April 21, 2011
Forecasters with NOAA’s National Weather Service have begun alerting local communities, emergency management agencies and water managers of the strong possibility heavy rain that will cause significant flooding early next week to main rivers and tributaries in parts of the Mississippi, Missouri and Ohio valleys.
Rainfall forecasts for many locations from the southern Great Lakes across the Midwest to southern Oklahoma and northern Texas are calling for 3-7 inches and possibly more. Much of that rain will fall on saturated soil that will absorb very little, if any, of the new water. Resultant runoff water will cause rapid rises and flash flooding as well as significant river and overland flooding in many areas.
“Forecasters have determined there will be a very significant amount of precipitation falling in areas that don’t need any more rain at the moment,” said National Weather Service Central Region Director Lynn P. Maximuk. “River valley residents are accustomed to springtime floods, but this weekend those drainages will see torrential rain that will push flood levels well above normal stages. Our offices have already started advising local communities about the situation through NOAA Weather Radio broadcasts and agency web sites.
“We encourage all residents of potential flood areas to pay close attention to current conditions and local forecasts so they are prepared to take any protective actions needed.”
Forecasters at NOAA’s Hydrometeorological Prediction Center said rain in the Plains, Midwest and Ohio Valley will last through the weekend, dropping from about three inches of rain in southwestern Pennsylvania to more than six inches in northwest Oklahoma.
National Weather Service weather and river forecast centers, along with supporting regional offices and headquarters departments have conducted multi-agency briefings using teleconferences and webinars to advise local officials of rainfall and flood probabilities. NOAA is working closely with local, state and federal water and disaster management communities to prepare communities for flooding.