Jefferson County, Missouri: Natural Disaster Risk and History
Jefferson County, Missouri has a Relatively Moderate natural-hazard risk rating in FEMA's National Risk Index (v1.20, December 2025): a score of 90.5 out of 100, higher than about 90% of US counties, with strong winds, landslides and tornadoes scoring highest of its 18 hazards and $114 million a year in expected losses.
OpenFEMA lists 28 federal disaster declarations that included Jefferson County since 1973, not counting 2 for COVID-19; the latest is DR-4867-MO (Severe Storms, Straight-Line Winds, Tornadoes, and Wildfires, declared 21 May 2025). NOAA's Storm Prediction Center recorded 44 tornadoes touching Jefferson County from 1950 to 2025.
Live weather alerts for Missouri All official warnings Latest FEMA declarations
Population 226,703 Buildings worth $39 billion Area 671 sq mi Risk rank in Missouri 5 of 115 FIPS 29099
All 18 hazards, highest risk first
FEMA National Risk Index| Hazard | Risk rating | Score | Expected loss a year | How often | Events in record |
|---|---|---|---|---|---|
| Strong wind | Very High | 98.6 | $8.7 million | about 5.6 a year | 213 |
| Landslide | Relatively Moderate | 95.9 | $223,548 | about 2.5 a year | — |
| Tornado | Relatively High | 95.1 | $16 million | about once every 2.1 years | 29 |
| Hail | Relatively Moderate | 93.9 | $3.2 million | about 5.2 a year | 196 |
| Earthquake | Relatively Moderate | 93.4 | $12 million | about once every 168 years | — |
| Heat wave | Relatively Moderate | 92.1 | $4.8 million | about 13 a year | 147 |
| Inland flooding | Relatively Moderate | 91.4 | $59 million | about 1.8 a year | 50 |
| Lightning | Relatively High | 91.2 | $1.7 million | about 54 a year | 255,875 strikes |
| Cold wave | Relatively Moderate | 88.9 | $8.3 million | about 1.4 a year | 26 |
| Winter weather | Relatively Moderate | 84.1 | $339,484 | about 8.6 a year | 164 |
| Ice storm | Relatively Moderate | 69.4 | $279,516 | about 1.2 a year | 80 |
| Wildfire | Very Low | 53.1 | $72,454 | rarer than once in 1,000 years | — |
| Hurricane | Very Low | 23.7 | $10,920 | about once every 65 years | 6 |
| Drought | Very Low | 22.3 | $8,905 | about 2.1 a year | 63 |
| 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 28
Most common: Severe Storm 16, Flood 7, Severe Ice Storm 2, Hurricane 1.
| Decade | Declarations | Incident types |
|---|---|---|
| 1970s | 3 | Tornado, Drought, Severe Storm |
| 1980s | 1 | Flood |
| 1990s | 5 | Severe Storm ×3, Flood ×2 |
| 2000s | 12 | Severe Storm ×8, Severe Ice Storm ×2, Hurricane, Flood |
| 2010s | 6 | Severe Storm ×3, Flood ×3 |
| 2020s | 1 | Severe Storm |
The last 10
Widest declarations that included Jefferson 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 44
| Tornadoes touching the county | 44 |
|---|---|
| Strongest-rated | (E)F3 ×2 |
| Peak month | April (12) |
| Deadliest | 31 Dec 2010, EF3, 6.7 mi path, 1 killed, 6 injured |
| Longest path | 14 Mar 2025, EF2, 25.3 mi path |
| Most recent | 7 Jun 2025, EF1, 4.9 mi path |
| Deaths / injuries on those paths | 2 / 10 |
| Rating | (E)F0 | (E)F1 | (E)F2 | (E)F3 | (E)F4 | (E)F5 | Unrated |
|---|---|---|---|---|---|---|---|
| Count | 14 | 22 | 5 | 2 | 0 | 0 | 1 |
| Decade | 1950s | 1960s | 1970s | 1980s | 1990s | 2000s | 2010s | 2020s |
|---|---|---|---|---|---|---|---|---|
| Count | 0 | 8 | 3 | 4 | 6 | 5 | 9 | 9 |
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 Jefferson County compares with its 5 nearest counties
| County | Distance | Overall risk | Score | Top hazard |
|---|---|---|---|---|
| Jefferson County (this page) | — | Relatively Moderate | 90.5 | Strong wind |
| Monroe County, IL | 32 km | Very Low | 41.9 | Heat wave |
| St. Louis County | 43 km | Relatively High | 99.3 | Heat wave |
| Washington County | 45 km | Relatively Low | 67.8 | Heat wave |
| St. Louis City | 49 km | Relatively High | 98.7 | Heat wave |
| Franklin County | 50 km | Relatively Moderate | 83.5 | Strong wind |
Nearest by distance between county centres. Every county in Missouri, ranked.
Vulnerability and resilience
| Social vulnerability | Very Low 12.2 |
|---|---|
| Community resilience | Relatively High 68.3 |
| Community risk factor | 0.80 |
| Expected annual loss, all hazards | $114 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 Jefferson County's main hazards
- Right now: National Weather Service alerts for Missouri · all official warnings on Global Incident Tracker.
- Strong wind: Power outages now
- Landslide: Landslides recorded
- Tornado: Is there a tornado warning now?
- 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 Jefferson County
What natural disasters is Jefferson County, Missouri most at risk from?
Jefferson County, Missouri has a Relatively Moderate natural-hazard risk rating in FEMA's National Risk Index (v1.20, December 2025): a score of 90.5 out of 100, higher than about 90% of US counties, with strong winds, landslides and tornadoes scoring highest of its 18 hazards and $114 million a year in expected losses.
How many federal disaster declarations has Jefferson County had?
OpenFEMA lists 28 federal disaster declarations that included Jefferson County since 1973, not counting 2 for COVID-19; the latest is DR-4867-MO (Severe Storms, Straight-Line Winds, Tornadoes, and Wildfires, declared 21 May 2025). Another 4 Missouri declarations were made statewide without a county list.
How many tornadoes have hit Jefferson County?
NOAA's Storm Prediction Center recorded 44 tornadoes touching Jefferson County from 1950 to 2025. The deadliest: 31 Dec 2010, EF3, 6.7 mi path, 1 killed, 6 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.