Huff Hills Snow Report

251 FXUS63 KBIS 300557 AFDBIS Area Forecast Discussion National Weather Service Bismarck ND 1257 AM CDT Sun Aug 30 2026 .KEY MESSAGES... - Showers and scattered thunderstorms expected overnight. Locally heavy rainfall is possible where thunderstorms develop. - Patchy fog is possible across much of western and central North Dakota Sunday morning. - Isolated to scattered severe storms are possible Sunday into Sunday night. Large hail and damaging winds are possible along with locally heavy rainfall. A tornado cannot be ruled out on Sunday as well. - Dry and windy conditions are forecast for Monday. Locations south and west of the Missouri River may experience near critical to critical fire weather conditions through much of Monday. && .UPDATE... Issued at 1257 AM CDT Sun Aug 30 2026 Showers and thunderstorms are starting to push in across the south ahead of a mid level upper wave. Modest shear and instability could provide for an isolated stronger storm, although a lack of mid level lapse rates, low level jet, and favorable hodo graphs should keep hail sizes mostly sub severe. Lower DCAPE should also limit the wind threat through tonight. These storms will move into a rich moisture environment, with PWATs of an inch to 1.5+ inches. Given their slow moving nature as well, localized heavy rainfall is possible tonight. Made some minor PoP adjustments based on the latest radar trends. Otherwise, any clearing ahead and behind these storms could lead to some patchy fog and low clouds. Maintained ongoing patchy fog mention as a result. UPDATE Issued at 1015 PM CDT Sat Aug 29 2026 Scattered weak radar returns and isolated thunder is found over portions of western and south central North Dakota at the time of this mid to late evening update. Coverage of both showers and thunderstorms is expected to increase overnight through Friday morning as a H7 jet develops and drops out of Saskatchewan across the forecast area. While most storms are expected to be fairly weak and embedded within the broader are of precpitation, CAMs still advertise a storm over portions of the far northwest shortly after midnight CDT. While current analysis reveals fairly robust CIN across that, if a storm manages to develop and tap into the increasing bulk shear shear across that area it may be able to produce marginally severe hail and wind. The window for this development is expected to be fairly brief and thus overall predictability is low, but we will continue to monitor these model trends as we head into the early overnight period. Also of note is the potential for locally heavy rainfall overnight. Any storm that does develop is expected to be fairly efficient rain producers, and with high PWATs around 1.5" to 2.0" across the area and the overall slow progression of these storms, it wouldn`t be overly surprising to see rainfall rates approach 1"/hr over portions of the northwest or the south central. We will need to monitor for flooding potential overnight. Regarding forecast updates, opted to blanket much of western and central North Dakota with patchy fog overnight after considering the ample near surface moisture behind the precipitation and the light south easterly surface winds. UPDATE Issued at 645 PM CDT Sat Aug 29 2026 Showers and a few isolated thunderstorms can be found over portions of western and central North Dakota at the time of this early evening update. At the moment, thunder is generally restricted to the far northwest where an H5 divergence max can be found. These storms have been fairly pulsey so far, with better shear found further to the south. Increasing cloud cover and the loss of peak heating is generally anticipated to limit thunderstorm activity across the northwest as we head into the mid to late evening. High low level lapse rates and decent DCAPE across this area does mean that we will have to watch this area for gusty winds over the next few hours. In the south central, an area of clearing in the cloud layer is helping to destabilize as we head into the early evening. With higher dewpoints in the upper 60s to lower 70s and temperatures well into the 80s at this time, analysis indicates decent MUCAPE values of around 2500-3000 J/KG along and south of I-95. With moderate shear also found across this area (around 40 to 45 knots), the potential for a stronger to severe storm to develop is expected to be somewhat higher here. That said, there doesn`t appear to be much forcing across the region to get things going this late in the day. Convection further south in SD is likely associated with H3 speed max analyzed over that area, while the convection further west in Montana is developing an surface trough/occluded front that isn`t expected to make into our area until late tonight. Thus, while we will continue to monitor conditions as we head into the evening, the overall potential for a stronger to severe thunderstorm is expected to be limited. With this update, have blended in the latest short-term guidance in the PoPs to increase coverage of precipitation in the northwest and south central this evening and tonight. Otherwise, the forecast remains in good shape. && .DISCUSSION... Issued at 154 PM CDT Sat Aug 29 2026 Early this afternoon, a broad and strong mid/upper ridge was centered over the southern and central plains with a vigorous deep layer trough progressing eastward out of the PNW. Out ahead of this trough, several perturbations were noted within southwesterly upper flow over the northern CONUS. Despite the copious amounts of upper level cloud cover across the region, modest destabilization is occurring this afternoon across North Dakota out ahead of shallow shortwave trough located over the central Rockies. As forcing for ascent arrives later this evening into tonight, isolated to scattered showers and storms are expected to develop across western North Dakota and gradually work their way eastward. Continued development and/or persistence of this activity may also be supported by subtle mid-level WAA overnight into early Sunday morning. The greatest coverage of showers and storms will likely be along and south of I-94, especially given that better forcing for ascent appears to be trending further south for tonight into early tomorrow morning. Activity this evening into tonight will struggle to contend with widespread convective inhibition, and chances for a couple of isolated severe storms before 06Z appears to be waning given the latest short term guidance. However, elevated instability along the axis of mid-level WAA overnight into early Sunday morning will be fairly decent (generally around 1500-2000 J/kg of MUCAPE). Effective shear around 30 knots could support some organized elevated convection capable of hail up to ping pong ball size. Damaging wind gusts appears less likely, but an isolated instance of a 50-60 mph wind gust cannot be ruled out overnight and early Sunday morning. Sunday appears to be quite the complicated setup for potential severe weather across North Dakota. A strong and deep upper trough will lumber eastward across southern Alberta during the day on Sunday with a sharp lobe of vorticity expected to round the southern end of the trough and kick out across eastern Montana and North Dakota. This should provide significant forcing for ascent across the northern CONUS for widespread showers and thunderstorms Sunday afternoon through Sunday night. Guidance has generally backed off the idea that shower and thunderstorm activity will be ongoing through much of the morning hours on Sunday. This seems a little off given the amplitude of upper level diffluence that will be overspreading the region as early as Sunday morning, but it`s likely other factors are at play such as subsidence behind any activity the occurs late tonight into early Sunday morning. With short-range models backing off on morning convection across the state, this leaves the door open for potent destabilization across the forecast area. Model soundings across the warm sector Sunday afternoon show an uncapped airmass with ample instability around 2000-2500 J/kg. Shear will also be conducive for some organized convection with 0-6 km shear around 25 to 35 knots. Given the amount of synoptic ascent, the sharpness of the surface frontal boundary, and shear vectors parallel to said boundary, the expectation is for thunderstorms to rapidly grow upscale. With a linear storm mode favored, the main concern will be damaging wind gusts around 60-70 mph. At this time, it appears the hail threat will be limited to the first couple of hours after convective initiation when storms still have the opportunity to be semi-discrete. Lastly, a tornado or two cannot be ruled out where surface winds will be slightly back along a weak warm front draped across the state. The primary difference in the guidance at this point is the location of the warm sector. Solutions, like the HRRR and ARW, show a psuedo-dryline developing in the vicinity of the US-83 keeping warm, humid air east of this corridor. Meanwhile, other solutions, like the NAM and NSSL, show this moisture gradient along the ND/MT state line. This may have an impact on the intensity of convection early, perhaps modestly suppressing thunderstorm activity in the drier solution. However, the overall severe threats remain the same regardless of which scenario plays out. Monday also appears to be a somewhat busy day for much of North Dakota, though more for wind and fire weather concerns. The surface low and upper low are forecast to become more vertically stacked over Saskatchewan, and a tight pressure gradient is expected across southern Saskatchewan/Manitoba into much of North Dakota. Mostly clear skies should allow for deep mixing across these areas, and uniform flow in the boundary layer should allow for efficient mixing of stout winds to the surface. Model guidance suggests 850 mb winds could be in the neighborhood of 45 to 50 knots, mainly across northern North Dakota. Should these winds mix down to the surface, it`s possible some locations along and north of US-2 could experience 45 to 55 mph wind gusts during the day on Monday. It`s possible a wind advisory may be needed for these areas late Monday morning into Monday afternoon. Further south, the expectation is for wind gusts to be in the 30 to 45 mph range. RH values will generally be around 20-30% south and west of the Missouri River. This along with the aforementioned breezy conditions will support near critical to critical fire weather concerns across southwest North Dakota. As the surface low gradually weakens and lifts northeast, the pressure gradient will begin to relax by late afternoon. Thus, breezy conditions should generally come to an end by sunset Monday evening. Periodic chances for showers and storms remains in the forecast from Tuesday through the end of next week. Mid to long range guidance continues to be on board with a series of systems traversing the northern plains around mid/upper ridging remaining over the central and southern plains. The best chances for showers and storms next week will likely be Wednesday night into Thursday morning as a stout upper trough is forecast to eject into the northern plains. Exact details remain a bit murky this far out, so stay tuned for updates to the forecast for this time period over the next few days. && .AVIATION /06Z TAFS THROUGH 06Z MONDAY/... Issued at 1257 AM CDT Sun Aug 30 2026 MVFR to VFR conditions could be found tonight as an initial round of showers and thunderstorms lifts across the forest area. Most sites have a TEMPO or PROB30 group for thunderstorms to account for this. Any clearing ahead or behind these storms could lead to some IFR to MVFR ceilings and perhaps visibilities with patchy fog. Confidence in this occurring is low, although KMOT and KJMS are already seeing some lower clouds trying to form. After the initial round of showers and thunderstorms moves through Sunday morning, MVFR to VFR ceilings will prevail across much of the area through the day. Later in the day through the evening another round of thunderstorms looks to push from west to east, bringing MVFR and isolated severe conditions. Prevailing and PROB30 groups for these storm chances were used at most sites. A south southeast wind will be found for Sunday, changing to a westerly wind later Sunday through Sunday night as a cold front moves through. && .BIS WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE...Anglin DISCUSSION...JC AVIATION...Anglin