REGIONAL- It’s likely that no one in the North Country was caught off guard by last week’s spring flood forecast issued by the National Weather Service office in Duluth, which concluded that the risk is just about as minimal as it can be after a record warm winter with little precipitation.
“Snowpack and the water contained within it are at historically low levels,” said meteorologist Ketzel Levens. “The chance for spring flooding is much lower than normal. Precipitation through early spring will be one of the most important flood risk factors. There is currently no strong signal for above or below normal precipitation in the long-range outlooks.”
“Much lower than normal” translates to less than a five percent chance of minor flooding in the Rainy River basin, and for the majority of the Upper Mississippi basin and West Lake Superior basin as well. Only Atikin, Ft. Ripley, and the Tyler Forks River near Mellen have elevated risk of minor flooding, calculated to be around 17 percent.
Nearly all of the winter factors that contribute to spring flooding – higher river levels, high soil moisture, winter precipitation, snowpack liquid equivalent, and rate of snowmelt – are all normal to below normal in the NWS assessment. Only frost depth is currently rated as having higher potential impact.
It takes only a glance at the mostly brown landscape in the North Country to know that current snow depth is at record low levels for this time of year. Snow depth is up to two-and-a-half feet below normal, with many areas having the lowest snow depth on record for late February. The snow water equivalent is in the range of under ten percent of values in the historical record dating back to 1948. Fifty percent would be near normal.
Snow conditions are an indicator that the region is suffering conditions from abnormally dry to severe drought, which is keeping stream flows at or below normal levels.
Soil frost conditions could be a complicating factor if the area receives early heavy rains, something not predicted by the NWS long-range forecast models. The frost measurement at the NWS office in Duluth last week was 21 inches, meaning the ground is deeply frozen and would not allow sufficient absorption of heavy rain.
March temperatures have a 50-60 percent chance of being above normal, making it more likely that any falling precipitation will come as rain, not snow. There are equal chances in the forecast models of precipitation being above, below, or at normal. The extended seasonal forecast through May is for more of the same, having a neutral impact on spring flooding.
The NWS will issue a final spring flood outlook on March 15.
In a related item, the International Rainy-Lake of the Woods Watershed Board Water Levels Committee met Tuesday in International Falls to take public comment about the rule curve to be implemented this year to control lake levels in the Rainy basin. The committee was scheduled to announce its decision on Friday. No information about what was reported or said at the meeting was available as of the Timberjay’s press deadline.