UV Index in Williston, United States

Last updated: June 2, 2025

Staying aware of the UV Index is crucial for residents of Williston, United States, where sunny days can often lead to increased risk of harmful UV exposure. Understanding UV levels is essential for protecting your skin and preventing sunburn, which can contribute to long-term health issues. With a Cfa climate, Williston experiences a mix of sunny and cloudy days, leading to variable UV exposure; for instance, peak UV levels here can reach a high of 11 around noon. By monitoring the UV Index daily, you can enjoy the outdoors while safeguarding your skin's health.

Hourly UV Index in Williston

The UV Index for the day showcases a dramatic increase in intensity as the sun climbs higher in the sky. Starting at a mild 1 at 07:00, it remains low throughout the morning, only reaching 3 by 09:00. However, by 11:00, the index skyrockets to 8, peaking at an intense 11 from 13:00 to 14:00. As the afternoon wanes, the UV levels gradually decrease, dropping to 4 by 17:00 and tapering off to 1 once again by 19:00. It's clear that midday hours pose the greatest risk for sun exposure, making it crucial to take precautions during the peak hours from 11:00 to 14:00.

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	1	low	45 min
09:00	3	moderate	30 min
10:00	5	moderate	30 min
11:00	8	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	10	very high	15 min
16:00	7	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 Williston

Throughout the year, UV Index levels fluctuate significantly, reflecting varying sun exposure risks. High-risk months include February through August, where the UV Index reaches extreme levels of 11, demanding vigilance from visitors and residents alike, with a burn time of just 10 minutes. March and April also present notable risks, with an Index of 9 and 11 respectively, while September and October continue to show high levels of UV exposure. Winter months of January, November, and December lower the risk, with a moderate level of UV Index, allowing for safer outdoor activities. It is advisable for everyone to apply sunscreen, wear protective clothing, and seek shade during peak sunlight hours, particularly from late winter through summer.

Monthly Maximum UV Index for Williston, United States

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

The table above highlights how UV exposure in Williston 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.

Williston'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
Williston	5	8	9	11	11	11	11	11	10	9	7	5
Houston UVI	5	8	9	11	11	12	12	11	10	9	7	5