503 flood insurance claims·$10.9M paid·2 federal flood & hurricane disasters
Share of the whole county outline, rivers and lakes included; parts FEMA hasn’t mapped count as zero.
Shaded areas are FEMA’s mapped flood hazard zones in and around Jefferson County, Wisconsin. Zoomed out they are simplified; at street level the map switches to FEMA’s exact layer. Tap anywhere to check that spot, or search an address above.
River flooding and flash flooding from heavy rainfall dominate the historical flood record in Jefferson County, which recorded 39 flood events and 16 flash flood events over the last 30 years according to the NOAA Storm Events Database. Recent events illustrate this pattern, such as a slow-moving warm front that brought heavy rainfall and flash flooding from June 3rd to June 4th, 2024, and already high river levels combined with additional heavy rainfall on June 22nd, 2024, that led to prolonged river flooding. Additionally, mild temperatures and rainfall in March 2019 caused snowmelt and excessive runoff over frozen ground, resulting in river flooding, atypical flooding from ice jams, community evacuations, and a response from the American Red Cross.
Property owners in mapped high-risk areas should pay the most attention to flood risk, as the National Flood Insurance Program data shows the vast majority of claims are concentrated in Zone A, with 440 claims averaging a payout of $25,537 and an average recorded water depth of 14 inches. However, properties outside designated high-risk zones also experience significant water intrusion, as evidenced by claims in Zone X, Zone X_UNSHADED, Zone X_SHADED, and unknown zones, where average payouts ranged from $5,646 to $67,365 and average recorded water depths ranged from 2 to 27 inches.
Summary written from NOAA storm reports and NFIP claims for this county. Not a prediction.
5% of Jefferson County’s flood insurance claims were on properties rated outside FEMA’s high-risk zones.
465 NFIP claims with a recorded rated flood zone, 1978 to date. The zone is the one FEMA used to rate that policy, which may not match today’s map. Source: OpenFEMA NFIP claims.
In flood insurance claims here that reported a flood depth, the average was 14 inches.
Drawn to scale against an 80-inch door. Even a few inches soaks flooring, the bottom of the drywall and anything plugged in near the floor.
Average of the depths reported on claims (zero and implausible values left out); FEMA’s record doesn’t say exactly where each depth was measured. Source: OpenFEMA NFIP claims.
The worst year was 2008, with 210 claims and $8.9M paid, the year of Severe Storms, Tornadoes, and Flooding.
Bar height is scaled by square root so ordinary years stay visible next to the worst one. NFIP claims by year of loss. Source: OpenFEMA.
35 NOAA storm reports from Jefferson County describe what happened, in the words of the forecasters who covered it. Read the Wisconsin flood stories →
13 federal disaster declarations since 1965, 2 of them floods, coastal storms or hurricanes.
| Disaster | Began |
|---|---|
| Severe Storms, Tornadoes, And Flooding | Jun 5, 2008 |
| Record Snow And Near Record Snow | Feb 5, 2008 |
| Severe Storms And Flooding | Aug 18, 2007 |
| Hurricane Katrina Evacuation | Aug 29, 2005 |
| Severe Storms And Flooding | May 7, 2004 |
| Severe Storms, Tornadoes & Flooding | Jun 7, 1993 |
| Severe Storms & Hail | Jul 7, 1991 |
| Drought | Jun 17, 1976 |
Weather and water disasters only; most recent first. Source: OpenFEMA Disaster Declarations.
55 since 1996: 16 flash floods and 39 river or area floods.
| Event | Date | Damage |
|---|---|---|
| Flood | Jun 25, 2024 | $1,000 |
| Flood | Jun 5, 2024 | $1,000 |
| Flood | Jul 4, 2024 | $1,000 |
| Flash Flood | Jun 3, 2024 | $5,000 |
| Flood | Jul 1, 2024 | $1,000 |
| Flood | Mar 17, 2019 | $10,000 |
| Flood | Mar 15, 2019 | $1,000 |
| Flood | Mar 14, 2019 | $10,000 |
— = no damage estimate in the record. Source: NOAA Storm Events Database.
Flood · Jun 25, 2024. Already high river levels, and additional heavy rainfall the evening of June 22nd, led to more river flooding late in June into July over portions of southern WI.
Flood · Jun 5, 2024. High river levels continued from May into June with additional rounds of heavy rainfall early in June leading to river flooding.
Flood · Jul 4, 2024. River flooding from late June continued into early July.
Flash Flood · Jun 3, 2024. A slow moving warm front brought multiple rounds of strong to severe thunderstorms and heavy rainfall from late morning on June 3rd into the early morning hours of June 4th. Areas of flooding did occur along with some wind damage.
National Weather Service narratives, lightly trimmed. Source: NOAA Storm Events Database.
Every colour on the map above is a place on this drawing: where the ground sits relative to the flood FEMA plans for.
If a building in Jefferson County is in a high-risk zone (A or V) and its mortgage comes from a federally regulated or insured lender, or is federally backed, flood insurance is required.
Outside those zones it is optional, and often worth having: from 2014 to 2024 nearly one-third of NFIP claims came from outside the high-risk Special Flood Hazard Area. Since Risk Rating 2.0, NFIP premiums are set for each building, so the only reliable price is a quote: FloodSmart.gov or a local agent.