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

Grayson County Disaster Risk

Grayson County, Texas

FEMA Risk Rating

Relatively Low

National Percentile

80th

of 3,144 counties

State Rank

#52

of 254 (1 = highest risk)

Flood Risk

80th

percentile

Hazard Risk Breakdown

Flood

River, coastal, and surface flooding risk

Relatively Low

Higher than 80% of US counties

Wildfire

Wildland and wildland-urban interface fire risk

Moderate

Higher than 86% of US counties

Tornado

Tornado and severe thunderstorm risk

Moderate

Higher than 93% of US counties

Earthquake

Seismic activity and ground shaking risk

Relatively Low

Higher than 67% of US counties

Hurricane

Tropical cyclone and hurricane risk

Relatively Low

Higher than 53% of US counties

Risk Overview

About Natural Disaster Risk in Grayson County, Texas

Grayson County faces elevated tornado risk

Grayson County's composite risk score of 80.31 ranks as relatively low but significantly exceeds the Texas state average of 49.00. The county's tornado score of 92.88 is exceptionally high, reflecting its position in a region prone to severe spring storms.

Among Texas's top tornado-prone counties

With a tornado risk score of 92.88, Grayson County ranks in the highest tier statewide for tornado exposure—among the most dangerous tornado counties in Texas. This elevated threat, combined with moderate flood risk (79.52), makes the county particularly vulnerable to spring weather systems.

Tornado risk exceeds neighboring areas

Grayson County's tornado score of 92.88 surpasses similar-sized neighboring counties and is second only to Gregg County (97.90) in the region. The county's position near the Oklahoma border puts it in a natural corridor for spring severe weather.

Tornadoes and floods are primary threats

Tornado risk (92.88) dominates Grayson County's hazard profile, with spring storms regularly producing dangerous conditions across the county. Flood risk (79.52) and wildfire risk (86.04) are also notable secondary threats that affect different areas and seasons.

Prepare for severe weather season

Grayson County residents should have a tornado safety plan, including a designated shelter area, weather alert system, and emergency supplies. Ensure your homeowners policy covers wind and hail damage from severe storms, and consider storm-resistant roofing materials and reinforced garage doors in high-risk areas.

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

Preparedness Guide

What to Prepare for in Grayson County

Top Hazards by Exposure

  1. #1
    TornadoPrepare
    93th percentile
  2. #2
    WildfirePrepare
    86th percentile
  3. #3
    FloodPrepare
    80th percentile

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

Risk Advisory: Grayson County

Risk Verdict

Grayson County has a below-average natural disaster risk profile, scoring at the 80th percentile nationally under FEMA's National Risk Index. This risk level calls for more than general awareness: insurance coverage review, a family communication plan, and a prepared go-bag are practical priorities.

Hazard Breakdown

Tornado risk is Grayson County's dominant natural hazard, ranked at the 93th percentile nationally under FEMA's National Risk Index. Wildfire ranks second at the 86th percentile nationally. Additional tracked hazards include flood (80th percentile), earthquake (67th percentile), hurricane (53th percentile).

Preparedness Context

Tornado risk is Grayson County's top-ranked natural hazard at the 93th percentile nationally. For Grayson County households, the most protective action available is identifying a reinforced interior room on the lowest floor — a bathroom, closet, or central hallway away from windows. Alongside tornado exposure, wildfire at the 86th percentile nationally means Grayson County households face multi-hazard severe-weather seasons that benefit from a single integrated emergency plan covering both threats. A battery-powered NOAA All Hazards weather radio with an auto-alert tone is the highest-leverage single item for tornado preparedness in Grayson County, since it delivers warnings even when power is out and phone networks are congested.

Regional Context

Grayson County's composite risk score sits 31.3 points above the Texas county average, placing it among the more hazard-exposed counties in the state.

Is your household prepared for Grayson 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 Grayson County, TX?
Grayson County has a FEMA National Risk Index rating of Relatively Low, placing it in the 80th 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 Grayson County?
Grayson County is evaluated for five major natural hazard types: tornado (93th percentile), wildfire (86th percentile), flooding (80th percentile), earthquake (67th percentile), hurricane (53th percentile). The highest-risk hazard is tornado at the 93th 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 Grayson County risk compare to the Texas average?
Grayson County's composite risk percentile is 80th, compared to the Texas state average of 49th percentile. The state's overall risk rating is Relatively Low. This means Grayson County faces higher natural disaster risk than the typical county in Texas.
Is Grayson County at risk for tornado?
Yes, Grayson County's tornado risk is at the 93th percentile nationally. This places it in the top quartile for this hazard type. For flooding specifically, Grayson County is at the 80th 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.
Why is Grayson County higher risk than average?
Grayson County's composite risk score of 80th percentile is above the Texas state average of 49th percentile. This elevated risk is driven by tornado exposure (93th percentile), along with wildfire and flooding and earthquake and hurricane risk. Geographic location, terrain, climate patterns, and proximity to flood zones or fault lines all influence a county's risk profile.
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.