Substantial flooding likely in Devils Lake Basin and Red River Valley.
Gregory Gust, Warning Coordination Meteorologist and Mike Lukes, Service Hydrologist National Weather Service out of Grand Forks have released the outlook for flooding for this region for the coming spring of 2013 and it doesn’t look good.
This outlook is based on conditions as of March 21, 2013. Official textual and graphical outlook products are available at weather.gov/fgf and at devilslake.noaa.gov .
Their prediction: “A substantial flood is likely, similar to recent 2010/2011 scale floods.”
Way above normal new snowfall and snow water content has been received since the February outlook was released, with greatest increases again in the far south and far north portions of the basin. Water content of six inches or more is common south/east of Wahpeton (south basin) and along the Canadian-American border.
There is now a major flood risk along most of the mainstem Red River, with significant breakout/overland flows to be expected. Portions of the I-29 corridor could be impacted.
There is now a minor to moderate, and some major flood risk along most tributary streams and rivers in eastern ND and Northwest Minn., especially nearest the Red River.
Devils Lake should see more appreciable inflows and a 2.0 to 2.5 foot overall rise, with overland flooding increasing across northern portions of the basin.
Cool and snowy/wet conditions should delay the initial runoff into early April… then the risk for a rapid warm-up and convective rain events will increase – a potentially volatile mix.
Key points for the Red River Basin, from south to north:
In the far South Basin: 10 percent risk of Flood of Record!.
- Wahpeton-Breckenridge on the Red has >95 percent risk of Major flooding - 50 percent risk of 17.2 ft.
- Fargo-Moorhead on the Red has >95 percent risk of Major flooding - 50 percent risk of 38.1 ft.
- Abercrombie on the ND Wild Rice has >95 percent risk if Major flooding - 50 percent risk of 24.7 ft.
- Sheyenne River, Kindred and Blo had Moderate to Major risk. Harwood on edge of FOR.
Expect significant overland flooding to develop, especially in Wilkin and southern Clay. Some breakout flow from the Bois de Sioux into the Wild Rice south of Wahpeton. Sheyenne should be somewhat less troublesome than in 2011. Expect I-29 trouble spots.
In the mid to upper Sheyenne Basin: Low risk at and above Lisbon. Expect some breakout flows and overland flooding in far northwest headwaters (western Eddy Co.). Else, at this time Baldhill Dam is expected to be able to regulate slower/lesser overall flow/volume.
Page 2 of 3 - In the central Red River Basin: Somewhat increased risk of Moderate to Major flooding.
- Major flood levels (low edge) expected at Halstad, Grand Forks, and Oslo on the Red River.
- Mainly Moderate flood flows expected on central RRV tributaries – but all up significantly!
- Grafton on the Park River now has a 48 percent risk of Major flooding – 50 percent risk of 14.5 ft.
The upper Red Lake River has significantly more snow-water than earlier, but headwaters areas should absorb this to a degree. Otherwise the rest of the area is a bit above normal snow-water. Still should expect some breakout flows and overland flooding near streams and ditches.
In the Minnesota Lakes: Expect significant localized runoff. Significant snowpack and snow-water should produce local runoff into area lakes and sloughs, with areas of overland and out of bank flows. Area roads and bridges are likely to see some impact periods.
In the Roseau River Basin: Expect significant localized runoff.
Significant snowpack and snow-water should produce local runoff and some ponding to overland flows. Most area soils are more porous and will allow for increased infiltration rates. Roseau at 50 percent risk of 16.4 ft. (Moderate). On edge of Major flooding if heavy rain events materialize!
In the Pembina Basin and northern Red River Basin: Big snowpack and runoff concerns!
- Pembina on the Red River now has a >95 percent risk of Major flooding - 50 percent risk of 52.0 ft.
- Neche on the Pembina River now has a >95 percent risk of Major flooding - 50 percent risk of 21.4 ft.
- Hallock on the Two Rivers River now has a 88 percent risk of Moderate flooding.
- Drayton and Pembina risk levels along the Red River here are looking similar to 2011 levels.
Significant snowpack from the headwaters of the Pembina River (in Manitoba) through northern Pembina County should create significant riverine flows and contribute to a high potential for breakout flows across far north central into northeast Pembina County.
Key points for the Devils Lake Basin: This outlook now indicates that Devils Lake and Stump Lake could rise (50 percent probability) around 2 to 2.5 feet, due to a somewhat above normal topsoil wetness and a much above normal snowpack. [Creel Bay gauge at 1451.58 on 3/21/13]
-- Last year, these lakes dropped nearly 3 feet from their 2011 record height, freeing up some 30,000 acres of farmland… much of which could be lost again this year.
-- Such high inflows will likely mean some carryover rises into next year, as summertime evaporation and mechanical pumping will likely not be able to take all this off in this year alone.
Page 3 of 3 - Next steps:
Community/County scale planning and coordination continues, while networks continue to monitor new precipitation and prepare for onset of snowmelt runoff. Once runoff commences the river forecast effort shifts from probabilities to deterministic 7-10 day river forecasts.
Expect weekly thaw progress and runoff expectation (descriptive Hydrologic Outlooks - ESFFGF) reports each Friday, or more often if needed.