UV Index for Portola Valley, CA

Current Portola Valley UV Index

1.6 (Low)

Last Updated 24 minutes ago

Hourly Portola Valley UV Index

The hourly Portola Valley, CA UV Index forecast for Thursday, December 4th, 2025.

5 Day Hourly Portola Valley UV Index Forecast

Last Updated 4 hours ago

The UV index forecast for the next five days in Portola Valley, CA has no days reaching the extreme level and no days reaching the high or very high levels. The peak UV intensity in Portola Valley over the next five days will be 2.5 on Friday, December 5th at 12:00 pm.

The UV index forecast for Thursday, December 4th in Portola Valley, CA is below.

Time UV Index Risk
3pm 0.8
Low
4pm 0.2
Low
5pm 0
Low
6pm 0
Low
7pm 0
Low
8pm 0
Low
9pm 0
Low
10pm 0
Low
11pm 0
Low

The UV index forecast for Friday, December 5th in Portola Valley, 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 0.6
Low
10am 1.4
Low
11am 2.1
Low
12pm 2.5
Low
1pm 2.3
Low
2pm 1.6
Low
3pm 0.8
Low
4pm 0.3
Low
5pm 0
Low
6pm 0
Low
7pm 0
Low
8pm 0
Low
9pm 0
Low
10pm 0
Low
11pm 0
Low

The UV index forecast for Saturday, December 6th in Portola Valley, 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 0.5
Low
10am 1
Low
11am 1.2
Low
12pm 1.7
Low
1pm 1.4
Low
2pm 1
Low
3pm 0.6
Low
4pm 0.2
Low
5pm 0
Low
6pm 0
Low
7pm 0
Low
8pm 0
Low
9pm 0
Low
10pm 0
Low
11pm 0
Low

The UV index forecast for Sunday, December 7th in Portola Valley, 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 0.6
Low
10am 1.2
Low
11am 1.9
Low
12pm 2.2
Low
1pm 2
Low
2pm 1.4
Low
3pm 0.7
Low
4pm 0.2
Low
5pm 0
Low
6pm 0
Low
7pm 0
Low
8pm 0
Low
9pm 0
Low
10pm 0
Low
11pm 0
Low

The UV index forecast for Monday, December 8th in Portola Valley, CA is below.

Time UV Index Risk
12am 0
Low
1am 0
Low
2am 0
Low
3am 0
Low
4am 0
Low