Peak UV index by city
| City | Population | Peak UV | Exposure | UV 3+ hours |
|---|---|---|---|---|
| Philadelphia | 1,574,281 | 3 | Moderate | 11 AM–2 PM |
| Pittsburgh | 307,632 | 3 | Moderate | 12 PM–2 PM |
| Allentown | 126,044 | 3 | Moderate | 11 AM–2 PM |
| Reading | 95,832 | 3 | Moderate | 11 AM–2 PM |
| Erie | 91,838 | 3 | Moderate | 12 PM–1 PM |
| Bethlehem | 79,644 | 3 | Moderate | 11 AM–2 PM |
| Scranton | 75,514 | 3 | Moderate | 11 AM–2 PM |
| Lancaster | 58,366 | 3 | Moderate | 11 AM–2 PM |
| Harrisburg | 50,522 | 3 | Moderate | 11 AM–2 PM |
| York | 45,342 | 3 | Moderate | 11 AM–2 PM |
| Wilkes-Barre | 44,523 | 3 | Moderate | 11 AM–2 PM |
| Altoona | 42,347 | 3 | Moderate | 12 PM–2 PM |
| State College | 40,844 | 3 | Moderate | 12 PM–2 PM |
| Penn Hills | 39,452 | 3 | Moderate | 12 PM–2 PM |
| Norristown | 35,911 | 3 | Moderate | 11 AM–2 PM |
| Chester | 33,996 | 3 | Moderate | 11 AM–2 PM |
| Mount Lebanon | 32,552 | 3 | Moderate | 12 PM–2 PM |
| Bethel Park | 32,074 | 3 | Moderate | 12 PM–1 PM |
| Easton | 30,402 | 3 | Moderate | 11 AM–2 PM |
| Hazleton | 30,286 | 3 | Moderate | 11 AM–2 PM |
| Monroeville | 27,685 | 3 | Moderate | 12 PM–2 PM |
| Williamsport | 27,384 | 3 | Moderate | 11 AM–2 PM |
| Lebanon | 26,479 | 3 | Moderate | 11 AM–2 PM |
| Plum | 26,225 | 3 | Moderate | 12 PM–2 PM |
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.
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