UV Index for Ontario, CA

Current Ontario UV Index

0 (Low)

Last Updated 45 minutes ago

Hourly Ontario UV Index

The hourly Ontario, CA UV Index forecast for Wednesday, July 2nd, 2025.

5 Day Hourly Ontario UV Index Forecast

Last Updated 12 hours ago

The UV index forecast for the next five days in Ontario, CA has 3 days reaching the extreme level and 1 day reaching the high or very high levels. The peak UV intensity in Ontario over the next five days will be 11.4 on Saturday, July 5th at 1:00 pm.

The UV index forecast for Wednesday, July 2nd in Ontario, CA is below.

Time UV Index Risk

The UV index forecast for Thursday, July 3rd in Ontario, 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 0.4
Low
8am 1.5
Low
9am 3.5
Moderate
10am 6.1
High
11am 8.8
Very High
12pm 10.7
Very High
1pm 11.2
Extreme
2pm 10.3
Very High
3pm 8.2
Very High
4pm 5.4
Moderate
5pm 2.9
Low
6pm 1.2
Low
7pm 0.3
Low
8pm 0
Low
9pm 0
Low
10pm 0
Low
11pm 0
Low

The UV index forecast for Friday, July 4th in Ontario, 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 0.4
Low
8am 1.5
Low
9am 3.4
Moderate
10am 5.9
Moderate
11am 8.4
Very High
12pm 10.4
Very High
1pm 11
Extreme
2pm 10
Very High
3pm 8.1
Very High
4pm 5.4
Moderate
5pm 2.9
Low
6pm 1.2
Low
7pm 0.3
Low
8pm 0
Low
9pm 0
Low
10pm 0
Low
11pm 0
Low

The UV index forecast for Saturday, July 5th in Ontario, 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 0.4
Low
8am 1.6
Low
9am 3.6
Moderate
10am 6.2
High
11am 8.8
Very High
12pm 10.8
Very High
1pm 11.4
Extreme
2pm 10.4
Very High
3pm 8.4
Very High
4pm 5.7
Moderate
5pm 3
Moderate
6pm 1.2
Low
7pm 0.3
Low
8pm 0
Low
9pm 0
Low
10pm 0
Low
11pm 0
Low

The UV index forecast for Sunday, July 6th in Ontario, 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