Insured lightning-caused property damage in three western states

Abstract

Insurance claims resulting from lightning damage in Colorado, Utah, and Wyoming were analyzed during the period from 1987 to 1993. Most claims were from personal accounts, while some were commercial. Lightning damage in the three states resulted in an annual average of 6755 claims being filed. Most claims were from Colorado, and more than half were from the Denver metropolitan area. Over $7 million a year in lightning losses occurred in the three states for these types of insurance policies when a $150 deductible was included; most losses were in Colorado. The average value paid per claim was $916 for all three states and types of claims; commercial claims averaged $1369, and personal claims averaged $873. One lightning insurance claim was estimated to occur in the three-state region for every 55 cloud-to-ground lightning flashes recorded by detection networks. Nearly all lightning claims were from May through September. The largest number of claims were from counties with the largest populations. However, the claim rate per population and the dollar loss per claim were not well related to county population. A rate of 4.7 claims per 10 000 people applied for Colorado, 1.4 for Utah, and 3.9 for Wyoming. Annual U.S. totals of 307 000 claims and $332 million in losses were extrapolated on the basis of population in the three states. The dataset for Colorado, Utah, and Wyoming had 367 times as many claims as similarly insurable damage reports in the National Oceanic and Atmospheric Administration's Storm Data during the same years. This publication is widely used as the basis for lightning and other storm-related casualty and damage information. The results suggest that Storm Data greatly underestimates lightning damage.