Lightning

Lightning is a visible electrical discharge or spark of electricity in the atmosphere between clouds, the air and/or the ground often produced by a thunderstorm.

In the National Risk Index, a Lightning Risk Index score and rating represent a community's relative risk for Lightning when compared to the rest of the United States. A Lightning Expected Annual Loss score and rating represent a community's relative level of expected building and population loss each year due to Lightning when compared to the rest of the United States.

A map of the United States colored by Lightning Risk Index ratings. Lightning risk is possible and prevalent across the United States with lower risk along the West Coast. For full results, see the National Risk Index Map webpage.

Click to view map Data Download

Lightning Exposure

A Lightning exposure value represents a community's building value (in dollars) and population (in both people and population equivalence) exposed to Lightning.

Lightning Annualized Frequency

A Lightning annualized frequency value represents the average number of recorded Lightning hazard occurrences (events) per year over the period of record (22 years).

Source Data

National Oceanic and Atmospheric Administration's National Centers for Environmental Information's Cloud-to-Ground Lightning Strikes

Lightning Historic Loss Ratio

A Lightning historic loss ratio is the representative percentage of the exposed consequence type value (building or population) expected to be lost due to a Lightning hazard occurrence.

Lightning Processing Methodology

For comprehensive details about the Lightning processing methodology, see the National Risk Index Technical Documentation.

View Disclaimer