When is UV highest today in San Mateo, CA
UV Index
High
Today's UV index is high. If working or spending time outdoors, wear UV protective clothing, use sunscreen, and try to avoid direct sun exposure between 11 AM and 4 PM.
TodayTomorrow
ExtremeVery highHighModerateLow
8PM
11PM
2AM
5AM
LowModerateHigh
Hourly UV and cloud cover
UV index is unitless. Cloud cover is shown as a percentage.
HourUV indexCloud cover
9PM7High17%
10PM6High18%
11PM5Moderate18%
12AM4Moderate16%
1AM3Moderate16%
2AM2Low20%
3AM0Low23%
4AM0Low25%
5AM0Low27%
6AM0Low29%