Walnut, California, United States UV Index Forecast

Find the UV Index forecast for today, tomorrow and the next 15 days for Walnut, California, United States, The Ultraviolet Index forecast, which measures the radiation from the sun that reaches the Earth's surface is updated hourly.

Current UV Index
8:00 am

Low1

UV INDEX

Hourly UV Index Forecast for Today
September 12, 2025

0
7 am
1
8 am
3
9 am
5
10 am
7
11 am
9
12 pm
9
1 pm
9
2 pm
8
3 pm
6
4 pm
4
5 pm
2
6 pm
  • Low
    1-2
  • Moderate
    3-4-5
  • High
    6-7
  • Very High
    8-9-10
  • Xtreme
    11+

As of 8:00 am today in Walnut, California, United States, the UV Index is currently at a Low level of 1.

Summary of Hourly UV Index Forecast for Today and Tomorrow in Walnut, California, United States.

Today

Time Range UV Index Risk
7 am 0
Low
8 am 1
Low
9 am 3
Moderate
10 am 5
Moderate
11 am 7
High
12 pm 9
Very High
1 pm 9
Very High
2 pm 9
Very High
3 pm 8
Very High
4 pm 6
High
5 pm 4
Moderate
6 pm 2
Low

Tomorrow

Time Range UV Index Risk
7 am 0
Low
8 am 1
Low
9 am 2
Low
10 am 4
Moderate
11 am 6
High
12 pm 8
Very High
1 pm 9
Very High
2 pm 9
Very High
3 pm 7
High
4 pm 6
High
5 pm 5
Moderate
6 pm 3
Moderate

Daily Walnut UV Index Forecast for the next 15 days:

9
12 Sep
9
13 Sep
9
14 Sep
9
15 Sep
9
16 Sep
8
17 Sep
8
18 Sep
8
19 Sep
6
20 Sep
8
21 Sep
5
22 Sep
8
23 Sep
8
24 Sep
8
25 Sep
  • Low
    1-2
  • Moderate
    3-4-5
  • High
    6-7
  • Very High
    8-9-10
  • Xtreme
    11+

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