Natural hazards or earth hazards are events or processes that have significant impacts on human beings and the environment. Extreme weather conditions or geologic activity can cause substantial short-term or long-term changes to our environment. These changes can influence many aspects of the world around us, including crops, homes, infrastructure, and the atmosphere. The 4.6-billion-year-old Earth has experienced many naturally generated hazards, while other events are byproducts of human activities, created during mineral and energy extraction or in construction practices that modify the landscape.

The Southwest, like any other part of the US, has numerous hazards—based largely on its geography—that directly infringe upon people’s property and safety. Dangerously hot weather and drought are commonplace in the Southwest’s arid environment. Weather hazards such as tornados, thunderstorms, and winter storms frequently occur over the Great Plains, thanks to the unobstructed movement of air masses over areas of low topographic relief. The Rocky Mountains are susceptible to extreme winter weather such as heavy snow, blizzards, and high winds. Flooding can occur in areas of low elevation and along large rivers. Geological hazards, including avalanches, earthquakes, landslides, and rockfalls, also occur throughout the Southwest, especially in areas with rugged, mountainous terrain.