In its latest flood outlook released yesterday, the National Weather Service out of Grand Forks has indicated the risk of significant snowmelt flooding has again increased in parts of the U.S. Red River Basin.
Red River Basin Flood Risk is moderately high, with all main-stem points expected to see near to somewhat above normal spring runoff and flows.
There are currently near to above normal soil moisture in the south part of the basin, deeper than normal frost depths and moderate to high winter snowpack and Snow water equivalent to date.
Some other key details from the report:
Base Streamflow: Near normal for this time of year. USGS analyses indicate that the Red River and most of its ND and MN tributaries are thickly ice covered and/or flowing at 25% -75% of normal ranges. Somewhat higher in the far southern basin and somewhat lower near the CanAm border.
Frost Depth: Somewhat Deeper than normal. A quite cold mid-winter period has allowed for deep frost penetration in most areas. Frost depths range from 18 to 50 inches in most locations, with deepest frost penetration across the northern reaches, and in upland areas of northwest MN, where early snowpack was lighter.
Winter Snowpack/SWE: Somewhat Above normal. Since Dec 1st, snowfall runs from 90-140 percent of normal, SWE ranges from 2.0 to 5.0 inches [70th to 90th percentiles]. Well distributed across the sub-basins, but quite splotchy due to relocation of snow during frequent blowing snow and blizzard episodes.
There is a high risk, greater than 65 percent chance, of major flooding at Pembina, North Dakota on the Red River.
Meanwhile, along the Pembina River, there is little chance of flooding based on current projections, with only a 25% chance of reaching moderate flood stage at Neche.
Climate outlooks currently indicate a volatile next couple of weeks, cold-to mild-to cold, with a trend toward near normal temperatures and precipitation, mid-March into April, which the report indicated will help to keep overall risk in check on the U.S. side of the border.
The take away from the report is the risk for significant snowmelt flooding is moderately high, running somewhat above long-term historical averages, across the U.S. portion of the Red River.
The report is based on conditions through February 22nd. The next flood outlook will be released March 10th.