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Published April 10, 2011, 04:48 PM

Flooding Update from NWS

The following is the entire flooding update for the Red River Basin provided by the National Weather Service

Precipitation and Wind Issues:

Light rain or mist affected much of the Red River Basin from Saturday evening into early Sunday morning. From mid-morning into midday Sunday a band of thunderstorms set up along a line from Aberdeen SD, through Fargo ND, to International Falls MN. This band produced scattered areas of from one-quarter to one half inch of rain along and east ward of that initial line. Isolated storms produced pea sized to penny sized hail from Wyndmere ND (Richland County) into Lake George MN (Hubbard County).

Widespread light rain also occurred to the west of the thunderstorm band, across most of the remainder of the Red River Basin. By 4 PM CDT, total rainfall amounts range from one-quarter to one-half inch north and west of a line from Jamestown ND, through Grand Forks ND, to Baudette MN – encompassing the northern Red River Basin and Devils Lake Basin.

South and east of this line, total rain fall amounts range from one-half to three-quarters of an inch, with isolated areas approaching one inch. Heaviest rainfall amounts have affected flood impacted portions of the Maple and Sheyenne River Basins in southeast ND (west southwest of Fargo) and the Buffalo River Basin in northwest MN (east of Moorhead).

Light rain is expected to continue from extreme eastern ND into northern MN through the late evening and overnight period, with additional new rainfall amounts from one tenth to one-quarter inch possible.

Winds are quite brisk across the area this afternoon, from the northwest at 20 mph gusting to 35 mph, producing waves of from 1 to 2 feet on large open-water or rural areas and in wider exposed portions of the Red River within Fargo-Moorhead. At these very high flood levels the Red River approaches three-quarters of a mile wide at points, and the river surface is much more exposed to winds than usual. Outside the city limits, Cass County ND and Clay County MN have numerous square miles of flood enshrouded farms and smaller communities which are being impacted by these winds and waves.

Mainly dry conditions are expected for the Red River Basin through the coming work week. A weak frontal system will pass through the area late Tuesday into Wednesday with a brief period of very light rain or sprinkles possible.

Along the Red River:

The Red River at Fargo-Moorhead reached a preliminary crest of 38.75 feet on Saturday evening, at 6:15 PM CDT. Since then, the Red River has dropped sufficiently in Fargo so that runoff from the current rainfall is not expected to push the river back to this crest level, and will act instead to prolong the period of high water.

Widespread breakout flooding is occurring north from Fargo and Moorhead. Portions of northeastern Cass County (ND) and northwestern Clay County (MN) are experiencing the highest flood levels ever seen. Record flows have recently been recorded by the USGS on the Sheyenne River near Harwood ND. These record flows are merging with the Red River north of Fargo and causing additional backwater levels along the Buffalo River (MN) north of Moorhead, near Georgetown. Harwood ND and Georgetown MN are experiencing worse breakout flooding than in 2009 or 1997 floods of record. Video shows the flow across I-29 north of Harwood, between mileposts 76 and 79.

Areas along the Red River northward from Fargo-Moorhead into Perley, Halstad, Grand Forks, Oslo, Drayton and Pembina are all seeing increased breakout flows and rural flooding as the river exceeds moderate and major flood stages. The Point Bridge and downtown Sorlie Bridge in Grand Forks have both closed due to high water, leaving the Thompson and Kennedy Bridges still opened. Numerous county and state roads are closed throughout the basin. Rainfall from this weekend along with record flows already coming into the Red River from the Sheyenne River will likely increase flows throughout these areas.

Along the Sheyenne River:

The upper Sheyenne River basin is seeing record flows above Cooperstown, with increasing flows being reported into Lake Ashtabula Reservoir above Valley City. The middle Sheyenne system is seeing steadily increasing flows from Valley City into Lisbon as local runoff is combining with releases from Baldhill Dam. Crests from Valley City into Lisbon are projected for early next week, with little or no ice problems expected.

Clausen Springs Dam, located on Spring Creek upstream of Kathyrn ND, is being watched closely by state and local officials as high flows are beginning to impact the recently repaired structure. A Flash Flood Watch has been posted for the Spring Creek area from the Dam, through Kathyrn, to the confluence with the Sheyenne River southeast of Kathyrn. This Watch is currently in effect through Tuesday.

Along the Sheyenne River downstream from Lisbon, the area from Kindred into Horace and West Fargo will see increasing breakout flow and overland flows through the coming week.

These increased flows should be moving into the Harwood area late in the week after the initial peak flows from the Maple and Rush Rivers have passed that area.

Along the Pembina River:

Remaining snowpack is spotty and largely confined to upland areas of far northeast North Dakota. This would include the upper reaches of the Pembina River and portions of the upper Devils Lake Basin. This remaining snowpack should be melting into the system early in the week.

Flows are increasing along the Pembina River at Walhalla and Neche. Higher flows are expected to come into the Pembina River system from Windygates, Manitoba, through the coming week. Peak flows along the Pembina River are expected to come into the community of Pembina near the time of peak levels on the Red River nearly two weeks from now.

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