Pennsylvania cold wave risk
Philadelphia County has the highest cold wave risk in Pennsylvania, scoring 99.8 out of 100 — rated "Very High" by FEMA's National Risk Index.
| # | County | NRI score | Rating |
|---|---|---|---|
| 1 | Philadelphia County | 99.8 | Very High |
| 2 | Lehigh County | 98.9 | Very High |
| 3 | Allegheny County | 98.8 | Very High |
| 4 | Montgomery County | 98.4 | Relatively High |
| 5 | Monroe County | 95.1 | Relatively High |
| 6 | Luzerne County | 94.7 | Relatively High |
| 7 | Berks County | 93.2 | Relatively High |
| 8 | Delaware County | 91.5 | Relatively High |
| 9 | Bucks County | 90.8 | Relatively High |
| 10 | Lancaster County | 90.8 | Relatively High |
| 11 | Lackawanna County | 89.6 | Relatively High |
| 12 | Chester County | 84.2 | Relatively Moderate |
| 13 | Northampton County | 83.8 | Relatively Moderate |
| 14 | Schuylkill County | 78.3 | Relatively Moderate |
| 15 | Carbon County | 76.7 | Relatively Moderate |
| 16 | Pike County | 76.6 | Relatively Moderate |
| 17 | York County | 74.1 | Relatively Moderate |
| 18 | Cambria County | 70.5 | Relatively Moderate |
| 19 | Dauphin County | 67.7 | Relatively Moderate |
| 20 | Wayne County | 63.2 | Relatively Low |
| 21 | Lebanon County | 61.9 | Relatively Low |
| 22 | Indiana County | 57.7 | Relatively Low |
| 23 | Clearfield County | 57.4 | Relatively Low |
| 24 | Blair County | 49 | Relatively Low |
| 25 | Northumberland County | 47.9 | Relatively Low |
| 26 | Jefferson County | 46.6 | Relatively Low |
| 27 | Cumberland County | 42.1 | Relatively Low |
| 28 | Bradford County | 41.2 | Relatively Low |
| 29 | McKean County | 40.4 | Relatively Low |
| 30 | Erie County | 38.9 | Relatively Low |
| 31 | Columbia County | 38.8 | Relatively Low |
| 32 | Susquehanna County | 37.9 | Relatively Low |
| 33 | Warren County | 35.8 | Relatively Low |
| 34 | Clarion County | 35.6 | Relatively Low |
| 35 | Lycoming County | 32.9 | Relatively Low |
| 36 | Elk County | 28.9 | Relatively Low |
| 37 | Wyoming County | 27.6 | Relatively Low |
| 38 | Adams County | 26.5 | Relatively Low |
| 39 | Greene County | 25.3 | Relatively Low |
| 40 | Potter County | 23.6 | Very Low |
| 41 | Mercer County | 23.2 | Very Low |
| 42 | Crawford County | 23.1 | Very Low |
| 43 | Centre County | 22.3 | Very Low |
| 44 | Snyder County | 22.3 | Very Low |
| 45 | Franklin County | 20.8 | Very Low |
| 46 | Union County | 20.8 | Very Low |
| 47 | Perry County | 18.3 | Very Low |
| 48 | Mifflin County | 17.9 | Very Low |
| 49 | Beaver County | 16.8 | Very Low |
| 50 | Lawrence County | 16.4 | Very Low |
| 51 | Butler County | 15.5 | Very Low |
| 52 | Montour County | 15.1 | Very Low |
| 53 | Westmoreland County | 14.9 | Very Low |
| 54 | Tioga County | 14.4 | Very Low |
| 55 | Forest County | 13.4 | Very Low |
| 56 | Juniata County | 13.3 | Very Low |
| 57 | Somerset County | 11.7 | Very Low |
| 58 | Sullivan County | 10.7 | Very Low |
| 59 | Cameron County | 10.6 | Very Low |
| 60 | Venango County | 10.1 | Very Low |
| 61 | Clinton County | 9.6 | Very Low |
| 62 | Armstrong County | 9.4 | Very Low |
| 63 | Huntingdon County | 8.7 | Very Low |
| 64 | Fayette County | 8.5 | Very Low |
| 65 | Washington County | 8.3 | Very Low |
| 66 | Bedford County | 8 | Very Low |
| 67 | Fulton County | 5.6 | Very Low |
Source: FEMA National Risk Index v1.20.0, December 2025. Scores are 0–100 percentile rankings among all US counties. See the methodology page for definitions. Download the full CSV for all counties.
Cold Wave risk nationally:
Other hazard risks in Pennsylvania:
Frequently asked questions
What is the highest cold wave risk county in Pennsylvania?
Philadelphia County, PA has the highest cold wave risk in Pennsylvania, with a FEMA National Risk Index score of 99.8 out of 100 (rated "Very High").
How many counties in Pennsylvania are rated Very High for cold wave risk?
3 of 67 scored Pennsylvania counties are rated "Very High" for cold wave risk by FEMA's National Risk Index.
What causes cold wave risk in Pennsylvania?
Cold wave risk captures expected losses from extended periods of extreme cold, including wind chill. The northern Plains, Great Lakes, and interior New England see the most severe and frequent cold events. Cold extremes cause significant excess mortality, especially among unhoused populations, the elderly, and those with inadequate heating or insulation. Cold and wind chill events are reported at forecast-zone level in NOAA Storm Events and are not included in county-level counts.