UV Index for Napa, CA

Current Napa UV Index

0 (Low)

Last Updated 34 minutes ago

Hourly Napa UV Index

The hourly Napa, CA UV Index forecast for Sunday, August 31st, 2025.

5 Day Hourly Napa UV Index Forecast

Last Updated 14 hours ago

The UV index forecast for the next five days in Napa, CA has no days reaching the extreme level and 3 days reaching the high or very high levels. The peak UV intensity in Napa over the next five days will be 8 on Sunday, August 31st at 1:00 pm.

The UV index forecast for Sunday, August 31st in Napa, 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 0.5
Low
9am 1.5
Low
10am 3.3
Moderate
11am 5.4
Moderate
12pm 7.2
High
1pm 8
Very High
2pm 7.6
High
3pm 6.1
High
4pm 4
Moderate
5pm 2
Low
6pm 0.7
Low
7pm 0.2
Low
8pm 0
Low
9pm 0
Low
10pm 0
Low
11pm 0
Low

The UV index forecast for Monday, September 1st in Napa, 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 0.4
Low
9am 1.4
Low
10am 3.1
Moderate
11am 5.1
Moderate
12pm 6.7
High
1pm 7.5
High
2pm 7.1
High
3pm 5.6
Moderate
4pm 3.7
Moderate
5pm 1.8
Low
6pm 0.7
Low
7pm 0.1
Low
8pm 0
Low
9pm 0
Low
10pm 0
Low
11pm 0
Low

The UV index forecast for Tuesday, September 2nd in Napa, 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 0.4
Low
9am 1.5
Low
10am 3.2
Moderate
11am 5.2
Moderate
12pm 6.9
High
1pm 7.6
High
2pm 7.2
High
3pm 5.8
Moderate
4pm 3.8
Moderate
5pm 1.9
Low
6pm 0.7
Low
7pm 0.1
Low
8pm 0
Low
9pm 0
Low
10pm 0
Low
11pm 0
Low

The UV index forecast for Wednesday, September 3rd in Napa, 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