UV Index Today in Mesa, Arizona

Current UV
Today's Max

Hourly UV Forecast

low moderate high very high extreme

Surface Type

Reflective surfaces increase your UV exposure — snow reflects up to 90%, sand about 20%.

Safe Exposure Time

Estimated burn times based on the Fitzpatrick scale for skin color and today's maximum UV index of . Tap your skin type:

Very fair skin, always burns, never tans

Time until burn
With SPF 15*
With SPF 30*

*Assumes proper application of broad-spectrum sunscreen with reapplication every 2 hours. Estimates follow WHO guidance and satellite-derived data — see how our data works.

Sun Times

Dawn
Sunrise
Solar Noon
Sunset
Dusk
Day Length
Morning Golden Hour Ends
Evening Golden Hour

Important Safety Information

General Guidelines

These exposure times are estimates based on scientific research and should be used as general guidelines only. Individual responses to UV exposure may vary.

Affecting Factors

UV exposure is affected by: time of day, season, altitude, cloud cover, reflection from surfaces, and individual skin sensitivity.

Protection Tips

Seek shade during peak UV hours (10 AM - 4 PM), wear protective clothing, use broad-spectrum sunscreen, and monitor the UV index regularly.

Medical Advice

Consult a healthcare provider for personalized sun protection advice, especially if you have a history of skin conditions or take medications that increase sun sensitivity.

Mesa's UV Climate

Mesa sprawls across the eastern Valley of the Sun, with over 300 sunny days a year and a UV climate that ranks with the harshest in the nation. The city is a spring training hub — Cactus League crowds fill Sloan Park and Hohokam Stadium bleachers through March afternoons of already-high desert UV — and the Salt River lakes, Usery Mountain trails, and winter-visitor golf culture keep exposure constant across seasons that other cities would call off-season.

Average Annual UV Index

9.0

Peak UV Season

April - September

Sunny Days per Year

301

Typical UV Index by Season in Mesa

Season Typical Midday UV Protection Needed
Summer Extreme (10-11+) SPF 30+, hat, sunglasses; shade from 10 AM – 4 PM
Spring & Fall High to Very High (7-10) SPF 30+ for extended time outdoors
Winter Moderate (4-5) Sunscreen for long midday exposure; more on snow

UV Index in Nearby Cities

Practical Tips for Outdoor Activities

Make the most of outdoor activities while staying safe in Maricopa County:

UV and Weather in Maricopa County

Learn about Maricopa 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

Mesa's Sonoran Desert climate delivers extreme summer UV of 11+ for months at a stretch, with essentially no cloud season to interrupt it. Spring — peak visitor season — already runs high to very high, catching March baseball crowds and hikers before summer's heat makes shade non-negotiable. Even December and January hold moderate midday values of 4-5 under routinely cloudless skies.

UV Index and Health Impact

Understanding UV radiation levels is crucial for protecting your health. Typical clear-day UV index values in Mesa through the year:

  • Summer: Extreme (10-11+)
  • Spring/Fall: High to Very High (7-10)
  • Winter: Moderate (4-5)
  • 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

From fall through spring, Mesa's weather is a broken record of clear, dry sunshine — perfect golf and baseball weather that delivers maximum UV penetration day after day. The summer monsoon brings spectacular evening thunderstorms and dust walls, but daytime hours stay largely sun-exposed. Desert dryness evaporates sweat instantly, muting the body's overheating signals that would otherwise pull people out of the sun.

Frequently Asked Questions About UV in Mesa

What is the UV index in Mesa today?

The live UV index for Mesa, AZ 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 Mesa?

UV radiation is strongest between 10 AM and 4 PM. Mesa's peak UV season runs April - September, when the midday index typically reaches Extreme (10-11+).

How high does the UV index get in Mesa?

Summer days in Mesa typically reach Extreme (10-11+). Spring and fall usually bring High to Very High (7-10), while winter values are typically Moderate (4-5).

Do I need sunscreen in Mesa during winter?

Yes. Mesa's winter UV holds moderate levels nearly every day, and golf rounds or spring training afternoons accumulate real exposure — sunscreen is year-round equipment here.

How sunny is Mesa compared to other cities?

Mesa averages about 301 sunny days per year with an average annual UV index around 9.0.