Risk of major spring flooding along Red River creeps up as snow keeps coming

There is a high risk of major flooding along the Red River at the Manitoba border this spring, according to a new outlook from the U.S. National Weather Service.

While minor to moderate flooding — with occasional low-end major flooding — is expected across most of the Red River basin in the northern U.S., it increases closer to the international border.

A flood is deemed to be major at the border town of Pembina, N.D., when the river level hits 49 feet. There is a 65 per cent chance of that this spring and a 50 per cent chance of it hitting 50.3 feet.

The record level was reached during the 1997 flood, when it measured 54.94 feet.

Frost is deeper than normal due to a fairly extended period of cold conditions throughout January and early February. That has allowed frost to push down 12-40 inches (30 cm to more than a metre) in most of North Dakota, with the deeper amounts farther north, Amanda Lee, hydrologist for the U.S. National Weather Service, said during a news conference on Thursday.

Similarly, the snowpack has continued to grow but there unevenness is wide spread due to several blowing snow and blizzard events over the course of the winter, she said.

That situation is being exacerbated by yet another storm. A blizzard warning has been issued through parts of North Dakota and Minnesota with a system expected to pass through the Red River corridor between 9 p.m. Thursday and 9 a.m. Friday.

There is some relief in sight, though. The climate outlooks, while colder and snowier now, is trending toward near-normal conditions by early spring, the weather service report stated.

This winter marks a significant turnaround from 2021, which was the record driest year on record, but it's not nearly as wet as the flood years of 2019 to early 2020.

In those years, the river level at Pembina peaked at 49.38 feet and 50.57 feet, respectively.

The lingering drought conditions from 2021 mean there is room in the surface soil levels to absorb a good amount of snow melt if the thaw is gentle and drawn out, the weather service report said.

The U.S. spring flood outlook will be updated every couple of weeks. The Manitoba government has not yet released a flood forecast.

Eight more centimetres of snow on Thursday brought Winnipeg's seasonal total to 128.2 cm, according to Rob Paola, a retired Environment Canada meteorologist who runs the popular Twitter account @robsobs.

The average snowfall for an entire winter is 127.6 cm, and there are still 2½ more months of snow remaining.

Winnipeg received 43.2 cm of snow in January 2022, while it recorded only 11.4 in January 2021.

"We are double the snowfall we had at this point last year," Paola tweeted.

Highway 12, from Steinbach to the U.S. border, was closed just after noon Thursday due to poor winter driving conditions.

The Lord Selkirk School Division, which stretches from St. Andrews up to the lakeshore communities of Grand Marais and Victoria Beach, posted on its website that worsening road and weather conditions have forced it to cancel buses.

Parents were being asked to pick up their children from school as soon as possible, though classes were set to continue for the day.