By Jeanne Sexton-Brown
The National Weather Service (NWS) has issued updated flood predictions for the Sheyenne and Maple Rivers. A news conference was held on Friday, March 25 by the NWS. Greg Gust, Warning Coordination Meterologist, Grand Forks, issued an update including data from the storm on Tuesday and Wednesday, March 22 and 23.
“Risk has increased throughout the mid to upper Sheyenne sub-basin and the Devils Lake basin, while several of the tributaries in the far northern basin have seen risks decrease slightly,” said Gust. “These changes are mostly due to the significant snow events on March 5-6 and on March 22-23, both of which mainly impacted the southern two-thirds of the basin. Otherwise, the northernmost third of the basin received only minimal new snowfall.”
According to Gust, this outlook still indicates that Devils Lake and Stump Lake will certainly rise (more than 90 percent probability) to a new record height in excess of a 1454.1 ft elevation, which is two feet above their previous record set last summer. These lakes could rise (30 percent probability) to a height in excess of a 1455.1 feet, or three feet above their previous record. Overall risk factors have been increased slightly for this update, largely due to above normal snowfall through March.
The Sheyenne River at Lisbon has a 98 percent chance of reaching minor flood stage of 15 ft; a 96 percent chance of reaching moderate flood stage of 17ft and a 72 percent chance of reaching major flood stage of 19 ft. There is a 93 percent probability for departure   from normal flood stage.
To put this into perspective the Sheyenne River in Lisbon crested on Monday, March 22, 2010 at 19.48 feet at 8 p.m. The highway 27 bridge had to be closed off to protect the public but was reopened on Tuesday afternoon. In 2009 the Sheyenne River crested for the second time on Friday, April 17 at 22.84 feet which broke the record by 3.5 ft. and resulted in the Highway 27 bridge being closed for a month.
The Maple River at Enderlin has a 98 percent chance of reaching minor flood stage of 9.5 ft; a 98 percent chance of reaching moderate flood stage at 12 ft; and a 56 percent chance of reaching major flood stage at 14 ft. There is an over 80 percent probability for departure from normal flood stage in Enderlin.
The NWS was predicting light snow or rain by Thursday, March 31 with a more significant warm-up and heavier precipitation events possible early in the first and second weeks of April.
“The later into April the snowmelt is delayed, the increased risk we have for heavier rains and a more rapid thaw cycle to commence,” said Gust. “Normal high temperatures climb rapidly from the mid 40s early in April to the mid 50s by mid month.”
The overall climate outlook for April calls for cooler and wetter conditions, while this active storm patter is expected to persist well into May.

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