Enter any address in St. Louis County, Missouri to see its FEMA flood zone
Flash flooding from intense thunderstorms is the dominant flood character in St. Louis County. Between 1996 and 2023, NOAA Storm Events data recorded 68 flash flood events, resulting in 7 fatalities, alongside 21 other flood events. For example, on August 10, 2025, slow-moving thunderstorms produced flash flooding that made several interstates impassable. Earlier that year, on April 4 and 5, 2025, a stationary front caused widespread flooding, rendering numerous roads impassable across the metropolitan area.
National Flood Insurance Program (NFIP) claims data indicates that properties in Zone A, which have a high number of claims (7841), experienced an average water depth of 4.7 feet and an average payout of $23,369. Properties in Zone X, though fewer in number (653 claims), saw the highest average payout ($32,844) and an average water depth of 5.5 feet. Homeowners in Zone A and Zone X, as well as those in areas with unknown flood risk, should pay particular attention to their flood risk.
Summary generated from NOAA storm narratives and NFIP claim data for this county. Not predictive.
22 NOAA storm reports from this county describe what happened, in the words of the meteorologists who were there.
St. Louis County, Missouri has recorded 89 flood-related events since 1996 according to NOAA's Storm Events Database, including 68 flash floods and 21 river or area floods. The county has received 34 federal disaster declarations, 10 of which involved flooding or coastal storms. Enter any address above to check its FEMA flood zone designation.
FEMA Disaster Declarations (1973–2025)
Source: OpenFEMA Disaster Declarations Summaries.
| Declaration | Type | Date |
|---|---|---|
| Severe Storms, Straight-line Winds, Tornadoes, And Flooding | Severe Storm | May 16, 2025 |
| Severe Storms, Straight-line Winds, Tornadoes, And Wildfires | Severe Storm | Mar 14, 2025 |
| Severe Storms And Flooding | Flood | Jul 25, 2022 |
| Covid-19 | Biological | Jan 20, 2020 |
| Covid-19 Pandemic | Biological | Jan 20, 2020 |
| Severe Storms, Tornadoes, Straight-line Winds And Flooding | Flood | Apr 28, 2017 |
| Severe Storms, Tornadoes, Straight-line Winds, And Flooding | Flood | Dec 23, 2015 |
| Severe Storms, Straight-line Winds, Tornadoes, And Flooding | Severe Storm | May 29, 2013 |
| Flooding | Flood | Jun 1, 2011 |
| Severe Storms, Tornadoes, And Flooding | Severe Storm | Apr 19, 2011 |
NOAA Storm Events Database (1996–2025)
Source: NOAA National Weather Service Storm Events Database.
| Type | Date | Damage |
|---|---|---|
| Flash Flood | Aug 10, 2025 | 1.00K |
| Flood | Apr 5, 2025 | 200.00K |
| Flash Flood | Apr 4, 2025 | 30.00K |
| Flood | Apr 4, 2025 | 0.00K |
| Flash Flood | Nov 4, 2024 | 200.00K (2 deaths) |
| Flood | Nov 4, 2024 | 50.00K |
| Flash Flood | Apr 2, 2024 | 1.00K |
| Flash Flood | Jul 17, 2023 | 0.00K |
| Flash Flood | Apr 15, 2023 | 0.00K |
| Flash Flood | May 14, 2023 | 0.00K |
Flash Flood — Aug 10, 2025
Conditions were primed for flash flooding during the afternoon of August 10th. With very little wind shear, very high precipitable water values, and an area of moisture convergence, thunderstorms were able to develop and move very slowly as they poured out. This is what happened over the St. Louis metropolitan area. Flash flooding occurred as a result, with Interstates 44, 55, 64, 70, and 255 a...
Flood — Apr 5, 2025
A stationary front over southern Missouri along with ample mid-level forcing, moisture, and efficient rain processes resulted in flooding across portions of east-central and southeast Missouri. Numerous roads across the St. Louis metropolitan area were impassable due to the heavy rainfall.
Flash Flood — Apr 4, 2025
A stationary front over southern Missouri along with ample mid-level forcing, moisture, and efficient rain processes resulted in flooding across portions of east-central and southeast Missouri. Numerous roads across the St. Louis metropolitan area were impassable due to the heavy rainfall.
Flood — Apr 4, 2025
A stationary front over southern Missouri along with ample mid-level forcing, moisture, and efficient rain processes resulted in flooding across portions of east-central and southeast Missouri. Numerous roads across the St. Louis metropolitan area were impassable due to the heavy rainfall.
Flash Flood — Nov 4, 2024
Overnight on Sunday, November 3rd, a shield of rain and thunderstorms moved into the bi-state area. By Monday morning, persistent rainfall resulted in fatal flash flooding in southeast Missouri, with one fatality occurring in Iron County. Later on Monday evening, a QLCS produced two EF-0 tornadoes in east-central Missouri and shifted the axis of heaviest rain to the north. Due to the shift nort...
Source: NOAA National Weather Service Storm Events Database.
Source: OpenFEMA NFIP Individual Claims (2.25M records analyzed).
FEMA assigns flood zone designations to areas in St. Louis County, Missouri:
AE High Risk — 1% annual chance of flooding. Insurance required.
VE Very High Risk — Coastal flooding with wave action.
X (Shaded) Moderate Risk — 500-year floodplain.
X Low Risk — Outside major floodplains.
Properties in St. Louis County, Missouri that are in FEMA-designated Special Flood Hazard Areas (zones A and V) with federally backed mortgages are required to carry flood insurance.
Even outside high-risk zones, flood insurance is recommended. From 2014 to 2024, nearly one-third of NFIP claims came from outside the high-risk Special Flood Hazard Area.
Visit FloodSmart.gov to find an agent and get a quote.