More than half of all homes, 56 percent, in the contiguous 48 states face at least some wildfire risk in the next few decades, according to a first-of-its-kind report published today by the nonprofit research organization First Street Foundation.

First Street gave each address in the continental US a rating between one to 10, with one representing close to no risk and 10 representing a 36 percent or more likelihood that a property could be caught up in a wildfire sometime during the next three decades. More than 20 million properties across the continental US are threatened by at least “moderate” wildfire risk. Those homes have up to a 6 percent chance of being in a blaze at some point over a 30-year timespan, the typical timeframe for a home mortgage. 

Even a 1 percent chance of being in a wildfire is worth taking seriously. In comparison, the federal government considers an area with a 1 percent chance of flooding in a given year as a “Special Flood Hazard Area” on maps used to determine flood insurance rates. But unlike flooding, The New York Times reports, there hasn’t been comprehensive property-level data on wildfire risk until now.

Now, you can type an address into First Street’s online search tool to see the organization’s fire risk rating for that property (you’ll also find a flood risk rating from First Street). The information will also be incorporated into Realtor.com. 

To assess each property’s risk, First Street built a peer-reviewed model using government data on available fuels (dry vegetation) and weather patterns. Then it was able to simulate over 100 million wildfires to see which properties they might threaten. 

Using First Street’s Data, The Washington Post reports that one in six Americans now lives in a place with “significant” wildfire risk.

Wildfire seasons have become more intense as climate change makes the Western US hotter and drier. The past century of fire suppression has also made fires more devastating when they do break out since suppression tactics have allowed dry vegetation to build up to dangerous levels instead of allowing them to burn off in smaller, sporadic blazes. On top of that, residents have moved deeper into vulnerable locations where urban development meets fire-prone ecosystems, especially in states with soaring housing prices like California. There’s been an almost tenfold increase in costs associated with wildfires from $8.5 billion between 2012 and 2016 to $79.8 billion in costs from 2018 to 2021, according to the National Oceanic and Atmospheric Administration.

Things are only going to get riskier as climate change continues to heat the planet, The Washington Post and First Street both warn. In 30 years, about one in five Americans will live in areas with significant risk.