St. Louis County, Missouri: Natural Disaster Risk and History
St. Louis County, Missouri has a Relatively High natural-hazard risk rating in FEMA's National Risk Index (v1.20, December 2025): a score of 99.3 out of 100, higher than about 99% of US counties, with heat waves, hail and lightning scoring highest of its 18 hazards and $753 million a year in expected losses.
OpenFEMA lists 32 federal disaster declarations that included St. Louis County since 1973, not counting 2 for COVID-19; the latest is DR-4877-MO (Severe Storms, Straight-Line Winds, Tornadoes, and Flooding, declared 9 June 2025). NOAA's Storm Prediction Center recorded 48 tornadoes touching St. Louis County from 1950 to 2025.
Live weather alerts for Missouri All official warnings Latest FEMA declarations
Population 1,003,734 Buildings worth $264 billion Area 529 sq mi Risk rank in Missouri 1 of 115 FIPS 29189
All 18 hazards, highest risk first
FEMA National Risk Index| Hazard | Risk rating | Score | Expected loss a year | How often | Events in record |
|---|---|---|---|---|---|
| Heat wave | Very High | 99.9 | $253 million | about 15 a year | 153 |
| Hail | Very High | 99.7 | $38 million | about 5.3 a year | 200 |
| Lightning | Very High | 99.3 | $5.5 million | about 53 a year | 837,163 strikes |
| Inland flooding | Relatively High | 99.1 | $240 million | about 2.8 a year | 78 |
| Cold wave | Very High | 99.1 | $41 million | about 1.7 a year | 33 |
| Earthquake | Relatively High | 99.0 | $141 million | about once every 185 years | — |
| Ice storm | Very High | 98.8 | $3.8 million | about 1.4 a year | 95 |
| Winter weather | Very High | 98.3 | $1.5 million | about 8.7 a year | 166 |
| Tornado | Relatively High | 98.1 | $26 million | about once every 2.5 years | 37 |
| Landslide | Relatively Moderate | 97.6 | $442,557 | about once a year | — |
| Strong wind | Relatively High | 89.8 | $2.2 million | about 5.9 a year | 226 |
| Wildfire | Very Low | 61.7 | $100,748 | rarer than once in 1,000 years | — |
| Hurricane | Very Low | 45.1 | $48,380 | about once every 90 years | 2 |
| Drought | Very Low | 27.8 | $19,566 | about 1.9 a year | 56 |
| Avalanche | Not Applicable | — | — | — | — |
| Coastal flooding | Not Applicable | — | — | — | — |
| Tsunami | Not Applicable | — | — | — | — |
| 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 32
Most common: Severe Storm 16, Flood 10, Severe Ice Storm 3, Hurricane 1.
| Decade | Declarations | Incident types |
|---|---|---|
| 1970s | 3 | Tornado, Drought, Severe Storm |
| 1980s | 2 | Flood ×2 |
| 1990s | 6 | Severe Storm ×4, Flood ×2 |
| 2000s | 11 | Severe Storm ×6, Severe Ice Storm ×3, Hurricane, Flood |
| 2010s | 7 | Flood ×4, Severe Storm ×3 |
| 2020s | 3 | Severe Storm ×2, Flood |
The last 10
Widest declarations that included St. Louis County
- Severe Winter Storm (2011, EM-3317-MO): 115 Missouri counties designated.
- Severe Winter Storm (2009, EM-3303-MO): 115 Missouri counties designated.
- Severe Winter Storms (2007, EM-3281-MO): 115 Missouri counties designated.
Named storms in its declarations: Hurricane Katrina (2005).
Not counted above: 2 COVID-19 ("Biological") declarations — in 2020 every US county was included. Missouri also had 4 statewide declarations with no county list.
Tornado record since 1950 48
| Tornadoes touching the county | 48 |
|---|---|
| Strongest-rated | (E)F4 ×1 |
| Peak month | May (12) |
| Deadliest | 24 Jan 1967, F4, 25 mi path, 3 killed, 216 injured |
| Longest path | 31 May 2013, EF3, 31.7 mi path, 0 killed, 8 injured |
| Most recent | 4 Jun 2025, EF1, 6.8 mi path |
| Deaths / injuries on those paths | 6 / 257 |
| Rating | (E)F0 | (E)F1 | (E)F2 | (E)F3 | (E)F4 | (E)F5 | Unrated |
|---|---|---|---|---|---|---|---|
| Count | 12 | 21 | 9 | 5 | 1 | 0 | 0 |
| Decade | 1950s | 1960s | 1970s | 1980s | 1990s | 2000s | 2010s | 2020s |
|---|---|---|---|---|---|---|---|---|
| Count | 7 | 3 | 6 | 1 | 2 | 3 | 13 | 13 |
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. Louis County compares with its 5 nearest counties
| County | Distance | Overall risk | Score | Top hazard |
|---|---|---|---|---|
| St. Louis County (this page) | — | Relatively High | 99.3 | Heat wave |
| St. Louis City | 17 km | Relatively High | 98.7 | Heat wave |
| St. Charles County | 25 km | Relatively Moderate | 92.6 | Strong wind |
| Jefferson County | 43 km | Relatively Moderate | 90.5 | Strong wind |
| Monroe County, IL | 46 km | Very Low | 41.9 | Heat wave |
| St. Clair County, IL | 49 km | Relatively High | 94.9 | Heat wave |
Nearest by distance between county centres. Every county in Missouri, ranked.
Vulnerability and resilience
| Social vulnerability | Relatively Low 31.2 |
|---|---|
| Community resilience | Relatively High 79.7 |
| Community risk factor | 0.98 |
| Expected annual loss, all hazards | $753 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. Louis County's main hazards
- Right now: National Weather Service alerts for Missouri · all official warnings on Global Incident Tracker.
- Heat wave: Heatstroke warning signs
- Hail: Weather alerts for Missouri
- Lightning: Weather alerts for Missouri
- 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. Louis County
What natural disasters is St. Louis County, Missouri most at risk from?
St. Louis County, Missouri has a Relatively High natural-hazard risk rating in FEMA's National Risk Index (v1.20, December 2025): a score of 99.3 out of 100, higher than about 99% of US counties, with heat waves, hail and lightning scoring highest of its 18 hazards and $753 million a year in expected losses.
How many federal disaster declarations has St. Louis County had?
OpenFEMA lists 32 federal disaster declarations that included St. Louis County since 1973, not counting 2 for COVID-19; the latest is DR-4877-MO (Severe Storms, Straight-Line Winds, Tornadoes, and Flooding, declared 9 June 2025). Another 4 Missouri declarations were made statewide without a county list.
How many tornadoes have hit St. Louis County?
NOAA's Storm Prediction Center recorded 48 tornadoes touching St. Louis County from 1950 to 2025. The deadliest: 24 Jan 1967, F4, 25 mi path, 3 killed, 216 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.