26 flood insurance claims·$759,469 paid·7 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 Knox County, Nebraska. 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 dominates Knox County, accounting for 24 events alongside 17 flash flood occurrences over the last 30 years according to the NOAA Storm Events Database. Severe weather patterns drive these incidents, such as the June 21, 2024 series of training thunderstorms fueled by a stationary front, and the March 13, 2019 bomb cyclone. That historic 2019 event combined a 971mb low-pressure system with frozen ground, 15 inches of snow cover, and up to 2.5 inches of rain to generate widespread moderate to major flooding across the region.
National Flood Insurance Program records indicate that high-risk Zone A properties face the most severe impacts, logging 20 claims with an average payout of $45,720 and an average recorded water depth of 9 inches. Meanwhile, Zone X properties recorded 6 claims with an average payout of $23,877 and an average recorded water depth of 1 inch. Property owners situated within Zone A and those near rivers should pay the closest attention to these flood risks.
Summary written from NOAA storm reports and NFIP claims for this county. Not a prediction.
Less than 1% of Knox County’s flood insurance claims were on properties rated outside FEMA’s high-risk zones.
20 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 7 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 2011, with 12 claims and $598,832 paid, the year of 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.
19 NOAA storm reports from Knox County describe what happened, in the words of the forecasters who covered it. Read the Nebraska flood stories →
18 federal disaster declarations since 1967, 7 of them floods, coastal storms or hurricanes.
| Disaster | Began |
|---|---|
| Severe Storms And Straight-line Winds | May 12, 2022 |
| Severe Winter Storm, Straight-line Winds, And Flooding | Mar 9, 2019 |
| Severe Winter Storm And Straight-line Winds | Apr 13, 2018 |
| Flooding | Jun 17, 2011 |
| Flooding | May 24, 2011 |
| Severe Storms And Flooding | Jun 1, 2010 |
| Severe Winter Storms And Snowstorm | Dec 22, 2009 |
| Severe Storms, Flooding, And Tornadoes | May 4, 2007 |
Weather and water disasters only; most recent first. Source: OpenFEMA Disaster Declarations.
41 since 1996: 17 flash floods and 24 river or area floods.
| Event | Date | Damage |
|---|---|---|
| Flood | Jun 21, 2024 | $10,000 |
| Flash Flood | Aug 31, 2021 | — |
| Flood | Mar 13, 2019 | — |
| Flood | Mar 13, 2019 | $1.2M |
| Flash Flood | Aug 15, 2017 | $30,000 |
| Flood | Feb 14, 2017 | — |
| Flash Flood | Aug 21, 2013 | — |
| Flood | May 26, 2011 | $25,000 |
— = no damage estimate in the record. Source: NOAA Storm Events Database.
Flood · Jun 21, 2024. A series of shortwave troughs traversing the northern CONUS brought unsettled weather to the area for the end of June. On the 21st, a stationary front was draped across northeast Nebraska into Iowa. Ahead of one of the aforementioned shortwave troughs, several rounds of strong thunderstorms developed near this frontal zone and moved across northeast Nebraska. At 8 pm on the 21st, radar imagery showed training thun…
Flash Flood · Aug 31, 2021. Theta-e advection and a stationery front helped initiate storms across eastern Nebraska. The largest hail reports were for 2.5 inch hail and peak wind gusts were near 70 mph. Additionally, flash flooding was reported in Cedar County due to heavy precipitation.
Flood · Mar 13, 2019. A 971mb bomb cyclone moved out of the central Rockies on Wednesday, March 13, 2019 and helped to create widespread, moderate to major, and in many cases historic, flooding across eastern Nebraska and western Iowa. From 4 to 15 inches of snow cover remained across the mid Missouri River valley, and the ground was frozen with existing frost depths of 15 to 23 inches. Warm temperatures allowed all of the snow to rapi…
Flash Flood · Aug 15, 2017. Heavy rainfall fell on August 15th-16th The heaviest rains were focused over western Butler and Polk counties. A cooperative weather observer in David City measured 6.01 inches of rain for this event. This rain caused the Big Blue River and nearby tributaries to reach flood stage, which lasted until 8/23. Many roads were flooded and closed for several days in the affected area. Highway 30 was flooded near Rich…
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 Knox 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.