:00 AM, gradually climbing as the day progresses. By 10:00 AM, it reaches 6, signaling a notable increase in solar radiation. The intensity peaks at 12:00 PM with a striking 10 and continues to soar to a maximum of 11 at 1:00 PM, marking the hour of greatest exposure. As the afternoon unfolds, the index begins to taper off—dropping to 10 at 2:00 PM and 8 by 3:00 PM. By late afternoon, the UV Index gracefully descends to 4 at 5:00 PM, settling back to 2 by 6:00 PM and finally returning to a gentle 1 by 7:00 PM. This highlights the importance of sun protection during mid-day when UV rays are at their most intense.

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.
TimeUVICategoryTime to Burn
07:001low45 min
08:002low45 min
09:003moderate30 min
10:006high25 min
11:008very high15 min
12:0010very high15 min
13:0011extreme10 min
14:0010very high15 min
15:008very high15 min
16:006high25 min
17:004moderate30 min
18:002low45 min
19:001low45 min

Monthly UV Index Trends in Williams

Throughout the year, UV levels exhibit notable seasonal changes, with high-risk months occurring from April to August, where the UV Index reaches extreme levels of 11. Specifically, May, June, and July are critical periods, characterized by minimal burn times of just 10 minutes. In contrast, the winter months of January, February, November, and December display a lower UV Index, categorized as moderate (3-5), allowing up to 30 minutes of sun exposure without significant risk. As UV exposure increases, it is crucial for residents and visitors to take precautions, especially during high-risk months by wearing protective clothing, using sunscreen, and seeking shade during peak hours to effectively mitigate the risks of sunburn and long-term skin damage.

Monthly Maximum UV Index for Williams, United States

The monthly maximum UV Index (UVI) represents the highest UV radiation level recorded each month in Williams. It measures the strength of ultraviolet radiation from the sun and helps assess the risk of sunburn and UV-related health issues.
JanFebMarAprMayJunJulAugSepOctNovDec3578111111109643
Data source: Statistical UV Index data for Williams, 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 Williams UV Index with Other United States Cities

The table above highlights how UV exposure in Williams 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.
Williams's solar exposure compared to other cities in United States. Generated using Copernicus Atmosphere Monitoring Service information.
 JanFebMarAprMayJunJulAugSepOctNovDec
Chicago UVI34689101098642
Brooklyn UVI35681010998642
New York City UVI35681010998642
Williams3578111111109643
Los Angeles UVI46891011111010754
Houston UVI589111112121110975