Good afternoon everyone! We continue to track the winter storm across the region as it slowly works southeastward with time. A band of moderate to heavy snow lingers from Bismarck, ND southeastward towards Aberdeen and Watertown, SD. Light snows have also began to work into southwestern MN over the last few hours. This snow band has set up in an area of increased frontogenesis (development of a boundary that aids in lift), which is allowing for moderate snows to continue in these areas. Here’s a current look at the radar:
Winter Weather Advisories remain stretched from western ND southeastward through southern MN with a patch of Winter Storm Warnings just west of Bismarck, ND. Generally, the bulletins in ND last through the evening while advisories in southern MN remain in effect through early Saturday morning.
As we progress into the evening hours, the main band will shift southeastward with a greater focus over portions of northeastern SD into southern MN. Snows will generally lose coverage and intensity in ND as the boundary shits into the previously specified areas. Substantial rising motion can be noted in the Dendritic Growth Zone in the circled region, which results in bigger snowflakes that have an easier time accumulating. A change in wind direction with height also depicts that a boundary will be draped in this region, resulting in better lift and the development of snow.
Simulated radar through 6pm CST Saturday: The band of moderate to heavy snow shifts eastward through the evening with more of southern MN gradually working in these snows. Snow coverage and intensity in ND fades with time these evening, becoming lighter in nature while progressing southward out of the state by midnight tonight. Snow coverage increases in SD, but most of the state will generally see lighter snows with the better forcing located just east. However, northeastern SD continues the period of moderate to heavy snow through the evening. Progressing through the night, the focus of the snows will lift south and eastward and the snow coverage departing north to south. By 6am CST Saturday, the vast majority of the region will be drying out as the snows work out of southern MN. We can’t rule out lingering snow showers in the Blackhills and far southwestern SD through early Saturday afternoon. Definitely be wary of travel through this storm as roads will likely be hazardous!
Here’s an updated snowfall graphic through the course of the night: A swath of additional accumulations ranging from 2-4″ is expected from south-central ND into northeastern SD and southern MN. Localized pockets of 5-6″ of additional snow is possible within this region, especially near Bismarck where the heaviest snows are currently. As noted in this morning’s update there will be a tight gradient both on the north and south side of this system with areas like Sioux Falls and Minneapolis right on the edge of this gradient. Northern MN largely misses out on this storm system.
High pressure will work in and help to clear out skies overnight from north to south with some lingering snow showers early Saturday morning in southwestern SD and southeastern MN. This will allow temperatures in the areas that clear out and have substantial snowpack to really fall tonight. Areas with this snowpack in ND can easily drop into the single digits with some even falling below 0ºF by Saturday morning. Here’s a look at the low temperatures from the HRRR for Saturday morning:
With high pressure following in behind this storm system Saturday, skies will remain generally clear (darker shading) with only isolated to widely scattered pockets of clouds possible. Clouds will likely hang on just enough across southern SD and possibly far southern MN due to remaining influences from the system working out of the region Saturday morning. Temperatures will stay well below normal for this time of year, with highs in the teens likely in ND and northern MN.
If you have any questions do not hesitate to reach out! Have a great evening!