Property owners should consider clearing snow away from their home to reduce the chance of indoor flooding, said the National Weather Service (NWS) Duluth on Thursday.
“Ideally, clearing about three to four feet away from your foundation will reduce the chance that you have flooding in your basement or on your first floor,” said Joe Moore from NWS.
Moore recommended that property owners ensure their sump pump is working properly and to consider getting a back up. “If we do have a heavy rainfall event in the month of April that could really overwhelm sump pump systems,” he said.
Property owners should also move valuables and hazardous materials away from basements and store them upstairs in other higher locations, and remember to clear snow away from storm drains, fire hydrants, gutters, downspouts, and over entrances.
There are multiple variables that affect snow melt rate. Faster melt rate will depend on nighttime low temperatures that are above freezing, faster wind speeds, higher dew points, sunshine, precipitation on snow, and the frost depth as more frozen grounds will result in more direct runoff into rivers and lakes.
So far, measurements have shown that snow amounts and snow water equivalent (SWE) continues to increase across the area, increasing the risk of spring flooding.
The risk for moderate or major flooding has increased in the Mississippi River Aiken and Fort Ripley.
There is also a risk increase for minor flooding on the Bad River and the St. Louis River.
Without a big snow melt at the moment, flooding forecasters said it’s difficult to know what will happen.
“But that’s something that we’ll be focusing on as we hopefully get into melt season here pretty soon,” said Ketzel Levens from NWS Duluth.
One of the biggest differences compared to last year is the height of this year’s snowpack, said Moore, who added that most places were melted already around March 2022.
“Not only has it been a top 10 winter for snowfall, and the amount of water in that snow, but also we still have it. It should be melting by this point but it hasn’t. The longer we push this off the bigger potential that it all melts at once and causes some pretty devastating flooding,” Moore said.
Wet rain events and wintry events have removed any signs of a drought, said Levens.
“Last year, you were getting pretty dry by the end of fall, we’ve pretty much removed any signs of drought, and our soil is moistening because of that. So we’re not dry anymore, and we do have moisture returning into the soil,” she said.
The two-week outlook determined there will be below normal temperatures and slightly above normal precipitation levels, having a neutral impact on spring flooding as cooler temperatures are better to keep the snow melt slower.
Compared to historical records, SWE numbers are higher by around 10 to 20 per cent, said Levens, adding that the Rainy River is an exception with only slightly above normal SWE numbers in some areas.
“All of our basins are much above normal snow water equivalent, the one exception being the Rainy River, which is only slightly above normal in some areas,” she said.
Levens warned that the same flooding problems that occurred last year will likely occur this spring.
“Something we’d really like everybody to take home is that if you have experienced spring snowmelt flooding problems in the past, whether it is that you live on a major river and have experienced it, or you just had back roads impacted or a basement flood, you will likely experience those problems again this spring,” she said.
“Exactly how that snow melts off is going to be very dependent on weather conditions, but in the long term, it’s going to be really hard to get around just how much water we have in the snow right now and still be able to go without flooding. So we are expecting that to have at least some minor impacts.”
Further flooding forecasts will be provided in the upcoming weeks. The next scheduled briefing will be by April 7, 2023.
For more information, visit https://www.weather.gov/dlh/spring-flood-outlook.
