730 FXUS63 KBIS 301757 AFDBIS Area Forecast Discussion National Weather Service Bismarck ND 1157 AM CST Tue Dec 30 2025 .KEY MESSAGES... - Warmer today, then a large spread in temperatures from northeast (colder) to southwest (warmer) mid to late week. - Medium to high chances for snow mainly across central and eastern North Dakota Tuesday night into Wednesday. && .UPDATE... Issued at 1157 AM CST Tue Dec 30 2025 Precip has ended across central ND. Could be a sprinkle/shower that grazes the Turtle Mountains area later this afternoon, but attention now goes to the next clipper system and backdoor front that pushes west through the area tonight. Attim it looks like snow will be limited to the Turtle Mountains and northern JRV. Will take a closer look though. Will also need to check for possible low stratus/fog along the backdoor cold front. One thing that does stick out, except for the far southwest, it looks like the Highs on New Year's Eve will occur in the morning with falling temperatures through most of the day. Then possibly rising temperatures in the west after midnight. Updated text products will be transmitted shortly. UPDATE Issued at 933 AM CST Tue Dec 30 2025 Area of isolated to scattered showers is quickly pushing southeast, out of the forecast area this morning. Other than a stray sprinkle/flurry, we should remain dry until the next clipper system drops southeast from Canada this evening. Mild today with highs mainly in the 30s. UPDATE Issued at 600 AM CST Tue Dec 30 2025 Areas of weak and pockets of moderate reflectivity linger over north central North Dakota into the northern James River Valley. These radar signatures have diminished rapidly over the past two hours conditions above the 850mb layer have dried out significantly. That being said, another push of moisture is moving in across the north central at this time. Evidence for precipitation reaching the ground is mainly restricted to this area, and much of this has fallen as a wintry mix of freezing rain and snow due to the erosion of the 950 to 850 mb warm nose aloft. QPF reports from automated weather stations have broadly been from a trace to 0.01" along a line from Minot down through Jamestown. In the Turtle Mountains Area, slightly higher amounts up to 0.05" were observed. Here, analysis reveals a short lived band of enhanced precpitation developed where moderate FG forcing and Q-G convergence overlapped. All remaining precpitation is expected to move east out of the forecast area by the mid morning. With this update, have made some slight adjustments to PoPs to account for a slightly slower erosion of its western flank, and have blended in the latest satellite and model trends into the sky cover. Otherwise, the forecast remains on track at this time. && .DISCUSSION... Issued at 345 AM CST Tue Dec 30 2025 Northwesterly flow is found over the northern Plains this morning. A shortwave and associate surface low system has developed over the southern Canadian Prairies, and is expected to cut across northeastern North Dakota on its way to the Great Lakes through the day today. A warm front and trailing surface trough associated with this low pressure system is currently passing from west to east this morning. With the ongoing WAA, scattered precpitation has developed across northwestern and central North Dakota. A somewhat shallow 950 to 850 mb nose is evident on BUFKIT model soundings across this area as the WAA continues, which will allow for periods of light freezing rain mixed with snow through the mid morning, mainly behind the aforementioned warm front. With drier air wrapping around the low at the 850mb layer, and the relatively quick moving nature of this system, the period during which precpitation falls is fairly brief, and thus overall accumulations are expected to remain light. That being said, there is an axis of low to medium chances for a glaze of ice from the Turtle Mountains area to Fargo through the mid morning. The best potential for such remains over the Turtle Mountain area, as the residence time of precpitation is highest here. We have opted to issue an SPS across much of northwestern and portions of central North Dakota due to the very light nature of these accumulations. Otherwise, low temperatures are expected to range from the mid single digits across the James River Valley north through the Turtle Mountains area, up to the upper teens in the southwest. Mainly dry conditions are then expected through this afternoon, though CAMs continue to hint at limited banded precpitation potential across eastern North Dakota at this time. Depending on where this actually develops, portions of the James River Valley could see a brief period of light rain this afternoon, though confidence in this is very low. Otherwise, for today, breezy northwest winds sustained up to 25 MPH and gusting as high as 35 MPH are expected this afternoon as cold front and thus moderate CAA digs in from the north this afternoon and evening. A 40kt 850mb jet will be lingering across the east at this time, though the timing is such that fully mixing these winds down seems unlikely. High temperatures this afternoon are forecast around freezing in the Turtle Mountains area, up to the upper 30s and lower 40s in the southwest. With the cold front passing through the region this afternoon through tonight, a fairly stark NW-SW orientated baroclinic zone is expected to set up somewhere across the state. A clipper system is then progged to develop along this baroclinic, promoting medium to high chances (40 to 80 percent) for precpitation early tonight through Wednesday morning. While much of this is anticipated to fall as accumulating snow, brief periods of a wintry mix of light freezing rain and snow is possible along the southwestern edge of the baroclinic zone. No ice accumulation is currently anticipated. Overall snow accumulations remain in line with the past few forecast cycles, with the axis of highest amounts found in the Turtle Mountains area down to Fargo. Broadly speaking, less than an inch expected in the northwest and south central, and an inch or two north central into the northern James River Valley. Two things to keep in mind with these amounts are 1) The axis of highest accumulation is highly dependent on the location of the baroclinic zone which, while confidence is increasing in a slightly more eastern placement, can still chance and 2) there has been a pervasive banded snow signal for the past few days as moderate to high FG forcing and decent lapse rates are expected. Locally higher amounts of snow should be anticipated where ever these bands set up, and there remains a good amount of disagreement between individual ensemble and HREF members as to where this would be. The majority of members (approximately 67%) favor this to be along the aforementioned axis of highest snowfall from the Turtle Mountains down through Fargo, though a minority cluster (approximately 33%) also exists and instead favors this banded snow setting up from a line from Minot down through Jamestown. Looking ahead Wednesday through the end of the workweek, cyclonic flow is expected to develop over the forecast area as a Hudson Bay Low retrogrades into place. A strong temperatures gradient lingers through Wednesday the backside of the cold front, with highs from around zero in the Turtle Mountains are up to the mid 30s in the southwest and lows from 10 below north central to the lower 20s above southwest overnight. Longer term models continue to be somewhat discordant during this period as they struggle to resolve its interaction with the remnants of the clipper. The majority of ensemble members (approximately 75%) continue to favor near to slightly above normal temperatures through the weekend as the two lows merge and deepens over the bay. Notably, a minority cluster (approximately 25% membership) instead favors much cooler temperatures through this period as these lows orbit and displace each other through the weekend. Otherwise, there is no strong signal for precpitation through Saturday though the odd shortwave transient shortwave traversing the cyclonic flow could allow for low to medium chances for light precpitation basically any day. By Sunday into early next week, the ensemble becomes even more discordant as the the displacement of the Hudson Bay Low could allow for the breakdown of the cyclonic flow pattern. When and how the synoptic flow evolves during this timeframe remains uncertain, though a pattern shift some time during this period seems like a decent bet. && .AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/... Issued at 1157 AM CST Tue Dec 30 2025 Expect mainly VFR conditions to begin the 18Z TAF period, although there are some patches of MVFR clouds that may briefly pass over the southern TAF sites early in the period, before lifting to VFR category. Northwest Surface flow today generally 10 to 20 kts, but could be a little higher from KMOT to KJMS this afternoon. Wind diminish this evening and turn north to northeast tonight from east to west as a backdoor cold front pushes west through the forecast area. Expect MVFR to IFR ceilings behind the cold front, with these MVFR to IFR ceilings remaining through the remainder of the TAF period, once clouds move in. Possibly some IFR-LIFR cigs vsbys along the leading edge of the stratus as it pushes west tonight into Wednesday morning, but at this time too uncertain to add to any one TAF. Also, too uncertain for any mention of precip at any site attim. && .BIS WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE...TWH DISCUSSION...Adam AVIATION...TWH