FXUS63 KBIS 210552 AFDBIS Area Forecast Discussion National Weather Service Bismarck ND 1252 AM CDT Sun Jun 21 2026 .KEY MESSAGES... - Periodic showers and thunderstorms through Tuesday, beginning in the far southwest tonight before gradually expanding northward on Sunday and eastward Sunday night. - The threat for severe weather is low this weekend through at least the middle of next week. - Temperatures will remain below average through the middle of next week, with a slight warm up favored for the end of next week. && .UPDATE... Issued at 1252 AM CDT Sun Jun 21 2026 Limited updates needed at this time. Weak radar returns in the southwest have diminished somewhat. There may be a brief lull in rain chances in the southwest before more light rain returns later tonight into Sunday morning. Overall the forecast remains on track. UPDATE Issued at 1007 PM CDT Sat Jun 20 2026 The forecast remains on track. Showers in southwest North Dakota have trended downward for now, but coverage and intensity should increase by early Sunday morning as a mid level low spins northeastward off the Bighorn Mountains. UPDATE Issued at 718 PM CDT Sat Jun 20 2026 Forecast changes for this update were focused on trending PoPs toward current observations and trends and the latest high- resolution model guidance. Scattered light showers have been falling over far southwest North Dakota since late afternoon with little to no northeastward expansion. The most noticeable trend in recent CAMs has been to keep areas from around Dickinson to the north and east dry through Sunday afternoon as the easterly low level flow rounding Canadian high pressure maintains a drier air mass. This trend has also emerged in global models, and the most recent NBM has decreased PoPs over central North Dakota. && .DISCUSSION... Issued at 204 PM CDT Sat Jun 20 2026 Not a whole lot has changed to the ongoing forecast. Upper low over eastern BC/Alberta will ever so gradually meander eastward across southern Canada and eventually down into the Great Lakes Region through the middle of next week. This will lead to daily shower and thunderstorm chances through Tuesday. Despite daily chances, there are three distinct periods with high probabilities of precipitation. The first starts as surface low pressure develops over central Montana this evening and gradually slides eastwards. Initially this produces low chances in the far southwest this evening that will become medium to high mainly across the western half of the state Sunday. The second is Monday afternoon through Monday night as the surface low begins to propagate quicker to the east and tightens up, which will result in transitory high PoPs from west to east. The third is Tuesday afternoon, especially in the north and east as the aforementioned surface low stalls. The current thinking is that the severe weather threat on any given day is low. However, if a few strong to severe storms were to develop, Sunday afternoon/evening in the northwest and Monday afternoon/early evening in the west and north central would be the most likely times and locations. That said, neither SPC nor CSU machine learning are highlighting the forecast area at this time, and even the most bullish deterministic models generally maintain marginal instability and shear. Beyond Tuesday, mostly dry conditions are favored across the forecast area through Thursday night with some minor localized exceptions. The NBM then brings the return of additional chances initially Friday, but especially this weekend. Temperatures are currently forecast to remain below average overall through Thursday, before returning to near average towards the end of next week. && .AVIATION /06Z TAFS THROUGH 06Z MONDAY/... Issued at 1252 AM CDT Sun Jun 21 2026 Mainly VFR conditions are expected through the forecast period, with some shower and thunderstorm chances in the west at times. Rest of tonight look for VFR clouds with some light rain in the far southwest. Sunday, low VFR to VFR clouds will continue to be found across the state. Some shower and thunderstorms are possible in the west, with PROB30 groups in the KXWA and KDIK TAFs. Brief MVFR conditions are possible with heavier showers or thunderstorms. Any rain showers that do form will push eastward Sunday evening, with a PROB30 group in at KMOT to account for this. Low VFR to VFR ceilings may be found at most sites Sunday evening. A breezy southeast wind will also be found at most sites through Sunday. && .BIS WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE...Anglin DISCUSSION...Telken AVIATION...Anglin