San Francisco UV index in December
Typical ultraviolet levels for San Francisco during December, from the past year of data.
Low
San Francisco
Low UV. You can safely enjoy being outside; the sun's rays are not very strong.
2.1
UV Index
December average
Low
Moderate
High
Very High
Extreme
December UV
2.0742
Risk level
Low
Yearly peak
10.8042
Peak month
July
San Francisco UV index — monthly trend
Average UV index by month over the past year, with December highlighted.
Visiting San Francisco in December?
In December, San Francisco's typical UV index is about 2.0742 — a low risk level. Low UV. You can safely enjoy being outside; the sun's rays are not very strong.
Across the year, San Francisco sees the strongest UV in Summer, peaking around 10.8042 in July. Plan sun protection accordingly.
