riskbycounty
FEMA NRI 1.19.0Updated Nov 2023 · Coverage 2014–2023Methodology

Greene County Disaster Risk

Greene County, Iowa

FEMA Risk Rating

Very Low

National Percentile

32th

of 3,144 counties

State Rank

#59

of 99 (1 = highest risk)

Flood Risk

12th

percentile

Hazard Risk Breakdown

Flood

River, coastal, and surface flooding risk

Very Low

Higher than 12% of US counties

Wildfire

Wildland and wildland-urban interface fire risk

Very Low

Higher than 10% of US counties

Tornado

Tornado and severe thunderstorm risk

Relatively Low

Higher than 66% of US counties

Earthquake

Seismic activity and ground shaking risk

Very Low

Higher than 11% of US counties

Hurricane

Tropical cyclone and hurricane risk

Very Low

Higher than 13% of US counties

Risk Overview

About Natural Disaster Risk in Greene County, Iowa

Greene ranks well below national risk

Greene County's composite risk score of 31.77 sits substantially below the national average, earning a "Very Low" risk rating. The county faces significantly less natural disaster exposure than typical American communities.

Below-average risk for Iowa

Greene County scores 31.77 versus Iowa's 39.68 state average, placing it among the safer Iowa counties. The county enjoys lower natural hazard exposure than most of its statewide peers.

Mid-range safety in central Iowa

Greene County's 31.77 score places it between Fremont (14.98) and Fayette (50.89) counties regionally, occupying a moderate-safety tier. It ranks safer than both Fayette and Floyd to the northeast, but faces slightly higher risk than Fremont to the southwest.

Tornadoes the primary concern

Tornado risk dominates Greene County's hazard profile at 65.52, the leading threat residents face. Flood and wildfire risks remain low at 12.02 and 10.31 respectively, creating a tornado-focused risk environment.

Prioritize tornado readiness

Greene County residents should maintain standard homeowners insurance and develop a household tornado safety plan with a designated shelter location. Flood insurance is unnecessary for most properties, but all residents should practice tornado drills during spring storm season.

Source: FEMA National Risk Index · Narrative reviewed by Evan Brooks, Data Editor

Preparedness Guide

What to Prepare for in Greene County

Top Hazards by Exposure

  1. #1
    TornadoPrepare
    66th percentile
  2. #2
    HurricanePrepare
    13th percentile
  3. #3
    FloodPrepare
    12th percentile

Source: FEMA National Risk Index v1.19.0 · Percentiles are national (3,144 counties)

Risk Advisory: Greene County

Risk Verdict

Greene County carries a low natural disaster risk burden, scoring at the 32th percentile under the FEMA National Risk Index. Even at the 32th percentile, Greene County's composite score reflects real hazard exposure categories — knowing which ones apply locally enables targeted, efficient household preparedness.

Hazard Breakdown

Tornado risk is Greene County's dominant natural hazard, ranked at the 66th percentile nationally under FEMA's National Risk Index. Hurricane ranks second at the 13th percentile nationally. Additional tracked hazards include flood (12th percentile), earthquake (11th percentile), wildfire (10th percentile).

Preparedness Context

Greene County's primary hazard, tornado, ranks at the 66th percentile nationally. In Greene County, mobile homes and manufactured housing face significantly higher tornado risk than site-built structures; residents in these homes should identify the nearest permanent community shelter in advance. Hurricane is the second hazard driver for Greene County at the 13th percentile nationally, meaning households should maintain awareness of both severe-weather and hurricane-specific warning systems. The highest-risk window for tornado fatalities is overnight, when Greene County residents may be asleep. A NOAA weather radio with overnight alert capability is the single most impactful low-cost preparedness step available to Greene County households.

Regional Context

Compared to the Iowa county average, Greene County's composite score runs 7.9 points lower — a gap that reflects the county's relatively modest hazard profile within its state context.

Is your household prepared for Greene County's hazards?

Review FEMA's county-specific preparedness checklists and emergency planning guides.

FEMA Ready Guide →

Frequently Asked Questions

What is the natural disaster risk in Greene County, IA?
Greene County has a FEMA National Risk Index rating of Very Low, placing it in the 32th percentile nationally out of 3,144 counties. This composite score reflects the county's overall exposure to natural hazards including floods, wildfires, tornadoes, earthquakes, and hurricanes, weighted by expected annual loss and social vulnerability.
What types of natural hazards affect Greene County?
Greene County is evaluated for five major natural hazard types: tornado (66th percentile), hurricane (13th percentile), flooding (12th percentile), earthquake (11th percentile), wildfire (10th percentile). The highest-risk hazard is tornado at the 66th percentile nationally. These scores are derived from FEMA's National Risk Index, which analyzes expected annual loss, social vulnerability, and community resilience for each hazard type.
How does Greene County risk compare to the Iowa average?
Greene County's composite risk percentile is 32th, compared to the Iowa state average of 40th percentile. The state's overall risk rating is Very Low. This means Greene County faces lower natural disaster risk than the typical county in Iowa.
Is Greene County at risk for tornado?
Yes, Greene County's tornado risk is at the 66th percentile nationally. This is above the national median. For flooding specifically, Greene County is at the 12th percentile.
How is natural disaster risk measured?
FEMA's National Risk Index (NRI) calculates risk scores for 18 natural hazard types across all U.S. counties and census tracts. The composite score combines Expected Annual Loss (estimated dollar losses from each hazard), Social Vulnerability (demographic factors affecting disaster impact), and Community Resilience (ability to recover). Percentile scores rank each county against all 3,144 U.S. counties, and risk ratings range from Very Low to Very High.
Is Greene County a safe place to live?
Greene County's composite risk score of 32th percentile is below the Iowa state average of 40th percentile, indicating relatively lower exposure to natural hazards. However, no county is completely risk-free. The primary hazard type is tornado at the 66th percentile. Residents should still maintain emergency preparedness plans and appropriate insurance coverage.
By Evan Brooks, Data EditorUpdated Reviewed by Evan Brooks, Data Editor

Data Source

Risk data sourced from the FEMA National Risk Index (NRI). Risk scores are relative rankings (0–100) across all US counties — not absolute risk measures. Higher scores indicate higher relative risk compared to other counties.

Disclaimer: This data is informational only. It is not financial, insurance, or legal advice. Always consult a qualified professional before making insurance or real estate decisions.