Natural Disaster Risk in Johnston

Natural Hazard Profile: Johnston, Iowa

Located in the interior eastern United States in Polk County, Johnston is a city of approximately 24,583 residents. The humid continental climate that characterizes this part of Iowa — marked by cold winters, hot summers, and frequent severe weather — directly influences the types and severity of natural hazards present, making Johnston a community where hazard awareness has real practical value.

FEMA rates Johnston's composite natural disaster risk at 7.7 out of 10 — high risk. High-wind events from severe thunderstorms and derechos are the leading hazard, with damaging gusts capable of downing trees and causing widespread structural damage. Residents should also account for hail and tornado risk in their preparedness planning.

Relative to other U.S. communities, Johnston's natural disaster risk is well above the U.S. national average of 4.5/10, considerably above the 5.4/10 state average. The hazard distribution here is led by wind and hail, as measured by FEMA across Polk County. While city-specific sub-county variation exists, these scores represent the best available federal risk estimate.

With a high natural disaster risk rating, Johnston residents benefit from taking preparedness seriously. Reviewing insurance coverage for wind and secondary hazards, registering for emergency alerts, and maintaining a household emergency kit are practical steps that can significantly reduce impact during a major event.