UV Index for Johnston, SC

Current Johnston UV Index

1.4 (Low)

Last Updated 44 minutes ago

Hourly Johnston UV Index

The hourly Johnston, SC UV Index forecast for Tuesday, October 21st, 2025.

5 Day Hourly Johnston UV Index Forecast

Last Updated 20 hours ago

The UV index forecast for the next five days in Johnston, SC has no days reaching the extreme level and no days reaching the high or very high levels. The peak UV intensity in Johnston over the next five days will be 5.4 on Tuesday, October 21st at 1:00 pm.

The UV index forecast for Tuesday, October 21st in Johnston, SC is below.

Time UV Index Risk
11am 2.9
Low
12pm 4.4
Moderate
1pm 5.4
Moderate
2pm 5.3
Moderate
3pm 4.2
Moderate
4pm 2.7
Low
5pm 1.2
Low
6pm 0.3
Low
7pm 0
Low
8pm 0
Low
9pm 0
Low
10pm 0
Low
11pm 0
Low

The UV index forecast for Wednesday, October 22nd in Johnston, SC 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
Low
9am 0.4
Low
10am 1.3
Low
11am 2.7
Low
12pm 4.2
Moderate
1pm 5
Moderate
2pm 5
Moderate
3pm 4
Moderate
4pm 2.6
Low
5pm 1.2
Low
6pm 0.3
Low
7pm 0
Low
8pm 0
Low
9pm 0
Low
10pm 0
Low
11pm 0
Low

The UV index forecast for Thursday, October 23rd in Johnston, SC 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
Low
9am 0.3
Low
10am 1.2
Low
11am 2.6
Low
12pm 3.9
Moderate
1pm 4.9
Moderate
2pm 4.8
Moderate
3pm 3.8
Moderate
4pm 2.4
Low
5pm 1.1
Low
6pm 0.3
Low
7pm 0
Low
8pm 0
Low
9pm 0
Low
10pm 0
Low
11pm 0
Low

The UV index forecast for Friday, October 24th in Johnston, SC 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
Low