San Mateo County, CA: Current UV Index and Hourly Forecast

As of 10:30 PM PDT on August 1, 2025, all 33 cities in San Mateo 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 San Mateo County, CA is expected to be 10.8 in Portola Valley between 1:00 PM - 2:00 PM PDT tomorrow.

Search Cities in San Mateo County, CA

UV Index Risk Levels
Range0 - 23 - 56 - 78 - 1011+
Color
RiskLowModerateHighVery HighExtreme
UV Index in San Mateo County, CA as of 10:30 PM PDT, August 1, 2025

Current UV Index in Cities in San Mateo County, CA

10:30 PM PDT, August 1, 2025