UV Index in Houston, United States

Last updated: July 2, 2025

Understanding the UV Index is crucial for residents of Houston, Texas, where the sun's rays can be intense, especially during peak hours. With a typical climate characterized by hot, humid summers, awareness of UV levels is essential to prevent sunburn and protect your skin health. In Houston, the UV Index can soar to dangerous levels, peaking at 11 around noon, which highlights the importance of taking appropriate precautions. By tuning into the UV Index, you empower yourself to enjoy the outdoors safely while minimizing the risks associated with overexposure to ultraviolet radiation.

Hourly UV Index in Houston

Expect a sunny day with a fluctuating UV Index that peaks at 11 around midday. The morning starts off gentle, with values rising from 1 at 7:00 AM to 4 by 9:00 AM. As the sun climbs higher, the UV Index escalates sharply, reaching 9 by 11:00 AM and hitting its highest point of 11 at both 12:00 PM and 1:00 PM. After the sun’s zenith, the UV levels gradually decline, dropping to 10 at 2:00 PM and tapering off to 1 by 7:00 PM. Remember to protect your skin during those peak hours for a safe and enjoyable day outdoors!

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
09:004moderate30 min
10:006high25 min
11:009very high15 min
12:0011extreme10 min
13:0011extreme10 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 Houston

Throughout the year, UV Index levels exhibit significant seasonal variations, with high-risk months highlighted between March and August. During this period, the UV Index often reaches very high to extreme levels, particularly in May, June, and July, where it peaks at 11 and suggests a burn time of as little as 10 minutes. Visitors and residents are advised to take precautionary measures, such as wearing sunscreen, protective clothing, and seeking shade during peak hours. In contrast, the lower UV levels in January, December, and November present a moderate risk, with recommended exposure times of 30 and 25 minutes. As the year progresses, it’s crucial to stay informed about these UV changes and adjust sun safety practices accordingly.

Monthly Maximum UV Index for Houston, United States

The monthly maximum UV Index (UVI) represents the highest UV radiation level recorded each month in Houston. It measures the strength of ultraviolet radiation from the sun and helps assess the risk of sunburn and UV-related health issues.
JanFebMarAprMayJunJulAugSepOctNovDec47810111111109764
Data source: Statistical UV Index data for Houston, 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 Houston UV Index with Other United States Cities

The table above highlights how UV exposure in Houston 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.
Houston'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
Los Angeles UVI46891011111010754
Houston47810111111109764
Houston UVI589111112121110975