massoutage

US Natural Hazard & Outage Risk

What is each US county prone to — and how does that translate to power-outage risk? Hazard ratings are from FEMA's National Risk Index; we pair them with a decade of real outage history on every county page.

By hazard

Hurricane
Most at-risk counties →
Earthquake
Most at-risk counties →
Tornado
Most at-risk counties →
Wildfire
Most at-risk counties →
Ice storm
Most at-risk counties →
Flooding
Most at-risk counties →
Heat wave
Most at-risk counties →

Highest overall-risk US counties

By FEMA National Risk Index composite score.

  1. 1Los Angeles County, CAVery High
  2. 2Cook County, ILVery High
  3. 3Harris County, TXVery High
  4. 4Riverside County, CAVery High
  5. 5Maricopa County, AZVery High
  6. 6San Bernardino County, CAVery High
  7. 7Orange County, CAVery High
  8. 8Alameda County, CAVery High
  9. 9Santa Clara County, CAVery High
  10. 10San Diego County, CAVery High
  11. 11King County, WAVery High
  12. 12Dallas County, TXVery High
  13. 13Miami-Dade County, FLVery High
  14. 14Philadelphia County, PAVery High
  15. 15Clark County, NVVery High
  16. 16San Francisco County, CAVery High
  17. 17Contra Costa County, CAVery High
  18. 18Broward County, FLRelatively High
  19. 19Bexar County, TXRelatively High
  20. 20Ventura County, CARelatively High

Source: FEMA National Risk Index (per-county hazard risk ratings). Outage history from DOE/ORNL EAGLE-I. Risk ratings reflect expected annual loss, not a forecast.