Yellowstone’s Threat: 8 U.S. Communities Most at Risk

Understanding FEMA’s “Zone One” and How a Super Volcano Eruption Could Impact American Towns

By Theodora Filis

There's Something MUCH Bigger Than Yellowstone. And It Will Happen Again.

Introduction

Yellowstone National Park is famous for its stunning landscapes, rich wildlife, and geothermal features. Beneath these natural wonders lies one of the world’s most powerful geological formations: the Yellowstone super volcano. Although a volcanic eruption is a rare event, its potential impact is so significant that scientists and emergency officials closely watch the region. This article highlights the eight American locations most at risk if Yellowstone erupts, with a special focus on a gateway town directly in the line of danger. We will also explain what FEMA’s “Zone One” means, evaluate the chances of an eruption, review warning times for residents, and stress the importance of being prepared.

FEMA’s Zone One: Definition and Significance

The Federal Emergency Management Agency (FEMA) designates “Zone One” as the area most likely to experience catastrophic impacts if a Yellowstone super volcano erupts. This zone includes the immediate area around the caldera—the large crater formed by past eruptions. Residents and communities within Zone One face the greatest risks from pyroclastic flows, ash fallout, and ground collapse. Being in Zone One means that infrastructure, homes, and lives are especially vulnerable, making evacuation plans critically important.

Gateway Town Overview: Life at the Periphery

Near the western edge of Yellowstone’s caldera, a small gateway town with about 1,300 residents is situated. This community falls directly within FEMA’s Zone One, making it one of the most at-risk population centers in the country. The town functions as a primary entry point for visitors entering Yellowstone from the west, supporting tourism-related businesses and residents. However, its proximity to the super volcano means residents would be among the first to experience the destructive effects of an eruption. Emergency planners monitor this town closely because of its location and the challenges of quick evacuation in a disaster.

8 At-Risk American Places

1.      West Yellowstone, Montana: As the gateway town with around 1,300 residents, West Yellowstone is directly adjacent to the caldera’s western boundary. Its position in FEMA’s Zone One makes it the most vulnerable community, with little chance of escape in the event of a sudden eruption.

2.      Island Park, Idaho: Just southwest of Yellowstone, Island Park is known for its scenic beauty and proximity to the park. Its location puts it in the path of potential ash clouds and pyroclastic flows.

3.      Cody, Wyoming: Located east of Yellowstone, Cody could face heavy ashfall, which would threaten infrastructure, health, and transportation.

4.      Jackson, Wyoming: South of the park, Jackson’s population and tourism industry would be at risk from both ash and potential disruption of essential services.

5.      Bozeman, Montana: A regional hub northeast of Yellowstone, Bozeman could experience significant ash accumulation, affecting daily life and air quality.

6.      Billings, Montana: As a major city farther east, Billings might see substantial ashfall, impacting tens of thousands of residents and critical infrastructure.

7.      Idaho Falls, Idaho: Situated southwest of the park, Idaho Falls would likely face air quality hazards and disruption to transportation networks.

8.      Salt Lake City, Utah: Although farther away, prevailing winds could carry ash clouds as far as Salt Lake City, leading to public health risks and economic challenges.

Likelihood of a Yellowstone Eruption

Despite frequent headlines, the chance that Yellowstone will erupt in our lifetime is extremely low. According to the U.S. Geological Survey, the odds of a major eruption in any given year are about 1 in 730,000—much lower than other natural disasters like earthquakes or hurricanes. Scientists keep an eye on the area for signs of activity, but there’s no evidence that an eruption is imminent. The last significant eruption happened around 640,000 years ago, and the volcano currently shows no signs of preparing for a similar event.

Warning Time for Residents

Yellowstone is one of the most closely monitored volcanoes in the world. A network of seismic sensors, GPS stations, and satellite systems continuously observes ground movement, gas emissions, and other signs of volcanic activity. If Yellowstone shows signs of an impending eruption, experts estimate that residents could receive a warning anywhere from days to weeks in advance. This period would enable emergency alerts and, if possible, the evacuation of vulnerable communities. However, for those in FEMA’s Zone One—such as the gateway town on the caldera’s western edge—evacuation plans would need to be carried out swiftly, as the most severe impacts would occur very close to the eruption site.

Conclusion: Preparedness and Public Awareness

Although the chance of a catastrophic Yellowstone eruption is extremely low, understanding the risks and identifying which communities are most vulnerable is crucial for preparedness. Towns like West Yellowstone and others in FEMA’s Zone One face specific challenges because of their proximity to the super volcano. Continuous scientific monitoring, community education, and solid evacuation plans are the best ways to protect lives in the unlikely event of an eruption. Staying informed and prepared is vital to reducing risk and maintaining public safety.