Headline:
Flood Warning issued April 18 at 5:27AM CDT by NWS Milwaukee/Sullivan WI
Event:
Flood Warning
Urgency:
Immediate
Effective:
April 18, 2026 - 3:27am
Expires:
April 18, 2026 - 3:30pm
Description:
...The Flood Warning continues for the following rivers in
Wisconsin...Illinois...
Baraboo River Near Baraboo affecting Sauk and Columbia Counties.
Rock River At Fort Atkinson affecting Jefferson County.
Rock River At Afton affecting Rock and Winnebago Counties.
Rock River At Jefferson affecting Jefferson County.
Rock River At Watertown affecting Jefferson County.
ROCK RIVER near LEBANON-3 E-HWY MM BRIDGE affecting Dodge County.
Rock River Near Lake Koshkonong affecting Rock and Jefferson
Counties.
Fox River Near Berlin affecting Green Lake County.
Crawfish River At Milford affecting Jefferson County.
Fox River Lower At Waukesha affecting Waukesha County.
Fox River Lower Near New Munster affecting Kenosha and Lake
Counties.
Milwaukee River Near Cedarburg affecting Ozaukee County.
Pecatonica River At Martintown affecting Green County.
Root River Canal At Raymond affecting Racine County.
Turtle Creek Near Clinton affecting Rock and Winnebago Counties.
Wisconsin River At Portage affecting Columbia County.
...The Flood Warning is cancelled for the following rivers in
Wisconsin...
Wisconsin River At Wisconsin Dells affecting Sauk and Columbia
Counties.
* WHAT...Major flooding is forecast.
* WHERE...Rock River near Lake Koshkonong.
* WHEN...From this morning 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 4:00 AM CDT Saturday the stage was 9.9 feet.
- Bankfull stage is 9.0 feet.
- Forecast...The river is expected to rise above flood stage
this morning and continue rising to 12.1 feet Thursday
morning. Additional rises are possible thereafter.
- Flood stage is 10.0 feet.
- Flood History...This crest compares to a previous crest of
12.2 feet on 04/25/1993.
- http://www.weather.gov/safety/flood
Instruction:
Motorists should not attempt to drive around barricades or drive
cars through flooded areas.
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
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.
Additional information is available at www.weather.gov.
The next statement will be issued this morning at 630 AM CDT.
Area Description:
Jefferson, WI; Rock, WI
Forcast Office:
NWS Milwaukee/Sullivan WI