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

St. Tammany Parish Disaster Risk

St. Tammany Parish, Louisiana

FEMA Risk Rating

Relatively High

National Percentile

97th

of 3,144 counties

State Rank

#4

of 64 (1 = highest risk)

Flood Risk

94th

percentile

Hazard Risk Breakdown

Flood

River, coastal, and surface flooding risk

Moderate

Higher than 94% of US counties

Wildfire

Wildland and wildland-urban interface fire risk

Moderate

Higher than 90% of US counties

Tornado

Tornado and severe thunderstorm risk

Moderate

Higher than 87% 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 High

Higher than 99% of US counties

Risk Overview

About Natural Disaster Risk in St. Tammany Parish, Louisiana

St. Tammany faces highest national exposure

St. Tammany Parish's composite risk score of 96.56 places it among America's most disaster-prone counties, earning a "Relatively High" rating. The parish confronts extreme exposure across multiple hazard types simultaneously.

Louisiana's riskiest parish by far

St. Tammany's score of 96.56 soars 55% above Louisiana's state average of 62.37, making it the single riskiest parish in the entire state. No other Louisiana parish approaches St. Tammany's exposure level.

Substantially riskier than surrounding parishes

St. Tammany (96.56) far exceeds nearby Tangipahoa Parish (93.32) and surpasses every other adjacent parish statewide. Only St. Tammany carries a "Relatively High" rating; all others rank "Relatively Moderate" or lower.

All hazards present acute threats

Hurricane risk reaches 98.92—the state's highest—while flood risk of 94.21 and tornado risk of 86.58 create a severe triple threat. Wildfire risk of 89.57 also stands exceptionally high, adding a fourth seasonal danger.

Maximum protection is essential

St. Tammany residents should invest in comprehensive homeowners insurance with explicit hurricane and wind coverage, separate flood insurance, and consider a safe room or shelter given the extreme tornado risk of 86.58. Verify that coverage limits reflect the parish's exceptional 98.92 hurricane threat.

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

Preparedness Guide

What to Prepare for in St. Tammany Parish

Top Hazards by Exposure

  1. #1
    HurricanePrepare
    99th percentile
  2. #2
    FloodPrepare
    94th percentile
  3. #3
    WildfirePrepare
    90th percentile

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

Risk Advisory: St. Tammany Parish

Risk Verdict

St. Tammany Parish's composite risk score ranks at the 97th percentile nationally, reflecting genuine multi-hazard exposure for residents. At this risk level, having a documented household preparedness plan — not just awareness — is the meaningful next step for St. Tammany Parish residents.

Hazard Breakdown

Hurricane risk is St. Tammany Parish's dominant natural hazard, ranked at the 99th percentile nationally under FEMA's National Risk Index. Flood ranks second at the 94th percentile nationally. Additional tracked hazards include wildfire (90th percentile), tornado (87th percentile), earthquake (67th percentile).

Preparedness Context

With hurricane ranked at the 99th percentile nationally, St. Tammany Parish sits in a zone where multi-day supply readiness matters: grid outages after landfalling storms can last one to three weeks in heavily affected areas. Flood at the 94th percentile nationally is St. Tammany Parish's secondary hazard, often intensified by the same weather systems that produce hurricane conditions. Insurance gaps are the most common post-hurricane financial shock: standard homeowners policies typically exclude flood damage and may have a separate wind deductible. St. Tammany Parish households benefit from a pre-season insurance review confirming both wind and flood coverage.

Regional Context

The Louisiana county average is 34.2 composite points below St. Tammany Parish's score, a gap that reflects the county's elevated position in the state's hazard distribution.

Is your household prepared for St. Tammany Parish'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 St. Tammany Parish, LA?
St. Tammany Parish has a FEMA National Risk Index rating of Relatively High, placing it in the 97th 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 St. Tammany Parish?
St. Tammany Parish is evaluated for five major natural hazard types: hurricane (99th percentile), flooding (94th percentile), wildfire (90th percentile), tornado (87th percentile), earthquake (67th percentile). The highest-risk hazard is hurricane at the 99th 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 St. Tammany Parish risk compare to the Louisiana average?
St. Tammany Parish's composite risk percentile is 97th, compared to the Louisiana state average of 62th percentile. The state's overall risk rating is Relatively Low. This means St. Tammany Parish faces higher natural disaster risk than the typical county in Louisiana.
Is St. Tammany Parish at risk for hurricane?
Yes, St. Tammany Parish's hurricane risk is at the 99th percentile nationally. This places it in the top quartile for this hazard type. For flooding specifically, St. Tammany Parish is at the 94th 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 St. Tammany Parish higher risk than average?
St. Tammany Parish's composite risk score of 97th percentile is above the Louisiana state average of 62th percentile. This elevated risk is driven by hurricane exposure (99th percentile), along with flooding and wildfire and tornado and earthquake 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.