ATTOM Data Solutions released its 2018 U.S. Natural Hazard Housing Risk Index, which found that median home prices in cities with the top 80th percentile for natural hazard housing risk have appreciated 40 percent on average over the last 10 years — 1.7 times the 24 percent home price appreciation in the overall U.S. housing market during the same time period.
For the report ATTOM indexed natural hazard risk in more than 3,000 counties and more than 22,000 U.S. cities based on the risk of six natural disasters: earthquakes, floods, hail, hurricane storm surge, tornadoes, and wildfires. ATTOM also analyzed housing trends in 2,616 cities and 440 counties — containing more than 53 million single family homes and condos — broken into five equal quintiles of natural hazard housing risk.
“While combined natural disaster risk has not seemed to hobble home price appreciation over the past decade, the story is much different for some individual hazard risks — namely flood, hurricane storm surge and wildfire risk,” said Daren Blomquist, senior vice president at ATTOM Data Solutions. “Home price appreciation in the overall U.S. housing market was double the rate of appreciation in cities with the highest flood risk and triple the rate of appreciation in cities with the highest hurricane storm surge risk over the past 10 years. The broader market has also outperformed appreciation in cities with the highest wildfire risk during the last decade, although the gap is much narrower.”
Foreclosure rates elevated in highest-risk flood cities
Foreclosure rates were lower in cities in the top 80th percentile for natural hazard housing risk, and this was true for all individual natural hazard risk types except for flood risk. In cities in the top 80th percentile for flood risk, active foreclosures represented 0.61 percent of all properties, well above the foreclosure rate of 0.38 percent across all risk categories.
“Weather is the largest external swing factor in U.S. economics and accounts for over $550 billion per year in lost revenue and up to 76,000 lost jobs,” said Mark Gibbas, president and CEO at WeatherSource, a technology company that provides global weather and climate data along with advanced analytics. “Weather can have an enormous impact on homeowners and the housing market. When big weather events such as hurricanes, tornados and hail hit, many homeowners suffer financial hardship from various sources such as lost wages and losses due to inadequate insurance. And while the impact on homeowners can be severe, hurricanes like Harvey can change the landscape of the housing market region wide, including shifts in the number of available homes and shifts in home values.”
Cities with the highest flood risk also posted seriously underwater rates (loan-to-value ratio of 125 percent or higher) above the overall market average — 8.9 percent of all homes with a mortgage compared to 8.5 percent nationwide. Tornado risk was the only other individual natural hazard risk factor with seriously underwater rates above the market average in the highest risk cities — 10.0 percent of all homes with a mortgage.
Buyers paid a premium for homes in highest-risk cities in 2018
The report also shows that homebuyers so far in 2018 paid an average 1.0 percent premium above estimated market value for homes in cities with the highest natural disaster risk while homes in cities with the lowest natural disaster risk sold at an average 3.7 percent discount below estimated market value.
The exception to this trend was in cities with the highest flood risk, where homes sold at an average 2.4 percent discount below estimated market value, cities with the highest tornado risk (2.2 percent discount below estimated market value), and cities with the highest hurricane storm surge risk (1.4 percent discount below estimated market value).
Counties and cities with highest natural hazard risk index
Among the 2,616 cities analyzed in the report with sufficient housing trend data, those with the top 20 highest natural hazard housing risk indexes were all located in the following metropolitan statistical areas: Oklahoma City, Oklahoma; San Diego, California; Clearlake, California; San Jose, California; Madera, California; Riverside-San Bernardino, California, Bakersfield, California; Houston, Texas, Santa Cruz, California; and Huntsville, Alabama.
Among the 440 counties analyzed in the report with sufficient housing trend data, those with the highest natural hazard housing risk indexes were Oklahoma County, Oklahoma (Oklahoma City); Monroe County, Florida (Key West); Santa Cruz County, California (Santa Cruz); Santa Clara County, California (San Jose); and Marin County, California (San Francisco).
Among those same 440 counties, those with the lowest natural hazard housing risk indexes were Milwaukee County, Wisconsin (Milwaukee); Muskegon County, Michigan (Muskegon); Cuyahoga County, Ohio (Cleveland); Kenosha County, Wisconsin (Chicago metro); and Monroe County, New York (Rochester).
For its fifth annual Natural Hazard Housing Risk Index, ATTOM Data Solutions indexed more than 3,000 U.S. counties and more than 22,000 U.S. cities based on risk of six natural disasters: earthquakes, floods, hail, hurricane storm surge, tornadoes and wildfires. ATTOM also analyzed home sales and price trends in 440 counties and 2,616 cities with sufficient property data.
A risk index was created for each of the six natural hazards in each city and count with natural hazard data available. Each natural hazard index was divided into five categories of risk: Very High, High, Moderate, Low and Very Low based on a severity scale. Those six natural hazard indexes were summed to create a Total Natural Hazard Index. The maximum index for each category of risk is 60, and the maximum possible total index score is 360.
For the home sales and price trends analysis, the indexes in 735 counties and 3,441 cities were split into five equal groups (quintiles) matching the aforementioned five categories of risk.
Flood zone data is based on flood zones created by the Federal Emergency Management Agency (FEMA), and the level of risk was based on the percentage of homes in each county located in high-risk flood zones: A, A99, AE, AH, A.
Earthquake data is from the United States Geological Survey (USGS), and the level of risk was based on the probability of a magnitude 5.0 earthquake in each county.
Tornado data is from the National Oceanic and Atmospheric Administration (NOAA), and level of risk was based on the Destruction Potential Index (DPI) for each county. DPI is calculated using number of tornados, path of tornados in square miles, and intensity of tornados on the Fujita scale (FO to F5).
Wildfire data is from the United States Department of Agriculture Forest Service and Fire Modeling Institute, and risk level is based on the percentage of homes in each county located in “Very High” or “High” Wildfire Hazard Potential (WHP) areas.
Hurricane storm surge data is from FEMA and the National Hurricane Center (NHC), and risk level is based on the percentage of homes located in flood zones identified as having a risk of “storm-induced waves”: V and VE.
Hail data is from NOAA and the risk level is based on the average number of hail storms per year in each county with hail that exceeds 1-inch in size over the past 15 years.