Headline:
Flood Warning issued April 23 at 9:33PM CDT by NWS Milwaukee/Sullivan WI
Event:
Flood Warning
Urgency:
Immediate
Effective:
April 23, 2026 - 7:33pm
Expires:
April 24, 2026 - 7:45am
Description:
...Forecast flooding changed to Moderate severity and increased in
duration for the following rivers in Wisconsin...
Rock River At Fort Atkinson affecting Jefferson County.
Rock River At Jefferson affecting Jefferson County.
Rock River At Watertown affecting Jefferson County.
Crawfish River At Milford affecting Jefferson County.
...The Flood Warning continues for the following rivers in
Wisconsin...Illinois...
Rock River At Newville affecting Rock County.
Rock River Near Lake Koshkonong affecting Rock and Jefferson
Counties.
Rock River At Afton affecting Rock and Winnebago Counties.
ROCK RIVER near LEBANON-3 E-HWY MM BRIDGE affecting Dodge County.
* WHAT...Moderate flooding is occurring and moderate flooding is
forecast.
* WHERE...Rock River near Lake Koshkonong.
* WHEN...Until further notice.
* IMPACTS...At 11.3 feet, There is knee-deep water over Blackhawk
Island Road. Lamp Road on west side of river also becomes flooded.
Lake Koshkonong merges with Mud Lake to the east of Lake
Koshkonong.
* ADDITIONAL DETAILS...
- At 9:00 PM CDT Thursday the stage was 11.4 feet.
- Bankfull stage is 9.0 feet.
- Recent Activity...The maximum river stage in the 24 hours
ending at 9:00 PM CDT Thursday was 11.4 feet.
- Forecast...The river is expected to remain in moderate flood
through the weekend.
- Flood stage is 10.0 feet.
- Flood History...This crest compares to a previous crest of
11.4 feet on 03/29/2009.
- http://www.weather.gov/safety/flood
Instruction:
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
Motorists should not attempt to drive around barricades or drive
cars through flooded areas.
Even 6 inches of fast-moving flood water can knock you off your feet
and a depth of 2 feet will float your car. Never try to walk, swim,
or drive through such swift water. If you come upon flood waters,
stop, turn around and go another way.
Caution is urged when walking near riverbanks.
Additional information is available at www.weather.gov.
The next statement will be issued Friday morning at 945 AM CDT.
Area Description:
Jefferson, WI; Rock, WI
Forcast Office:
NWS Milwaukee/Sullivan WI