A spring/winter storm looks to impact the region Tuesday and have a long duration with impacts felt into Wednesday and Thursday. There remains uncertainty with the track of this storm system, but there are protentional for rain, strong thunderstorms, heavy wet snow, and strong winds.
Currently, weather models are pushing more of the precipitation northward than displayed a few days ago. This also pushes more the of the significant snow up into the northern areas as well where Winter Storm Watches are already in place.
Breaking it down starting with Tuesday morning, rain and thunderstorms are expected in the east. The west will see chances of rain, mixing, or changing over to snow. Below are the three weather models showing the model's prediction of precipitation at 7:00am CDT, Tuesday morning.
By Tuesday afternoon, much of the precipitation looks to be across the northern and western regions of the state with a mixture of rain or snow in the northwest corner of South Dakota.
Once Tuesday evening, models are showing wintry weather continuing for the northwest with rain mixing or changing over to snow in the west. Rain and thunderstorms are possible across central and eastern regions.
Some of these thunderstorms on Tuesday could become strong to severe. The best risk of severe weather will be in the far southeast corner of the state near Elk Point and Sioux City.
Pushing ahead into Wednesday morning, weather models are showing snow chances for the northern ends of northwest and north-central, South Dakota with chances of rain for the east. The Euro and American models keep much of the precipitation near the border of North Dakota and South Dakota with the GEM model pushing some of the precipitation southward.
By Wednesday evening, most of the precipitation falling should be in the form of snow with the best chances of snow across the north with scattered chances elsewhere.
Snowfall amounts at this time, look to be the heaviest across the northwest where over a foot of snow is possible. Amounts quickly decrease the more south and east you go.
Snowfall Forecast (Sunday 7pm - Wednesday 7pm CDT):
Aberdeen: 1-3" Bison: 12-14"
Eagle Butte: 6-9"
Pine Ridge: 0-1"
Rapid City: 3-6"
Sioux Falls: 0"