As of 2:33 AM PDT on July 13, 2025, all 20 cities in Alameda County, CA in our database have a UV Index reading of 0, indicating no radiation from the sun.
Over the next 24 hours, the highest UV Index reading in Alameda County, CA is expected to be 10.9 in Hayward between 1:00 PM - 2:00 PM PDT today.
| Range | 0 - 2 | 3 - 5 | 6 - 7 | 8 - 10 | 11+ |
|---|---|---|---|---|---|
| Color | |||||
| Risk | Low | Moderate | High | Very High | Extreme |