RiskByCounty presents county fields from FEMA National Risk Index v1.20, released in December 2025. The displayed values are source fields and deterministic display transformations; they are not original reporting or an individualized assessment.
FEMA describes the National Risk Index as a planning dataset for comparing natural-hazard risk across U.S. communities. Its composite NRI covers 18 natural hazards. RiskByCounty displays the composite county value and five selected categories from that larger source.
What RiskByCounty displays
The five selected categories are flood, wildfire, tornado, earthquake, and hurricane. They are a display selection, not the complete set used in FEMA’s composite NRI.
Displayed flood is the higher of FEMA Coastal Flooding and Inland Flooding NRI scores. Both source values remain available on each county page so the display rule is transparent.
How to read the values
The displayed scores are unitless relative planning indices. They support comparisons within FEMA’s national dataset; they do not measure the likelihood that a particular event will occur.
These values are not event probabilities, do not estimate future events, and are not property or address assessments. They are also not insurance guidance, not emergency instructions, not evacuation or shelter guidance, and not local-agency advice.
Source limitations
FEMA documents important limitations for geographic scale, source inputs, and comparative use. County values can conceal variation within a county, and missing source values remain unavailable on RiskByCounty rather than being estimated.
RiskByCounty preserves FEMA’s composite county score and official county rating. State and national summaries elsewhere on this site are explicitly labeled RiskByCounty arithmetic summaries of available county values, not FEMA state scores or ratings.
Official FEMA documentation
Use FEMA’s own methodology and data documentation for field definitions, source notes, and the agency’s complete limitation statements.
Source: FEMA National Risk Index v1.20, released December 2025. RiskByCounty presents deterministic transformations of frozen FEMA county fields; the values are unitless relative planning indices and do not estimate future events.