St. Tammany Parish, Louisiana: Natural Disaster Risk and History
St. Tammany Parish, Louisiana has a Relatively High natural-hazard risk rating in FEMA's National Risk Index (v1.20, December 2025): a score of 96.6 out of 100, higher than about 96% of US counties, with hurricanes, heat waves and lightning scoring highest of its 18 hazards and $249 million a year in expected losses.
OpenFEMA lists 48 federal disaster declarations that included St. Tammany Parish since 1965, not counting 2 for COVID-19; the latest is DR-4927-LA (Tropical Storm Arthur, declared 30 June 2026). NOAA's Storm Prediction Center recorded 72 tornadoes touching St. Tammany Parish from 1950 to 2025.
Live weather alerts for Louisiana All official warnings Latest FEMA declarations
Population 263,870 Buildings worth $49 billion Area 1,107 sq mi Risk rank in Louisiana 4 of 64 FIPS 22103
All 18 hazards, highest risk first
FEMA National Risk Index| Hazard | Risk rating | Score | Expected loss a year | How often | Events in record |
|---|---|---|---|---|---|
| Hurricane | Very High | 98.9 | $143 million | about once every 4.4 years | 83 |
| Heat wave | Relatively Moderate | 96.3 | $8.4 million | about 16 a year | 260 |
| Lightning | Relatively High | 95.7 | $2.1 million | about 85 a year | 525,688 strikes |
| Inland flooding | Relatively High | 94.2 | $70 million | about 2.3 a year | 65 |
| Cold wave | Relatively High | 92.7 | $9.2 million | about 1.1 a year | 20 |
| Wildfire | Relatively Moderate | 89.6 | $1.4 million | about once every 282 years | — |
| Hail | Relatively Moderate | 88.0 | $1.6 million | about 2 a year | 75 |
| Tornado | Relatively Moderate | 86.6 | $6.0 million | about once a year | 52 |
| Coastal flooding | Relatively High | 82.6 | $3.3 million | about 3.7 a year | — |
| Strong wind | Relatively Moderate | 80.9 | $1.4 million | about 1.6 a year | 50 |
| Drought | Relatively Moderate | 80.2 | $988,492 | about 19 a year | 742 |
| Winter weather | Relatively Moderate | 79.0 | $208,332 | about 1.1 a year | 20 |
| Ice storm | Relatively Moderate | 78.1 | $369,707 | about once every 1.9 years | 29 |
| Earthquake | Relatively Low | 67.3 | $724,477 | rarer than once in 1,000 years | — |
| Landslide | Very Low | 37.9 | $596 | about once every 8.2 years | — |
| Avalanche | Not Applicable | — | — | — | — |
| Tsunami | Insufficient Data | — | — | — | — |
| Volcanic activity | Not Applicable | — | — | — | — |
Score: FEMA's percentile among US counties that face the hazard (higher = more risk). Expected loss: FEMA's modelled average yearly loss to buildings, people (as a statistical value) and crops. How often: FEMA's annualised frequency of the hazard in the county; for some hazards it counts event-days, so it is a rough guide, not a forecast. "Not Applicable" means FEMA does not model that hazard here.
Federal disaster declarations 48
Most common: Hurricane 29, Flood 7, Coastal Storm 4, Severe Ice Storm 2.
| Decade | Declarations | Incident types |
|---|---|---|
| 1960s | 2 | Hurricane ×2 |
| 1970s | 3 | Flood ×2, Snowstorm |
| 1980s | 3 | Flood ×2, Hurricane |
| 1990s | 5 | Hurricane ×2, Severe Storm ×2, Flood |
| 2000s | 12 | Hurricane ×10, Other, Coastal Storm |
| 2010s | 6 | Hurricane ×3, Flood ×2, Coastal Storm |
| 2020s | 17 | Hurricane ×11, Coastal Storm ×2, Severe Ice Storm ×2, Tropical Storm, Winter Storm |
The last 10
Widest declarations that included St. Tammany Parish
- Severe Winter Storm (2026, EM-3638-LA): 64 Louisiana counties designated.
- Tropical Storm Francine (2024, EM-3614-LA): 64 Louisiana counties designated.
- Tropical Storm Nicholas (2021, EM-3574-LA): 64 Louisiana counties designated.
Named storms in its declarations: Tropical Storm Arthur (2026), Hurricane Francine (2024), Tropical Storm Francine (2024), Tropical Storm Nicholas (2021), Hurricane Ida (2021), Tropical Storm Ida (2021), Hurricane Zeta (2021), Tropical Storm Zeta (2020), Hurricane Delta (2020), Hurricane Sally (2020), Hurricane Laura (2020), Tropical Storm Cristobal (2020), Tropical Storm Barry (2019), Tropical Storm Nate (2017), Hurricane Isaac (2012), Tropical Storm Isaac (2012), Hurricane Ike (2008), Hurricane Gustav (2008), Hurricane Rita (2005), Hurricane Katrina (2005), Hurricane Ivan (2004), Hurricane Lili (2002), Tropical Storm Isidore (2002), Tropical Storm Allison (2001), Hurricane Georges (1998), Hurricane Andrew (1992), Hurricane Juan (1985), Hurricane Camille (1969), Hurricane Betsy (1965).
Not counted above: 2 COVID-19 ("Biological") declarations — in 2020 every US county was included. Louisiana also had 6 statewide declarations with no county list.
Tornado record since 1950 72
| Tornadoes touching the county | 72 |
|---|---|
| Strongest-rated | (E)F3 ×1 |
| Peak month | April (13) |
| Deadliest | 21 Nov 1997, F2, 9 mi path, 0 killed, 43 injured |
| Longest path | 7 Feb 2017, EF2, 23.1 mi path, 0 killed, 3 injured |
| Most recent | 15 Mar 2025, EF1, 7.7 mi path |
| Deaths / injuries on those paths | 0 / 58 |
| Rating | (E)F0 | (E)F1 | (E)F2 | (E)F3 | (E)F4 | (E)F5 | Unrated |
|---|---|---|---|---|---|---|---|
| Count | 34 | 29 | 8 | 1 | 0 | 0 | 0 |
| Decade | 1950s | 1960s | 1970s | 1980s | 1990s | 2000s | 2010s | 2020s |
|---|---|---|---|---|---|---|---|---|
| Count | 1 | 2 | 3 | 8 | 9 | 13 | 15 | 21 |
Deaths and injuries are for each tornado's whole path, which can run beyond this county. F-scale ratings before February 2007, Enhanced Fujita (EF) after.
How St. Tammany Parish compares with its 5 nearest counties
| County | Distance | Overall risk | Score | Top hazard |
|---|---|---|---|---|
| St. Tammany Parish (this page) | — | Relatively High | 96.6 | Hurricane |
| Hancock County, MS | 43 km | Relatively Moderate | 82.7 | Hurricane |
| Orleans Parish | 46 km | Relatively High | 98.3 | Hurricane |
| Washington Parish | 46 km | Relatively Moderate | 85.5 | Hurricane |
| Pearl River County, MS | 49 km | Relatively Moderate | 86.1 | Hurricane |
| Tangipahoa Parish | 50 km | Relatively Moderate | 93.3 | Hurricane |
Nearest by distance between county centres. Every county in Louisiana, ranked.
Vulnerability and resilience
| Social vulnerability | Relatively Low 34.0 |
|---|---|
| Community resilience | Very High 93.8 |
| Community risk factor | 0.99 |
| Expected annual loss, all hazards | $249 million |
FEMA scales expected losses up where social vulnerability is high (people who may find it harder to prepare, evacuate or recover) and down where community resilience is high. A factor above 1 raises the risk score. For social vulnerability a high rating is worse; for resilience a high rating is better.
Prepare for St. Tammany Parish's main hazards
- Right now: National Weather Service alerts for Louisiana · all official warnings on Global Incident Tracker.
- Hurricane: Is there a hurricane now? · Cyclone preparation
- Heat wave: Heatstroke warning signs
- Lightning: Weather alerts for Louisiana
- Your property's flood zone: FEMA Flood Map Service Center ↗ — this page cannot tell you that.
- Official preparedness guidance: Ready.gov ↗ and your county emergency management office.
What this page shows, and what it misses
FEMA's National Risk Index rates a whole county against every other US county; it is a planning-level estimate for nationwide comparison, not a flood-zone map and not a substitute for a local risk assessment or the risk to one home. Declarations are presidential disaster, emergency and fire management declarations that named this county; state declarations and SBA or USDA designations are not included. Tornadoes are counted when the county is one of up to four listed on the track; 670 tornadoes that crossed a state line carry no county list in NOAA's file and are left out.
Federal Emergency Management Agency (FEMA), National Risk Index Dataset: National Risk Index Counties - v1.20.0 (December 2025). Retrieved from https://services.arcgis.com/XG15cJAlne2vxtgt/ArcGIS/rest/services/National_Risk_Index_Counties/FeatureServer/0/query on November 2, 2026, 1:20 PM EST. This product uses the Federal Emergency Management Agency’s National Risk Index dataset API or downloadable datasets but is not endorsed by FEMA. The Federal Government or FEMA cannot vouch for the data or analyses derived from these data after the data have been retrieved from the Agency's website(s).
Federal Emergency Management Agency (FEMA), OpenFEMA Dataset: Disaster Declarations Summaries - v2, retrieved from https://www.fema.gov/api/open/v2/DisasterDeclarationsSummaries on November 2, 2026, 1:21 PM EST. This product uses the Federal Emergency Management Agency's OpenFEMA API, but is not endorsed by FEMA. The Federal Government or FEMA cannot vouch for the data or analyses derived from these data after the data have been retrieved from the Agency's website(s).
Tornado records: NOAA/NWS Storm Prediction Center, Severe Weather Database, tornadoes 1950–2025 (https://www.spc.noaa.gov/wcm/data/1950-2025_actual_tornadoes.csv, downloaded 2 November 2026). Public domain; not endorsed by NOAA. Compiled by Global Incident Tracker.
Questions about St. Tammany Parish
What natural disasters is St. Tammany Parish, Louisiana most at risk from?
St. Tammany Parish, Louisiana has a Relatively High natural-hazard risk rating in FEMA's National Risk Index (v1.20, December 2025): a score of 96.6 out of 100, higher than about 96% of US counties, with hurricanes, heat waves and lightning scoring highest of its 18 hazards and $249 million a year in expected losses.
How many federal disaster declarations has St. Tammany Parish had?
OpenFEMA lists 48 federal disaster declarations that included St. Tammany Parish since 1965, not counting 2 for COVID-19; the latest is DR-4927-LA (Tropical Storm Arthur, declared 30 June 2026). Another 6 Louisiana declarations were made statewide without a county list.
How many tornadoes have hit St. Tammany Parish?
NOAA's Storm Prediction Center recorded 72 tornadoes touching St. Tammany Parish from 1950 to 2025. The deadliest: 21 Nov 1997, F2, 9 mi path, 0 killed, 43 injured (deaths and injuries are for the whole path).
Is the National Risk Index a flood zone map?
No. The National Risk Index is a planning-level estimate for a whole county, built for nationwide comparison. It does not tell you the flood zone or the risk of a single property: for that, look up the address on FEMA's Flood Map Service Center (msc.fema.gov) and ask your local floodplain manager.