Tornado Risk in Pennsylvania
All Pennsylvania counties ranked by FEMA National Risk Index tornado score
Tornado risk — violently rotating columns of air capable of catastrophic local damage — is rated for 67 of 67 Pennsylvania counties in FEMA's National Risk Index. Philadelphia County carries the state's highest tornado score at 98.7, with $21M in expected annual tornado losses.
6 Pennsylvania counties are rated High or Very High for tornado, and expected annual losses from tornado total roughly $153M statewide. The full ranking below links to each county's complete 18-hazard risk profile.
County Rankings — Tornado
| # | County | Tornado Score | Rating | Ann. Freq. | Ann. Loss |
|---|---|---|---|---|---|
| 1 | Philadelphia County | High | 0.07 / yr | $21M | |
| 2 | Montgomery County | High | 0.25 / yr | $15M | |
| 3 | Delaware County | High | 0.10 / yr | $9M | |
| 4 | Bucks County | High | 0.29 / yr | $10M | |
| 5 | Allegheny County | High | 0.28 / yr | $8M | |
| 6 | Berks County | High | 0.47 / yr | $7M | |
| 7 | Chester County | Medium | 0.45 / yr | $10M | |
| 8 | Lehigh County | Medium | 0.18 / yr | $5M | |
| 9 | Luzerne County | Medium | 0.35 / yr | $4M | |
| 10 | Northampton County | Medium | 0.17 / yr | $4M | |
| 11 | Lancaster County | Medium | 0.59 / yr | $4M | |
| 12 | Dauphin County | Medium | 0.28 / yr | $4M | |
| 13 | Lebanon County | Medium | 0.20 / yr | $3M | |
| 14 | Fayette County | Medium | 0.21 / yr | $2M | |
| 15 | Cumberland County | Medium | 0.29 / yr | $3M | |
| 16 | Lackawanna County | Medium | 0.15 / yr | $2M | |
| 17 | Erie County | Medium | 0.32 / yr | $2M | |
| 18 | Schuylkill County | Medium | 0.38 / yr | $2M | |
| 19 | Monroe County | Medium | 0.24 / yr | $2M | |
| 20 | Cambria County | Low | 0.20 / yr | $2M | |
| 21 | Butler County | Low | 0.33 / yr | $2M | |
| 22 | Blair County | Low | 0.17 / yr | $2M | |
| 23 | Beaver County | Low | 0.19 / yr | $2M | |
| 24 | Westmoreland County | Low | 0.34 / yr | $2M | |
| 25 | Mercer County | Low | 0.28 / yr | $1M | |
| 26 | Crawford County | Low | 0.35 / yr | $1M | |
| 27 | Lycoming County | Low | 0.39 / yr | $1M | |
| 28 | Washington County | Low | 0.29 / yr | $1M | |
| 29 | York County | Low | 0.57 / yr | $1M | |
| 30 | Susquehanna County | Low | 0.25 / yr | $1M | |
| 31 | Northumberland County | Low | 0.20 / yr | $1M | |
| 32 | Franklin County | Low | 0.39 / yr | $1M | |
| 33 | Adams County | Low | 0.32 / yr | $1M | |
| 34 | Centre County | Low | 0.35 / yr | $893K | |
| 35 | Indiana County | Low | 0.27 / yr | $762K | |
| 36 | Mifflin County | Low | 0.16 / yr | $604K | |
| 37 | Clearfield County | Low | 0.31 / yr | $760K | |
| 38 | Carbon County | Low | 0.16 / yr | $799K | |
| 39 | Lawrence County | Low | 0.16 / yr | $745K | |
| 40 | Snyder County | Low | 0.13 / yr | $620K | |
| 41 | Columbia County | Low | 0.20 / yr | $780K | |
| 42 | Somerset County | Low | 0.31 / yr | $631K | |
| 43 | Greene County | Low | 0.15 / yr | $619K | |
| 44 | Venango County | Low | 0.25 / yr | $564K | |
| 45 | Armstrong County | Low | 0.24 / yr | $637K | |
| 46 | Union County | Low | 0.12 / yr | $499K | |
| 47 | Bradford County | Low | 0.35 / yr | $565K | |
| 48 | Perry County | Low | 0.26 / yr | $582K | |
| 49 | Jefferson County | Low | 0.20 / yr | $386K | |
| 50 | Wayne County | Low | 0.22 / yr | $480K | |
| 51 | Clarion County | Low | 0.22 / yr | $414K | |
| 52 | Pike County | Low | 0.19 / yr | $431K | |
| 53 | Clinton County | Low | 0.24 / yr | $344K | |
| 54 | Huntingdon County | Low | 0.31 / yr | $399K | |
| 55 | Juniata County | Low | 0.16 / yr | $301K | |
| 56 | Bedford County | Very Low | 0.34 / yr | $348K | |
| 57 | McKean County | Very Low | 0.21 / yr | $294K | |
| 58 | Tioga County | Very Low | 0.28 / yr | $296K | |
| 59 | Warren County | Very Low | 0.23 / yr | $259K | |
| 60 | Wyoming County | Very Low | 0.14 / yr | $239K | |
| 61 | Montour County | Very Low | 0.05 / yr | $221K | |
| 62 | Elk County | Very Low | 0.20 / yr | $220K | |
| 63 | Fulton County | Very Low | 0.17 / yr | $151K | |
| 64 | Potter County | Very Low | 0.24 / yr | $120K | |
| 65 | Forest County | Very Low | 0.12 / yr | $84K | |
| 66 | Sullivan County | Very Low | 0.15 / yr | $78K | |
| 67 | Cameron County | Very Low | 0.09 / yr | $58K |
67 Pennsylvania counties with measurable tornado risk. See the national tornado ranking or all Pennsylvania counties by overall risk.
Frequently Asked Questions
Which Pennsylvania county has the highest tornado risk?
Philadelphia County has the highest FEMA tornado risk score in Pennsylvania at 98.7 (High), with $21M in expected annual losses and about 0.07 events per year.
How many Pennsylvania counties face significant tornado risk?
67 Pennsylvania counties record measurable tornado risk in FEMA's National Risk Index; 6 of them are rated High or Very High.