UV Index for San Francisco, CA

Current San Francisco UV Index

0 (Low)

Last Updated 26 minutes ago

Hourly San Francisco UV Index

The hourly San Francisco, CA UV Index forecast for Tuesday, September 16th, 2025.

5 Day Hourly San Francisco UV Index Forecast

Last Updated 14 hours ago

The UV index forecast for the next five days in San Francisco, CA has no days reaching the extreme level and 2 days reaching the high or very high levels. The peak UV intensity in San Francisco over the next five days will be 7.3 on Tuesday, September 16th at 1:00 pm.

The UV index forecast for Tuesday, September 16th in San Francisco, CA is below.

Time UV Index Risk
2am 0
Low
3am 0
Low
4am 0
Low
5am 0
Low
6am 0
Low
7am 0
Low
8am 0.3
Low
9am 1.2
Low
10am 2.8
Low
11am 4.8
Moderate
12pm 6.5
High
1pm 7.3
High
2pm 6.6
High
3pm 5.2
Moderate
4pm 3.4
Moderate
5pm 1.6
Low
6pm 0.5
Low
7pm 0
Low
8pm 0
Low
9pm 0
Low
10pm 0
Low
11pm 0
Low

The UV index forecast for Wednesday, September 17th in San Francisco, CA is below.

Time UV Index Risk
12am 0
Low
1am 0
Low
2am 0
Low
3am 0
Low
4am 0
Low
5am 0
Low
6am 0
Low
7am 0
Low
8am 0.3
Low
9am 1.2
Low
10am 2.9
Low
11am 4.8
Moderate
12pm 6.3
High
1pm 6.7
High
2pm 6.1
High
3pm 4.8
Moderate
4pm 2.8
Low
5pm 1.3
Low
6pm 0.4
Low
7pm 0
Low
8pm 0
Low
9pm 0
Low
10pm 0
Low
11pm 0
Low

The UV index forecast for Thursday, September 18th in San Francisco, CA is below.

Time UV Index Risk
12am 0
Low
1am 0
Low
2am 0
Low
3am 0
Low
4am 0
Low
5am 0
Low
6am 0
Low
7am 0
Low
8am 0.2
Low
9am 0.9
Low
10am 1.8
Low
11am 3.5
Moderate
12pm 4.6
Moderate
1pm 5.2
Moderate
2pm 5.3
Moderate
3pm 2
Low
4pm 1.3
Low
5pm 0.3
Low
6pm 0.1
Low
7pm 0
Low
8pm 0
Low
9pm 0
Low
10pm 0
Low
11pm 0
Low

The UV index forecast for Friday, September 19th in San Francisco, CA is below.

Time UV Index Risk
12am 0
Low
1am 0
Low
2am 0
Low
3am 0
Low
4am 0
Low
5am 0
Low
View Historical UV Index Data