As for the immediate term, the biggest worry is the accumulation of snow in the southwest and south-central North Dakota, which will continue tonight through Christmas Day.
According to the National Weather Service, extremely low wind chills are also forecast over northern North Dakota tonight and into Christmas morning.
Warm air from the north has flowed across the state earlier today, causing temperatures to stay mostly stable, if not falling, since early this morning.
The weather has turned blustery, with a brisk northwest wind pushing snow from the Devils Lake Basin into the northern James River Valley. Because of a surface ridge stretching south and east of high pressure over Alberta, winds will gradually weaken during the evening.
The ridge will eventually reach North Dakota. Temperatures might plunge over northern North Dakota tonight due to the lack of cloud cover, which will be less broad than in the southern part of the state.
A Wind Chill Advisory has been issued for locations north of Highway 2 and along its route, which will be effective from this evening until Christmas morning. Wind chills might reach 30 below zero, prompting the issuing of the advisory.
During the nighttime hours of this evening, a shortwave trough will be propelled from the base of an upper low off the Pacific Northwest coast and will swiftly reach the Northern Plains by noon Christmas.
Downstream forcing from the isentropic ascent, mid-level frontogenesis, and low-level warm air advection will begin over southwest North Dakota late tonight.
Still, precipitation onset may be delayed until firmer aloft support, including strong mid-level DCVA/PVA and Q-vector convergence, arrives early in the morning on Christmas Day.
Even at this shorter period, confidence in the location of the maximum snow accumulations is low to moderate at best, as is the case with the majority of banding occasions.
The projected track of the synoptic-scale features is also subject to some uncertainty; however, 12Z guidance has shown considerable consolidation between Interstate 94 and the South Dakota border, which corresponds to the consistency of the ECMWF ensemble from run to run.
From late tonight until Christmas Day, a Winter Weather Advisory has been issued for locations along and south of Interstate 94 in the state of Minnesota.
If mesoscale banding occurs, the maximum snow accumulation predicted by the HREF predicts a localized high-end possibility of up to 8 inches in snow accumulation.
It will be quite cold on Christmas Day, with high temperatures ranging from about zero around the Canadian border to near 20 in far southwest North Dakota.
It will be windy, with gusts up to 10 mph from the east to the northeast. A persistent agitated/cyclonic flow aloft might bring light snow to the remainder of western and central North Dakota throughout the day.
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