As of 11:07 AM EDT on June 5, 2026, all 11 cities in Johnston County, NC in our database have a UV Index reading of High. The city with the highest UV Index reading right now is Smithfield, NC with a reading of 6.8.
Over the next 24 hours, the highest UV Index reading in Johnston County, NC is expected to be 9.6 in Clayton between 1:00 PM - 2:00 PM EDT today.
| Range | 0 - 2 | 3 - 5 | 6 - 7 | 8 - 10 | 11+ |
|---|---|---|---|---|---|
| Color | |||||
| Risk | Low | Moderate | High | Very High | Extreme |