UV Index Today in Irvine, California

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.

Irvine's UV Climate

Irvine spreads across the coastal plain of central Orange County, close enough to the Pacific to catch morning marine layer but far enough inland that afternoons run clear and bright. The master-planned city is laced with open greenbelts, bike trails, and sports parks — inviting outdoor spaces with young trees and limited mature shade — and its large university and youth-sports populations spend long weekend hours under strong Southern California sun.

Average Annual UV Index

7.4

Peak UV Season

April - October

Sunny Days per Year

281

Typical UV Index by Season in Irvine

Season Typical Midday UV Protection Needed
Summer Very High (8-10) SPF 30+, hat, sunglasses; shade from 10 AM – 4 PM
Spring & Fall High (6-8) SPF 30+ for extended time outdoors
Winter Moderate (3-5) 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 Orange County:

UV and Weather in Orange County

Learn about Orange 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

Irvine's Mediterranean climate delivers very high summer UV, with midday readings of 8-10 from May through September once the morning clouds burn off. The marine layer pattern creates a specific trap: gray mornings convince people the day is mild, then skies clear right as UV approaches its peak. Fall stays warm and clear through October, extending the high-exposure season well past summer.

UV Index and Health Impact

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

  • Summer: Very High (8-10)
  • Spring/Fall: High (6-8)
  • 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

May and June bring the region's famous morning gloom, which typically dissolves by late morning — leaving the actual peak UV hours fully exposed despite the day's overcast start. Santa Ana wind events in fall produce Irvine's clearest, most brilliant days, with UV noticeably crisp for the season. Winter days are mild and frequently sunny, keeping midday UV in the moderate range for soccer tournaments and trail runs.

Frequently Asked Questions About UV in Irvine

What is the UV index in Irvine today?

The live UV index for Irvine, CA 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 Irvine?

UV radiation is strongest between 10 AM and 4 PM. Irvine's peak UV season runs April - October, when the midday index typically reaches Very High (8-10).

How high does the UV index get in Irvine?

Summer days in Irvine typically reach Very High (8-10). Spring and fall usually bring High (6-8), while winter values are typically Moderate (3-5).

Do I need sunscreen in Irvine during winter?

Yes. Irvine's winter days are often clear with moderate midday UV — enough to matter for weekend sports and long outdoor time.

How sunny is Irvine compared to other cities?

Irvine averages about 281 sunny days per year with an average annual UV index around 7.4.