San Francisco UV Index Today
- Current UV Index0.0
- Cloud Cover00%
- Temperature00.0 ℃
Day Summary
- Max UV Index7.9
- Avg Clouds90%
- Max Temp18.8 ℃
- Peak UV at 1 PM
- Protection Required ☀️
The UV index in San Francisco, United States 
will reach a high of 7.9 today. This means a high level of sun exposure. See our tips below to stay safe!
Last checked: 2025-09-04
Hourly Forecast Chart
Today's Safety Tips
Be careful! The sun's rays are strong. Try to stay in the shade between 10 a.m. and 4 p.m. Wear a hat, sunglasses, and reapply SPF 30+ sunscreen every 2 hours.
San Francisco's UV Index
San Francisco's UV index is typically low to moderate, often ranging from 1 to 6, with higher values in summer months. The city's coastal fog often reduces direct sunlight, keeping UV levels lower than inland areas.
Weather Seasons
The weather in San Francisco features mild, wet winters and cool, dry summers. Fog is common in summer, especially in the mornings, caused by the cold Pacific Ocean meeting warmer air. Rainfall mainly occurs from November through March.
San Francisco's Climate
Compared to other parts of California, San Francisco is cooler and less sunny. Neighboring cities like Oakland or San Jose have warmer summers and less fog. Its coastal location keeps temperatures stable, unlike inland areas with hot summers and cold winters.
Hourly UV Index Trend
See the UV index hour by hour for San Francisco. When the level is high, it's smart to find some shade.
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