FloodZoneMap.org

Rock County, Wisconsin Flood Zones

Check an Address in Rock County

Enter any address in Rock County, Wisconsin to see its FEMA flood zone

The Flooding Character of Rock County

Flash flooding from heavy rainfall events is the dominant flood character in Rock County. Between 1993 and 2023, NOAA Storm Events data recorded 62 flood events and 23 flash flood events. For example, in June 2024, severe thunderstorms produced multiple reports of flash flooding across the county, including near Argyle and Janesville. Earlier, in June 2024, 4-6 inches of rain led to flash flooding in Rock and Walworth Counties.

NFIP claims data indicates that properties in Zone A and Zone X_UNSHADED have experienced the most significant flood damage. Zone A claims averaged $16,202 with an average water depth of 6.9 feet, while Zone X_UNSHADED claims averaged $12,029 with an average water depth of 9.1 feet. Homeowners in these zones, as well as those in Zone X_SHADED and Zone X, should pay close 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 Rock County

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

Read Wisconsin flood stories →

Flood Risk Data for Rock County

Rock County, Wisconsin has recorded 85 flood-related events since 1996 according to NOAA's Storm Events Database, including 23 flash floods and 62 river or area floods. The county has received 15 federal disaster declarations, 2 of which involved flooding or coastal storms. Enter any address above to check its FEMA flood zone designation.

Rock County Disaster History

FEMA Disaster Declarations (1973–2020)

Disaster Declarations
15
Flood/Coastal Disasters
2
Latest Disaster
Covid-19 Pandemic (2020-01-20)

Source: OpenFEMA Disaster Declarations Summaries.

Recent Disaster Declarations in Rock County

DeclarationTypeDate
Covid-19BiologicalJan 20, 2020
Covid-19 PandemicBiologicalJan 20, 2020
Severe Storms, Tornadoes, And FloodingSevere StormJun 5, 2008
Record Snow And Near Record SnowSnowstormFeb 5, 2008
Severe Storms And FloodingSevere StormAug 18, 2007
Hurricane Katrina EvacuationHurricaneAug 29, 2005
Severe Storms And FloodingSevere StormMay 7, 2004
SnowSnowstormDec 11, 2000
Severe Storms And FloodingSevere StormAug 5, 1998
Severe Storms, Tornadoes & FloodingSevere StormJun 7, 1993

Recorded Flood Events in Rock County

NOAA Storm Events Database (1996–2025)

Total Flood Events
85
River/Area Floods
62
Flash Floods
23
Total Property Damage
$33.6M
Flood Injuries
3

Source: NOAA National Weather Service Storm Events Database.

Recent Flood Events in Rock County

TypeDateDamage
FloodJun 29, 20251.00K
Flash FloodJun 18, 20255.00K
Flash FloodAug 18, 202550.00K
Flash FloodJun 22, 202420.00K
FloodJul 15, 20241.00K
FloodJul 14, 20241.00K
FloodJul 14, 20242.00K
Flash FloodJun 3, 202415.00K
FloodJun 3, 20241.00K
FloodApr 3, 20242.00K

Rock County Flood History

Flood — Jun 29, 2025

Numerous thunderstorms erupted over southern WI ahead of a slow moving cold front. Damaging downburst winds occurred in and around Timmerman Field in Milwaukee. Urban and small stream flooding occurred in Pardeeville and Janesville.

Flash Flood — Jun 18, 2025

Low pressure tracking from northern Missouri to southern Lake MI spread rounds of thunderstorms across far southern WI. This eventually led to flash flooding in Rock and Walworth Counties after 4-6 inches of rain had fallen.

Flash Flood — Aug 18, 2025

Numerous thunderstorms and heavy rain ahead of a slow moving cold front caused some flooding in southern Rock and Walworth Counties.

Flash Flood — Jun 22, 2024

Severe thunderstorms developed across western Wisconsin and moved eastward across southern Wisconsin through the afternoon and evening hours on June 22nd due to passing low pressure and its approaching cold front. There were supercell thunderstorms along with bowing segments along this line which lead to multiple areas of damage. Two strong tornadoes occurred, which were rated EF-2 near Argyl...

Flood — Jul 15, 2024

A complex of thunderstorms along a cold front moved across southern Wisconsin causing locally damaging winds, large hail and flash flooding. A tornado occurred near Evansville.

Source: NOAA National Weather Service Storm Events Database.

Rock County NFIP Flood Insurance Claims

Total Claims Filed
241
Total Paid Out
$3.1M
Avg Claim
$16,061
Avg Water Depth
11.6 ft

Claims by Flood Zone

A Zones (High Risk)
154
X Shaded (500-yr)
13
X Unshaded (Low)
22

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

Flood Zone Types in Rock County

FEMA assigns flood zone designations to areas in Rock County, Wisconsin:

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 Rock County

Properties in Rock County, Wisconsin 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.