UV Index in London, United States

Last updated: May 3, 2025

Understanding the UV Index is crucial for residents of London, United States, as it serves as a vital indicator of sun exposure risks that can lead to sunburn and long-term skin health issues. With the city’s BSk climate offering a mix of cool winters and warm summers, UV levels can fluctuate significantly throughout the day, peaking at a noteworthy 10 around midday. Being aware of these fluctuations enables residents to take necessary precautions to protect their skin and enjoy the outdoors safely, especially during the sunniest hours. Stay informed and safeguard your health by understanding the UV Index in your area!

Hourly UV Index in London

As the sun rises, the UV Index gradually climbs, starting at a modest 1 at 7:00 AM and reaching an energetic 2 by 8:00 AM. The intensity escalates quickly, peaking at a robust 10 between 12:00 PM and 1:00 PM—the ideal time to take extra sun safety precautions! By 2:00 PM, the index begins its gentle decline, settling to 9 at 2:00 PM, and gradually tapering off to a more manageable 3 by 5:00 PM. As evening approaches, the index dwindles to 1 by 6:00 PM, allowing for a calm end to the day. Remember, during peak hours, it’s crucial to protect your skin to enjoy the sunshine safely!

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	10	very high	15 min
14:00	9	very high	15 min
15:00	7	high	25 min
16:00	5	moderate	30 min
17:00	3	moderate	30 min
18:00	1	low	45 min
19:00	1	low	45 min

Monthly UV Index Trends in London

Throughout the year, the UV Index experiences notable fluctuations, with peak levels occurring in the summer months. March through August sees particularly high readings, with the highest index of 11 observed in June and July, indicating extreme exposure risk and a quick burn time of just 10 minutes. Consequently, these months are considered high-risk for UV exposure, necessitating diligent sun protection measures. Residents and visitors are advised to minimize sun exposure during midday hours, wear protective clothing, and use broad-spectrum sunscreen to safeguard against potential skin damage. As the year progresses, the UV Index generally decreases, reaching lower levels in the fall and winter, with January through February representing a period of moderate exposure.

Monthly Maximum UV Index for London, United States

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

The table above highlights how UV exposure in London 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.

London'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
London	4	5	8	9	10	11	11	10	9	7	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