Peak UV index by city
| City | Population | Peak UV | Exposure | UV 3+ hours |
|---|---|---|---|---|
| Portland | 69,911 | 3 | Moderate | 12 PM–1 PM |
| Lewiston | 38,866 | 2 | Low | Below 3 all day |
| Bangor | 32,518 | 2 | Low | Below 3 all day |
| South Portland | 27,007 | 3 | Moderate | 12 PM–1 PM |
| Auburn | 25,441 | 2 | Low | Below 3 all day |
UV 3+ hours show the window from the first forecast hour at 3 or above to the end of the last. The EPA recommends sun protection at UV 3 and above. Open a city for its current-hour forecast and hourly chart. Forecast sources and limitations.