FARGO — Favorable thaw conditions that so far have been "near perfect" are expected to continue through the weekend — but forecasters are watching a potential weather system that could bring precipitation next week.
The National Weather Service expects gradual melting to continue in the Red River Valley, according to a flood risk update issued Thursday, March 28.
"If conditions in the next several weeks continue to follow this pattern" — slow melting during the day with freezing temperatures overnight and dry weather — "Fargo-Moorhead can expect to see a flood crest ranging from 33.8 feet to 36.5 feet," Greg Gust, a weather service meteorologist, wrote in the update. Major flood stage in Fargo is 30 feet.
But Gust added that heavy precipitation, especially if it coincides with peak snow-melt river rises, could produce Red River levels in Fargo-Moorhead above 37.9 feet, the 50 percent probability in a recent flood outlook.
In that flood outlook, forecasters gave Fargo-Moorhead:
- a 25 percent chance of a 38.9 foot flood
- a 10 percent chance of a 40.3 foot flood
- And a 5 percent chance of a 41.4 foot flood, which would be a new record and would qualify as a 100-year flood.
The record Red River flood in Fargo-Moorhead crested at 40.84 feet on March 28, 2009, exactly 10 years ago.
Temperatures in the upper 40s across the far southern valley and into west-central Minnesota Wednesday prompted more rapid melting, causing flooding in the Wahpeton-Breckenridge area that affected many rural roads due to overland flooding.
The Red River in Wahpeton entered minor flood stage early Thursday and topped 20 feet by afternoon. Forecasters predict the river will crest Saturday at 13.6 feet, a moderate flood level.
"Across the remainder of the southern basin, river conditions remain mostly ice covered with some ponding of water on streams and rivers and in fields and ditches," the flood risk update said.
Snow cover across the southern basin is "rapidly decreasing" while the top layer of the soil is slowly warming and "may now be capable of soaking up some of this moisture."
"Roller coaster" temperatures should continue into the first half of next week, with chances of minor precipitation in the northern basin on Friday.
But computer models show a system "potentially targeting the Plains around midweek next week," the weather service said.
"However, it is much too far into the future for any specific locations or precipitation amounts," the update said, with the potential precipitation possibly coming in a mix of snow and rain.
"On the other hand, this system may miss our area completely with little to no precipitation."