UV Index Today in Houston, Texas
Houston's UV Climate
Houston, located in southeastern Texas, experiences a humid subtropical climate with high UV exposure throughout the year. The city's southern location, coastal proximity, and generally humid conditions result in strong UV radiation, particularly during the long summer months. The combination of hot weather, outdoor activities, and year-round sunshine makes comprehensive sun protection essential for residents and visitors, especially during outdoor recreation and coastal activities.
Average Annual UV Index
7.8
Peak UV Season
March - October
Sunny Days per Year
204
Typical UV Index by Season in Houston
| Season | Typical Midday UV | Protection Needed |
|---|---|---|
| Summer | Very High to Extreme (9-11) | SPF 30+, hat, sunglasses; shade from 10 AM – 4 PM |
| Spring & Fall | High (6-9) | SPF 30+ for extended time outdoors |
| Winter | Moderate (3-5) | Sunscreen for long midday exposure; more on snow |
UV Index in Nearby Cities
- UV Index in Austin, TX146 mi away
- UV Index in San Antonio, TX189 mi away
- UV Index in Dallas, TX225 mi away
- UV Index in Fort Worth, TX237 mi away
Practical Tips for Outdoor Activities
Make the most of outdoor activities while staying safe in Harris County:
- Check UV index and weather radar before planning outdoor activities
- Schedule outdoor activities during low UV hours
- Use appropriate sun protection based on UV levels
- Stay hydrated during outdoor activities
- Take regular breaks in shaded areas
- Monitor weather conditions for changes
- Be prepared for sudden weather changes
- Know the signs of heat-related illness
- Wear a hat and protective clothing
- Check visibility conditions before outdoor plans
- Stay alert to weather alerts and warnings
UV and Weather in Harris County
Learn about Harris County's unique climate patterns, UV radiation levels, and how they affect your daily life. Enter your zip code for location-specific weather radar data and UV forecasts to help you make informed decisions about outdoor activities and sun protection.
Climate and UV Patterns
Houston's humid subtropical climate creates significant UV exposure patterns with high to very high UV levels for most of the year. The city receives strong UV radiation due to its southern latitude and coastal location, with UV index values frequently reaching 8-9 during peak hours. Local weather radar shows that while humidity can create cloud cover, clear days present maximum UV exposure. The coastal location means UV radiation is more intense than inland areas due to less atmospheric filtering.
UV Index and Health Impact
Understanding UV radiation levels is crucial for protecting your health. Typical clear-day UV index values in Houston through the year:
- Summer: Very High to Extreme (9-11)
- Spring/Fall: High (6-9)
- Winter: Moderate (3-5)
- Peak UV hours: 10 AM - 4 PM
- Cloud cover can reduce UV by 20-40%, but does not eliminate it
- Clear skies bring maximum UV exposure
Local Weather Patterns
Houston's weather patterns create unique UV exposure challenges throughout the year. The city experiences hot, humid summers with frequent clear skies and high UV exposure. Spring and fall bring milder temperatures but still feature high UV levels due to southern latitude. Winter months bring cooler temperatures but still feature moderate to high UV levels due to clear skies. The city's coastal location means sea breezes provide some relief from heat but don't reduce UV radiation.
Frequently Asked Questions About UV in Houston
What is the UV index in Houston today?
The live UV index for Houston, TX is shown at the top of this page and updates throughout the day, along with today's maximum and an hourly forecast.
When is the sun strongest in Houston?
UV radiation is strongest between 10 AM and 4 PM. Houston's peak UV season runs March - October, when the midday index typically reaches Very High to Extreme (9-11).
How high does the UV index get in Houston?
Summer days in Houston typically reach Very High to Extreme (9-11). Spring and fall usually bring High (6-9), while winter values are typically Moderate (3-5).
Do I need sunscreen in Houston during winter?
It is a good idea. Winter UV in Houston still reaches moderate levels on clear days, so sunscreen is recommended for extended time outdoors.
How sunny is Houston compared to other cities?
Houston averages about 204 sunny days per year with an average annual UV index around 7.8.