UV Index in San Jose, California Today

What the UV index means in San Jose

The UV index is a simple 0 to 11+ scale for the strength of the sun's ultraviolet radiation. The higher the number, the faster unprotected skin can burn. In San Jose, like everywhere, the reading rises and falls through the day and shifts with the seasons, cloud cover, and how high the sun sits in the sky.

Use the live reading at the top of this page to decide what you need right now. As a rule of thumb: at UV 3 or above, wear sunscreen and a hat; at UV 6 and above, add shade during the middle of the day; at UV 8 and above, treat midday sun with real caution.

UV in San Jose: geography and seasons

At 37.3° N, San Jose has a clear seasonal swing: UV is high around June and July when the sun rides high in the sky, and much lower in winter when it stays low. San Jose sits near sea level (26 m), so altitude adds little to its UV.

Sources: coordinates and elevation from GeoNames; UV, altitude, and latitude guidance from the World Health Organization and the US EPA.

Sun-safety tips for San Jose

• Check the current UV index above before spending time outdoors.
• Apply broad-spectrum SPF 30+ sunscreen 15 minutes before going out, and reapply every two hours.
• Seek shade between 10 a.m. and 4 p.m., when UV is strongest.
• Wear a wide-brim hat and UV-blocking sunglasses.
• Remember that UV passes through light cloud and reflects off water, sand, and snow.