California UV Index by City
California spans roughly 9 degrees of latitude plus coast, valley, desert and mountains, so UV here is anything but uniform. Pick your city below for a labelled typical hourly reference and a location-aware current-UV check.
There is no single "California UV" number: the index climbs as you move south and inland, peaks midday near the summer solstice, and runs higher at altitude and near reflective water or snow. Southern and inland cities like San Diego, Los Angeles and Fresno tend to hit higher UV than fog-prone San Francisco, and the EPA still flags UV 3+ as a level to protect against. Each linked city page starts with a labelled typical reference and shows current and forecast UV only after a usable response; these are estimates to manage burn risk, not a promise of a safe tan or medical advice.
UV by city in California
Plan from California UV
Source & freshness
Each city page starts with a labelled typical clear-sky reference for California and replaces it only after a usable current UV response. Failed requests remain visibly labelled as reference data. Estimates only — not medical advice.
Questions
Which California city has the highest UV?
Southern and inland cities such as San Diego, Los Angeles and Fresno generally see the highest typical peak UV because of lower latitude, clearer inland skies and summer sun angle, often reaching the EPA "very high" 8+ band on clear summer middays. Coastal fog can briefly lower readings in places like San Francisco, but UV still penetrates haze, so use the current-UV check instead of assuming the coast is always lower. These are estimates, not medical advice.
When is UV lowest in California?
UV is typically lowest in the early morning and late afternoon year-round, and seasonally in the late-fall and winter months when the sun sits lower in the sky. Even then the EPA notes UV 3 or higher can occur on bright winter days, and clouds, altitude, snow and water reflection can change real exposure. Use each city page's labelled reference for orientation and its current forecast after a usable update.
Is it safe to tan in California at midday?
Midday (roughly 10am-4pm) is when UV peaks across California and is often in the EPA high (6-7) or very high (8+) bands, so the WHO advice to protect from UV 3+ applies and burn risk is greatest then. There is no truly "safe" tan, since any tanning is UV damage; if you go out, the FDA recommends broad-spectrum SPF 30+ reapplied every 2 hours and after swimming or sweating, plus shade and clothing. Our tanning-time figures are risk-managed estimates, not medical advice, and your Fitzpatrick skin type, medications and reflective surfaces all change real risk.