San Juan UV index in September
Typical ultraviolet levels for San Juan during September, from the past year of data.
Extreme
San Juan
Extreme UV. Avoid sun exposure, seek shade, and use comprehensive protection: clothing, sunscreen, and a hat.
13.2
UV Index
September average UTC
Low
Moderate
High
Very High
Extreme
September UV
13.1575
Risk level
Extreme
Yearly peak
13.787
Peak month
August
San Juan UV index — monthly trend
Average UV index by month over the past year, with September highlighted.
Visiting San Juan in September?
In September, San Juan's typical UV index is about 13.1575 — a extreme risk level. Extreme UV. Avoid sun exposure, seek shade, and use comprehensive protection: clothing, sunscreen, and a hat.
Across the year, San Juan sees the strongest UV in Summer, peaking around 13.787 in August. Plan sun protection accordingly.
