46
Recorded events
0
Direct deaths
0
Direct injuries
$8.0M
Property damage
Flood in Winnebago County, Illinois: 46 recorded events between 2006 and 2026. The strongest on record measured 0. That places the county #275 nationally and #14 statewide for this hazard.
Decade by decade
Flood in Winnebago County, Illinois: events per decade
Reporting practice changed over time — early decades are undercounted, not calmer.
The busiest decade for flood in Winnebago County is the 2010s, when 25 of the county's 46 recorded events were logged. Comparing decades is useful for spotting active periods, but the earliest years are thin because systematic reporting for this hazard began later.
Within the Winnebago County archive, flood makes up 6.6% of all recorded severe weather across 8 hazard types. Nationally the county sits at #275 for this hazard and #14 within Illinois, putting it in the 90.7 percentile of all U.S. counties.
Seasonality
Events by month
Jul is the peak month for flood in Winnebago County with 13 recorded events, while Jan is the quietest. Seasonality here is a property of the archive as much as the climate: reports cluster where population and spotter networks are densest.
Most recent
Latest recorded events
| Date | Location | Magnitude | Damage |
|---|---|---|---|
| Apr 14, 2026 | ROCKFORD | — | $0 |
| Jul 26, 2025 | NEW MILFORD | 0 | $0 |
| Jun 18, 2025 | ROCKFORD | 0 | $0 |
| Jun 18, 2025 | ROCKFORD | 0 | $0 |
| Jul 16, 2024 | CHERRY VALLEY | 0 | $0 |
| Jul 15, 2024 | WEMPLETON | 0 | $0 |
| Jul 15, 2024 | WINNEBAGO | 0 | $0 |
| Jul 14, 2024 | WOODCREST | 0 | $0 |
| May 7, 2024 | MACHESNEY PARK | 0 | $0 |
| Aug 9, 2021 | (RFD) ROCKFORD AIRPORT | 0 | $0 |
Other hazards here
More from Winnebago County
- Thunderstorm Wind 342
- Hail 215
From the record
What the reports say
Written by National Weather Service staff at the time of the event · public domain
Major river flooding occurred along portions of the Pecatonica and Rock Rivers during the middle of March. For the Pecatonica River near Shirland, the river crested at 16.45 feet on March 17th. Moderate flood stage is 14 feet and major flood stage is 15.5 feet. For the Rock River at Rockton, the river crested at 14.09 feet on March 17th. Moderate flood stage is 11 feet and major flood stage is 14 feet. This crest of 14.09 feet was the fourth highest crest on record at Rockton. For the Rock River at Latham Park, the river crested at 14.44 feet on March 17th. Moderate flood stage is 11 feet and major flood stage is 13.5 feet. This crest of 14.44 feet was the second highest crest on record at Latham Park. An estimated 700 homes were impacted by flood waters from the Rock River.
Standing water up to 6 inches deep was reported in streets. Vehicles were stranded in deep standing water on Charles Street near 9th Street, East State Street near Rockford Avenue, and at East State Street and New Towne Drive.
Flowing water was reported up to curbs along parts of Harrison Avenue. Flooding was reported at the intersection of Sandy Hollow and Alpine Roads. Flooding was also reported along 11th Street between Sandy Hollow Road and Harrison Avenue.
Quick answers
Frequently asked
How many flood events are on record in Winnebago County, Illinois?
46 flood events are recorded in Winnebago County between 2006 and 2026, causing 0 direct deaths.
What is the strongest flood recorded in Winnebago County?
The strongest flood on record in Winnebago County measured 0.
Where does the flood data for Winnebago County come from?
All events come from the NOAA/NCEI Storm Events Database, the federal public-domain archive of severe weather reports. Dates are UTC, damage is as reported and not inflation-adjusted, and the most recent entries may still be revised.
Cite this page
“Flood in Winnebago County, Illinois.” Severe Weather History. severeweatherhistory.com/county/illinois/winnebago-county/flood/ · Data: NOAA/NCEI, FEMA, U.S. Census — public domain.