FloodZoneMap.org

Washington County, Missouri Flood Zones

Check an Address in Washington County

Enter any address in Washington County, Missouri to see its FEMA flood zone

The Flooding Character of Washington County

Flash flooding from heavy rainfall is the primary flood hazard in Washington County, MO. Over the past 30 years, NOAA Storm Events data shows 24 recorded flash flood events compared to 2 general flood events. Recent examples include a flash flood event on April 4, 2025, which caused impassable roads due to heavy rainfall, and another on July 16, 2021, where training storms dropped up to four inches of rain in a short period, leading to several flash flood reports.

National Flood Insurance Program (NFIP) claims data indicates that properties designated as Zone A have experienced the most claims, with an average payout of $5,897 and an average water depth of 0.7 feet. While fewer claims have been filed in Zone X, these also show an average water depth of 0.5 feet. Homeowners in areas mapped as Zone A, or those located near creeks and streams that could experience rapid rises in water levels, should pay particular attention to flood risk.

Summary generated from NOAA storm narratives and NFIP claim data for this county. Not predictive.

Read First-Hand Flood Stories from Washington County

5 NOAA storm reports from this county describe what happened, in the words of the meteorologists who were there.

Read Missouri flood stories →

Flood Risk Data for Washington County

Washington County, Missouri has recorded 26 flood-related events since 1996 according to NOAA's Storm Events Database, including 24 flash floods and 2 river or area floods. The county has received 27 federal disaster declarations, 5 of which involved flooding or coastal storms. Enter any address above to check its FEMA flood zone designation.

Washington County Disaster History

FEMA Disaster Declarations (1973–2025)

Disaster Declarations
27
Flood/Coastal Disasters
5
Latest Disaster
Severe Storms, Straight-line Winds, Tornadoes, And Flooding (2025-04-29)

Source: OpenFEMA Disaster Declarations Summaries.

Recent Disaster Declarations in Washington County

DeclarationTypeDate
Severe Storms, Straight-line Winds, Tornadoes, And FloodingSevere StormApr 29, 2025
Severe Storms, Straight-line Winds, Tornadoes, And FloodingSevere StormMar 30, 2025
Severe Storms, Tornadoes, Straight-line Winds, And FloodingSevere StormNov 3, 2024
Covid-19BiologicalJan 20, 2020
Covid-19 PandemicBiologicalJan 20, 2020
Severe Storms, Tornadoes, Straight-line Winds And FloodingFloodApr 28, 2017
Severe Storms, Tornadoes, Straight-line Winds, And FloodingFloodDec 23, 2015
Severe Storms, Tornadoes, Straight-line Winds, And FloodingSevere StormMay 15, 2015
Severe Storms, Tornadoes, And FloodingSevere StormApr 19, 2011
Severe Winter StormSevere StormJan 31, 2011

Recorded Flood Events in Washington County

NOAA Storm Events Database (1996–2025)

Total Flood Events
26
River/Area Floods
2
Flash Floods
24
Flood Injuries
4

Source: NOAA National Weather Service Storm Events Database.

Recent Flood Events in Washington County

TypeDateDamage
Flash FloodApr 4, 20250.00K
Flash FloodNov 4, 20240.00K
Flash FloodApr 29, 20210.00K
Flash FloodJul 16, 20210.00K
Flash FloodApr 29, 20170.00K
Flash FloodAug 15, 20160.00K
Flash FloodMay 11, 20160.00K
FloodJun 16, 20150.00K
Flash FloodAug 10, 20150.00K
Flash FloodApr 8, 20150.00K

Washington County Flood History

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.

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...

Flash Flood — Apr 29, 2021

Southerly flow as well as intermittent showers and a few thunderstorms raised the dew point into the mid 60s to around 70 across the area. Also, forecast soundings showed a very moist and deep warm layer up to around 12,000 feet. This combined with strong 850mb moisture convergence across southern Missouri and Illinois and precipitable water values in the 99th plus percentile, set the region ...

Flash Flood — Jul 16, 2021

Training storms moved through portions of southeast Missouri and southwestern Illinois with up to 4 inches of rain in a short amount of time. There were several reports of flash flooding.

Flash Flood — Apr 29, 2017

A strong spring storm system brought multiple rounds of thunderstorms and heavy rain to the southeast half of Missouri during the weekend of April 29th-30th. Rainfall totals surpassed nine inches in some locations and this led to flash flooding and historic flooding along some of the tributaries of the Missouri and Mississippi Rivers. Areas along the Meramec River were especially hard hit as n...

Source: NOAA National Weather Service Storm Events Database.

Washington County NFIP Flood Insurance Claims

Total Claims Filed
32
Total Paid Out
$175,764
Avg Claim
$7,030
Avg Water Depth
3.5 ft

Claims by Flood Zone

A Zones (High Risk)
27
X Unshaded (Low)
1

Source: OpenFEMA NFIP Individual Claims (2.25M records analyzed).

Flood Zone Types in Washington County

FEMA assigns flood zone designations to areas in Washington 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.

View all flood zone types →

Flood Insurance in Washington County

Properties in Washington 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.