A map compiled using data and risk assessments from the Federal Emergency Management Agency (FEMA) shows the counties in the U.S. that are currently deemed to be the most, and the least, at risk of being vulnerable to wildfires.

San Diego County in southern California has the highest determined risk of wildfires emerging, followed by the neighboring Riverside, San Bernadino and Los Angeles counties, which also have a “very high” risk index score.

The region is particularly prone to bush blazes. In October, thousands of residents of Riverside County were forced to evacuate as a rapidly expanding wildfire destroyed structures. Before it was contained, the Highland Fire burned nearly 2,500 acres.

That followed the York Fire, which grew to 80,000 acres and crossed into Nevada in August.

Ventura and Orange counties in California, Pima and Maricopa counties in Arizona, as well as Washington County, Utah and Elko County, Nevada, all ranked among the top 10 locales deemed to be most at risk of devastation from wildfires.

Conversely, the area with the lowest risk of damaging wildfires is the Aleutian Islands in Alaska, with an index rating near to zero. Six counties in Illinois, one in Virginia and one in Pennsylvania have the lowest risk scores, of less than half a percent.

The map is one of several developed by FEMA to track natural hazards across the U.S. Other maps include the evaluated risk of hurricanes, droughts, heatwaves and river flooding—as well as one that gives a general assessment of the risk of natural hazards overall.

The federal disaster agency says the assessments show the areas that are the “most at risk from the effects of natural hazards and climate change,” and they are used as a “geographic focus for financial and technical assistance.”

Experts agree that as the climate gets warmer on average, more energy will be pushed into the atmosphere, energizing weather systems and making them more erratic. This means that extreme weather events will occur with greater severity, often causing greater hardship to human populations.

The FEMA risk indices are calculated by multiplying the expected annual economic loss due to the natural hazard by the areas’ relative vulnerability to be adversely impacted by natural hazards. This is then divided by a score of the communities’ resilience and preparedness to those hazards relative to other communities that face similar challenges.

As such, an area’s risk score doesn’t represent how likely it is to suffer a natural hazard, but rather how it compares to other counties in coping with the risks it has previously suffered.

For instance, several counties in the Texas panhandle have a “relatively moderate” risk index score, despite last week suffering the state’s largest wildfire in history—and the second largest on U.S. soil—as warm temperatures and strong winds provided the perfect conditions for bush blazes.

The Smokehouse Creek fire prompted mass evacuations and the declaration of a disaster by Texas Governor Greg Abbott, and it is only one of several active fires in the region. As of the latest update, it spans nearly 1.1 million acres and is 15 percent contained.