UV Index in Lancaster, United States

Last updated: June 2, 2025

Understanding the UV Index in Lancaster, United States is crucial for safeguarding your skin and overall health. With the potential for sunburn and long-term skin damage on the rise during sunny days, being aware of UV levels helps you make informed decisions about sun exposure. Lancaster, with its Dfa climate, experiences significant UV radiation, especially during peak hours around noon, where the index can soar to 11. By staying informed about UV risks, you can enjoy the sunny outdoors while effectively protecting yourself from harmful UV rays.

Hourly UV Index in Lancaster

The UV Index throughout the day follows a predictable rise and fall, peaking at 11 around 1:00 PM. Starting at a modest 1 at 7:00 AM, it gradually escalates, reaching 10 by 12:00 PM, signaling the need for sun protection. As the afternoon progresses, the index dips from 11 to 8 by 3:00 PM, then declines further to 2 by 6:00 PM, and finally settles back at 1 by 7:00 PM. This data underscores the importance of taking precautions during the hours of peak UV exposure, particularly between 11:00 AM and 3:00 PM, when levels are highest and pose the greatest risk to skin health.

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	11	extreme	10 min
14:00	10	very high	15 min
15:00	8	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 Lancaster

Throughout the year, the UV Index exhibits significant seasonal variations, with high-risk months occurring from April to August. During this period, the UV Index peaks at 11, categorized as extreme in June and July, meaning visitors and residents should take extra precautions. Notably, April and May also pose high risks with very high ratings of 9 and 10, respectively. As a guideline, those spending time outdoors should limit sun exposure during these months, particularly between 10 AM and 4 PM, when UV rays are most intense. It’s advisable to wear protective clothing, apply broad-spectrum sunscreen, and seek shade to minimize the risk of skin damage. As we transition into the fall and winter months, UV levels decrease, with December presenting a much lower risk. However, even in moderate months like January and February, some sun protection remains necessary for prolonged outdoor activities.

Monthly Maximum UV Index for Lancaster, United States

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

The table above highlights how UV exposure in Lancaster 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.

Lancaster'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
Lancaster	3	5	6	9	10	11	11	10	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