UV Index Today in Santa Clara, 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.

Santa Clara's UV Climate

Santa Clara sits in the flat heart of Silicon Valley, shielded from Pacific fog by the Santa Cruz Mountains and blessed — or cursed — with over 260 sunny days a year. Daytime life here happens outdoors more than people realize: campus courtyards and lunchtime walking loops, youth sports complexes, Levi's Stadium's famously sun-exposed eastern seating, and California's Great America all put people under a strong valley sun through the long dry season.

Average Annual UV Index

7.0

Peak UV Season

April - October

Sunny Days per Year

260

Typical UV Index by Season in Santa Clara

Season Typical Midday UV Protection Needed
Summer Very High (8-10) SPF 30+, hat, sunglasses; shade from 10 AM – 4 PM
Spring & Fall Moderate to High (5-8) SPF 30+ for extended time outdoors
Winter Low to Moderate (2-4) 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 Santa Clara County:

UV and Weather in Santa Clara County

Learn about Santa Clara 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

Santa Clara's Mediterranean climate delivers dry, warm, dependably clear weather from April through October, with summer midday UV index values of 8-10. The valley position means less marine cloud than coastal cities — morning overcast is thinner and burns off earlier, leaving most peak UV windows fully exposed. Winters are mild, with sunny days between rain systems reaching low-moderate midday UV.

UV Index and Health Impact

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

  • Summer: Very High (8-10)
  • Spring/Fall: Moderate to High (5-8)
  • Winter: Low to Moderate (2-4)
  • 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

The dry season's weather is remarkably consistent — clear mornings, warm afternoons, cool evenings — which builds outdoor routines that run for months without a cloudy break. Afternoon stadium events are a known roast: the sun angle late in the day hits east-facing seats for hours. Winter alternates Pacific storm systems with bright, crisp stretches that keep runners and cyclists exposed to meaningful midday UV year-round.

Frequently Asked Questions About UV in Santa Clara

What is the UV index in Santa Clara today?

The live UV index for Santa Clara, 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 Santa Clara?

UV radiation is strongest between 10 AM and 4 PM. Santa Clara'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 Santa Clara?

Summer days in Santa Clara typically reach Very High (8-10). Spring and fall usually bring Moderate to High (5-8), while winter values are typically Low to Moderate (2-4).

Do I need sunscreen in Santa Clara during winter?

Clear winter days in Santa Clara reach low-moderate midday UV; sunscreen makes sense for long outdoor sessions even in the cool months.

How sunny is Santa Clara compared to other cities?

Santa Clara averages about 260 sunny days per year with an average annual UV index around 7.0.