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for South Central and Southeast Wisconsin
Flash Flood Threat
Hazard Map Threat Levels Safety & Impact
Flooding Safety Rules

Learn your vulnerability to flooding by determining the elevation of your property. Evaluate your insurance coverage; as construction grows around areas, floodplains change. If you are in a flood area, consider what mitigation measure you can do in advance.

In highly flood-prone areas, keep materials on hand like sandbags, plywood, plastic sheeting, plastic garbage bags, lumber, shovels, work boots and gloves. Call your county emergency management agency to learn how to construct proper protective measures around your home.

Be aware of streams, drainage channels and areas known to flood, so you or your evacuation routes are not cut off.

Monitor NOAA Weather Radio.

Avoid driving into water of unknown depth. Moving water can quickly sweep your vehicle away.

Restrict children from playing in flooded areas.

Test drinking water for potability; wells should be pumped out and the water tested before drinking.

Do not use fresh food that has come in contact with floodwaters. Wash canned goods that come in contact with floodwaters with soap and hot water.
Stay away from downed power lines.
Watches, Warnings & Advisories
Flood Watch
A flood watch means that flooding is possible within (or near) the desgnated watch area - be alert.
Flood Warning
Flooding has been reported already, or is imminent - take necessary precautions at once.
Urban and Small Stream Flood Advisory
Flooding of small streams, streets, and low-lying areas, such as underpasses, storms drains, is occurring.
Flood Statement
Follow-up information regarding a flood event.
Flood Statistics 
Statistics to remember if you are ever faced with the decision of crossing a flooded roadway
As little as one foot of water can move most cars off the road.
Just six inches of fast-moving flood water can sweep a person off his or her feet. 
Most flood-related deaths occur at night and are vehicular.
Urban and small stream flash floods often occur in less than one hour.
Tropical cyclones pose significant risk well inland due to fresh water flooding.
EXCESSIVE RAINFALL AND FLOODING.
Never Drive Across a Flooded Road!

Whether it is a severe thunderstorm, or a large and intense low pressure system, heavy rainfall in Wisconsin causes flooding problems.

When a large amount of rain falls over a short period of time, ditches, rivers and lakes become filled with water and overflow into low-lying or poorly drained areas. In addition to the high frequency of excessive rainfall events, the impacts of flooding in Wisconsin may increase as the state's population and urban development grows.

Flood Statistics

Statistics clearly point out the high risk of driving in and around flooded roads and low spots. Usually, individuals between the ages of 30-39 years old attempt to drive through flooded roads only to be wisked away by rushing waters. The rule is simple: if you cannot see the road or its line markings, do not drive through the water.

Effect of Moving Water on Vehicles

Moving water exerts a pressure on an object such as a car or person. As water depth increases or a greater area is exposed to moving water, a greater force will be exerted. Also, as a surface becomes slippery, friction is reduced. Water, sand, or mud tends to replace the frictional forces that hold a car in place. 

Consideration of Sport Utility Vehicles (SUVs)

Even though the weight of Sport Utility Vehicles (SUVs) may appear to offer a greater protection in crossing flooded roads, their size and larger tires can make them more buoyant and more prone to being swept away. Bottom Line: It is just as dangerous to drive an SUV through flooded waters as a regular vehicle. 

Pooling of Water

Flat terrain makes it much more complicated to drain accumulated water. When rivers rise, water tends to spread out far from riverbanks.

Pooling of water poses a significant risk, not as much from swift moving water, but more from one's inability to judge water depth. Water only inches deep can be next to water that is several feet deep.

  • National Weather Service
  • Milwaukee/Sullivan, WI Weather Forecast Office
  • N3533 Hardscrabble Road
  • Dousman, WI 53118
  • 262-965-2074
  • Page Author: MKX Webmaster
  • Web Master's E-mail: w-mkx.webmaster@noaa.gov
  • Page last modified: 2-Nov-2005 10:23 PM UTC
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