St. Louis County, Missouri
Natural disaster risk, federal disaster history and flood insurance facts.
St. Louis County, Missouri has a relatively high overall risk from natural hazards in FEMA's National Risk Index. Its risk score is in the top 1% of US counties. It ranks 1st of 115 counties in Missouri. The costliest hazards here are heat waves, inland flooding and earthquakes. FEMA estimates about $753 million a year in expected losses, or roughly $750 per resident. Since 1973 it has been included in 32 federal disaster or emergency declarations for natural events (24 major disasters). The most recent was in June 2025 (severe storms, straight-line winds, tornadoes and flooding). Fewer than 1 in 100 homes here carry federal flood insurance (2,070 policies). Since 1978, federal flood insurance has paid about $264 million on 12,031 claims here.
FEMA National Risk Index December 2025; OpenFEMA declarations to Nov 6, 2026; NFIP records. Updated November 6, 2026.
Top risks in St. Louis County
- Check that cooling works before summer.
- Know where the nearest cooling center is.
- Check the FEMA flood map for your address, and ask the seller or landlord about past flooding.
- Price a flood policy now. Most new federal policies take 30 days to start.
- Ask whether an older house is bolted to its foundation.
- Consider separate earthquake insurance where risk is high.
All 18 hazards
What the ratings mean ›| Hazard | Rating | Score | Expected loss a year | |
|---|---|---|---|---|
| Heat wave | 99.9 | $253M | ||
| Inland flooding | 99.1 | $240M | ||
| Earthquake | 99.0 | $141M | ||
| Cold wave | 99.1 | $41M | ||
| Hail | 99.7 | $38M | ||
| Tornado | 98.1 | $26M | ||
| Lightning | 99.3 | $5M | ||
| Ice storm | 98.8 | $4M | ||
| Strong wind | 89.8 | $2M | ||
| Winter weather | 98.3 | $2M | ||
| Landslide | 97.6 | $443K | ||
| Wildfire | 61.7 | $101K | ||
| Hurricane | 45.1 | $48K | ||
| Drought | 27.8 | $20K |
Scores are percentiles: a score of 90 means higher risk than about 90% of US counties for that hazard. Hazards FEMA does not rate here are left out. Social vulnerability is relatively low and community resilience is relatively high in FEMA's measures.
Federal disaster history
Recent disasters nationwide ›Declarations by decade
Federal declarations for natural events that included St. Louis County. 2020s bar runs to November 2026.
By type
Most recent
Show all 32
Missouri also had 5 statewide declarations that did not name single counties.
Storm history since 1950
Tornado risk by county ›The National Weather Service has logged 1,464 storm reports in St. Louis County since 1950, with 29 deaths and 436 injuries and about $1.5 billion in reported damage. The strongest on record here was an F4 tornado on February 10, 1959.
Strongest tornadoes
| Date | Strength | Near | Hurt / killed |
|---|---|---|---|
| Feb 10, 1959 | F4 | – | 170 / 10 |
| Jan 24, 1967 | F4 | – | 216 / 3 |
| Apr 22, 2011 | EF4 | Vigus | 5 / 0 |
| Dec 31, 2010 | EF3 | St Louis Weiss Arpt | 6 / 1 |
| Jan 3, 1950 | F3 | – | 3 / 0 |
Most damaging storms
| Date | Type | Near | Damage |
|---|---|---|---|
| Apr 10, 2001 | Hail | Florissant | $400M |
| Apr 10, 2001 | Hail | Lambert Fld St | $300M |
| Apr 22, 2011 | Tornado | Vigus | $250M |
| Dec 27, 2015 | Flood | Allenton | $235M |
| Apr 10, 2001 | Hail | Bellefontaine Neighb | $100M |
| Jul 26, 2022 | Flash Flood | Spirit/St Louis | $50M |
Source: NOAA Storm Events Database, county-based reports through Jul 27, 2026. Tornado records start in 1950, hail and wind in 1955, and floods and other storm types in 1996, so older decades undercount. Damage is in dollars of the year it happened and is often an estimate. Winter storms, heat and hurricanes are logged by forecast zone, not county, so they are not counted here.
Flood insurance in St. Louis County
Check your address flood zone ›National Flood Insurance Program (NFIP) records only; private flood policies are not included. Home counts as of Aug 3, 2026. Since 2021 NFIP prices each home separately under Risk Rating 2.0, so your price depends on the building, not the county. Ask an agent for a quote.
Homes in St. Louis County
Older homes and mobile homes usually suffer more damage in storms, floods and earthquakes, and can cost more to insure. If you are buying, ask about roof age, foundation bolting and any retrofits. Source: US Census Bureau, American Community Survey 2020 to 2024 5-year estimates; 446,192 housing units.
Compare in Missouri
All 115 ›| Largest counties | Overall risk | Top hazard |
|---|---|---|
| St. Louis County | Heat wave | |
| Jackson County | Inland flooding | |
| St. Charles County | Inland flooding | |
| St. Louis City | Heat wave | |
| Greene County | Inland flooding | |
| Clay County | Inland flooding | |
| Jefferson County | Inland flooding | |
| Boone County | Inland flooding |
Neighboring counties
| County | Overall risk | Declarations |
|---|---|---|
| St. Charles County | 26 | |
| St. Louis City | 23 | |
| Madison County, IL | 14 | |
| St. Clair County, IL | 17 | |
| Jefferson County | 28 | |
| Franklin County | 22 | |
| Monroe County, IL | 18 |
Common questions about St. Louis County
What is the biggest natural hazard in St. Louis County?
Heat wave has the highest expected yearly losses in St. Louis County, about $253 million a year in FEMA's estimate. Inland flooding is second at $240 million.
How many federal disasters has St. Louis County had?
St. Louis County has been included in 32 federal disaster or emergency declarations for natural events since 1973, including 24 major disasters. The most recent was Severe Storms, Straight-Line Winds, Tornadoes, and Flooding in June 2025.
Is St. Louis County a high-risk place to live?
Its overall rating is Relatively High, 1st highest of 115 in Missouri. A county rating covers the whole area. Risk at one address can be much higher or lower, so check the FEMA flood map and ask about the home's history.
Do I need flood insurance in St. Louis County?
Standard home insurance does not cover flooding. About 1 in 167 homes in St. Louis County has federal flood insurance. Lenders require it in mapped high-risk zones, but many flood claims come from outside those zones.
How many tornadoes has St. Louis County had?
NOAA records list 58 tornadoes in St. Louis County since 1950. The strongest was an F4 tornado on February 10, 1959. The weather service has also logged 660 hail reports and 83 floods here.
Sources: FEMA National Risk Index (December 2025), OpenFEMA Disaster Declarations Summaries, and NFIP policy and claims data. Hazard Compass is independent and not affiliated with FEMA. These figures describe the whole county, not a single property, and are not insurance or safety advice. Report a problem.