Los Angeles County has come out No. 1 on an unenviable list—the Federal Emergency Management Agency’s rankings of the riskiest counties in the United States.

The agency has published its first National Risk Index, which ranks all 3,006 counties in the nation based on their vulnerability to 18 kinds of natural disasters, from earthquakes, hurricanes, wildfires and tornadoes to floods, volcanoes and tsunamis.

LA County finished first. The rest of the top 10—or bottom 10—were Bronx, Manhattan, Brooklyn, Miami, Philadelphia, Dallas, St. Louis, Riverside and San Bernardino.

FEMA officials began work on the index in 2016. It is intended to help planners and emergency managers at the local, regional, state and federal levels in updating their emergency operations plans, prioritize and allocate resources, educate homeowners and renters and encourage community-level risk communication and engagement.

The rankings do not necessarily mean that LA County residents are more likely than others to fall victim to a natural disaster. A central component of the index was expected annual loss, which quantifies the anticipated economic damage resulting from natural hazards each year.

The data also take into account social vulnerability, which is broadly defined as the susceptibility of social groups to the adverse impacts of natural hazards, including disproportionate death, injury, loss or disruption of livelihood.

The 18 natural hazards included in the index were: avalanche, coastal flooding, cold wave, drought, earthquake, hail, heat wave, hurricane, ice storm, landslide, lightning, riverine flooding, strong wind, tornado, tsunami, volcanic activity, wildfire and winter weather.

The “safest” county was Loudoun County, a suburb of Washington, D.C. Three other Washington suburban counties ranked among the lowest risks for larger counties, along with suburban counties near Boston, Long Island, Detroit and Pittsburgh.

For more, visit www.fema.gov/flood-maps/products-tools/national-risk-index.