UV Index in Fairfax, United States

Last updated: May 3, 2025

Understanding the UV Index is crucial for the residents of Fairfax, United States, as it plays a significant role in protecting your skin from harmful sun exposure. With peak UV levels reaching up to 10 during midday, awareness of these numbers can help you prevent sunburn and long-term skin damage. Situated in a Csb climate zone, Fairfax experiences a mix of coastal and continental influences, leading to moderate UV exposure risks throughout the year. By staying informed about local UV levels, you can make smarter choices for sun safety and maintain better skin health.

Hourly UV Index in Fairfax

As the sun rises, the UV Index begins its gradual ascent, starting at a mild 1 at 07:00. By 08:00, it reaches 2, indicating a low risk, perfect for morning strolls. The intensity picks up at 09:00, hitting 3, and then surges to 6 by 10:00. From 11:00 to 13:00, the index escalates dramatically, peaking at an intense 10, marking the hours when sun protection is crucial. The afternoon maintains this peak, with 10 persisting until 14:00. As the day progresses, the evening brings relief; the index drops to 8 at 15:00, and gradually declines to 3 by 17:00, and finally retreats to 1 by 19:00. This hourly data highlights the importance of seeking shade and using sunscreen during midday hours to ensure safety under the sun.

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
13:0010very high15 min
14:0010very high15 min
15:008very high15 min
16:006high25 min
17:003moderate30 min
18:002low45 min
19:001low45 min

Monthly UV Index Trends in Fairfax

The UV Index exhibits significant seasonal variation, peaking during the summer months and dramatically declining in winter. From January to February, the UV Index ranges from 3 to 5, classified as moderate, allowing for around 30 minutes of safe sun exposure. However, March to June sees a sharp increase, reaching an extreme level of 11 in both June and July, where unprotected skin can burn in just 10 minutes. The high-risk months for UV exposure are therefore March through August, where the index remains predominantly high to extreme. As a result, it is crucial for visitors and residents to take protective measures during these months, such as wearing sunscreen, protective clothing, and seeking shade, especially during peak hours. From September to December, while the UV Index decreases, users should still remain vigilant, as moderate levels persist late in the year.

Monthly Maximum UV Index for Fairfax, United States

The monthly maximum UV Index (UVI) represents the highest UV radiation level recorded each month in Fairfax. It measures the strength of ultraviolet radiation from the sun and helps assess the risk of sunburn and UV-related health issues.
JanFebMarAprMayJunJulAugSepOctNovDec3589101111109643
Data source: Statistical UV Index data for Fairfax, 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 Fairfax UV Index with Other United States Cities

The table above highlights how UV exposure in Fairfax 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.
Fairfax'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
Fairfax3589101111109643
Los Angeles UVI46891011111010754
Houston UVI589111112121110975