AccuWeather.com

By Alex Sosnowski, Expert Senior Meteorologist

Mar 17, 2010; 9:30 AM ET

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While rivers are receding in the Northeast, many rivers over the central and northern Plains are rising and in some cases will contribute to record flooding in the coming days and weeks.

New England

Record flooding has occurred along some of the short-run rivers in southeastern New England as a result of heavy rainfall from this past weekend's storm.

While rivers are receding now some will remain above flood stage through the end of the week including the Taunton, Nashua, Sudbury, Assabet, Ipswich, Charles and Pawtuxet.

Concerns remain through much of the spring due to the amount of snow still on the ground in northern areas and saturated ground elsewhere. Additional storms this spring have the potential to drop heavy, wet snow or rain. Late-season snowstorms have an elevated risk of rapid meltdown.

Mid-Atlantic

Flooding in the Virginias, New Jersey and other mid-Atlantic states has peaked with most rivers beginning to recede. However, one river in particular, the Passaic, will remain above flood stage into the weekend.

Like New England, concerns remain through the first part of the spring due to the saturated state of the ground. There is still a significant amount of snow on some of the mountains. There is still the risk of late-season snowstorms for the next several weeks that could put down new snow that may rapidly melt.

Ohio Valley

Minor flooding is expected to continue over the next week or so along portions of the Ohio River due to run-off from melted snow and recent rainfall. Rivers that drain into the Ohio, including the Wabash and White have crested or will crest over the next couple of days after many of them cause minor to moderate flooding.

Concerns remain through the first part of the spring due to saturated ground and the potential for additional storms bringing more rain and perhaps wet snow that could rapidly melt.

It is too early to say with confidence on how this will affect the planting season (corn). The flooding is occurring a bit earlier than average, and the ground may have a chance to dry out before the planting process begins.

Northern Plains

Many river levels over the northern Plains are near or above flood stage and are expected to remain in this state for months.

In addition to the threat on individual communities, some unprotected agricultural areas will be under water for weeks. However, like the Midwest, the flooding is occurring much earlier than average, and there may be time for the ground to dry out before the planting season is greatly impacted.

Moderate to record flooding is occurring and is expected to continue in some areas for the next several weeks to a month or more, depending on the size of the river in a particular area.

There has never been back-to-back years of major to record flooding along the Red River of the north in its 110-year history according to National Oceanic and Atmospheric Administration hydrologists.

According to Jack Hayes, director of the National Weather Service, the snowpack over the northern Plains prior to the start of the thaw ranked in the top 10 since World War II. A lack of complete thaws during the winter have caused the snow over the northern Plains to retain most of its moisture.

Portions of the James and Red rivers will achieve record levels. At Fargo, the Red River may come within a couple of feet of the record mark set just last year.

The Little Sioux River has set record levels in northwest Iowa.

While the threat of ice jams causing rapid rises in Iowa is passing, it remains as a valid concern in areas farther north, where there is still extensive snow on the ground and river ice is just beginning to break.

Ice jams can cause rivers to rise several feet in several minutes putting unsuspecting residents at risk.

Des Moines, Iowa, lies at the confluence of the Des Moines and Raccoon rivers. While officials do not expect another repeat of 2008, they are preparing for that possibility by upgrading existing levees and the placement of temporary flood retention systems. Moderate flooding is expected in the Des Moines area.

Other communities and states in the region are preparing for flooding and are working with FEMA.

Moderate to major flooding is occurring over much of Iowa. Most rivers are expected to crest this weekend in the state as a significant part of the snowpack in this particular basin has already melted.

The exact levels the rivers and streams achieve in the region are highly dependent on the rate of existing snowmelt and future storms.

AccuWeather.com meteorologists expect the release of more water over the Dakotas and southwestern Minnesota during the next few days as warm air flows over the snowcover.

Beginning this weekend and through the next several weeks, the upcoming weather pattern supports invasions of cold air, which may slow the rate of snowmelt at times, while additional storms threaten to bring rain and even more snow that could rapidly melt at some point.

As a result, the prediction of river levels in the area and downstream locations in the weeks ahead are very complex and uncertain.

Southeast

Winter rainfall (and snowfall) has been well above average this past season in the Southeast states. Moderate storms in the past couple of weeks have demonstrated how easily stream and river flooding can occur, given the saturated state of the ground.

Similar to the Northeast, much of the Southeast remains at an above-average risk of flooding this spring. The storm passing through now is working to keep the ground wet.

Even though the El Nino is in the weakening stages, there is a likelihood of several additional potent rainstorms swinging through the region, initiating new or elevating existing stream and river flooding problems.

The lower Mississippi River is just in the beginning stages of its spring rise and is still weeks, if not a month or more, away from cresting due to the spring rain and thaw up north.

Since the exact amount of upcoming rainfall in the South as well as the precipitation and behavior of the thaw in the north cannot be determined, the magnitude of downstream flooding is questionable.

Moderate flooding of the Mississippi River is expected in much of the states of Missouri and Illinois during the next couple of weeks.

A significant part of the flow from the Mississippi River in the South is gained from the Ohio River.

At this point, there appears to be a significant chance of minor to moderate flooding along portions of the lower Mississippi River in the months ahead.

Throughout the Eastern Two-Thirds of the Nation

Regardless of the flooding situation in your particular location, a saturated ground in most areas has resulted in an above-average risk of flooding this spring.

Even a moderate amount of rain in a short period of time has the potential to cause stream and river flooding on the local level.

The sun is strengthening and the days are getting longer, increasing evaporation rates. Hopefully, as the spring progresses, more areas will back out of the flooding potential that now exists.

Related to the Story

How to Clean-up after a Flood

Mitigating Damage from Wind, Rain and Flood