FXUS63 KBIS 222002 AFDBIS Area Forecast Discussion National Weather Service Bismarck ND 302 PM CDT Sat Aug 22 2026 .KEY MESSAGES... - Low to medium chances for showers/thunderstorms push over the area at various times late tonight through Sunday night, possibly lingering over parts of the area into Monday. - A few storms may be strong to severe over southwest and south central North Dakota Sunday, far western North Dakota Sunday night, and central and eastern North Dakota on Monday. - Near to slightly above average temperatures remain in the forecast through the upcoming week. && .DISCUSSION... Issued at 233 PM CDT Sat Aug 22 2026 Current surface analysis places broad high centered over southern Manitoba into the eastern Dakotas, while a low is starting to develop to the lee of the Rockies. Upper level analysis places high over New Mexico, with ridge running northward generally to the lee of the Rockies. Over our area, light winds remain over most locations, though are becoming southeasterly and increasing over our southwest in response to the developing low. For tonight, surface high pushes east with south-southeasterly winds on the increase, particularly over western areas. On Sunday, south-southeasterly winds will continue over the area resulting in increasing low-level moisture and higher humidity values. Of note will be increasing instability values over southwestern into south central North Dakota, with some guidance noting CAPE values exceeding 2000 J/Kg, though guidance is keeping deep layer shear marginal and also possibly capped given the possible limited heating due to mid-level cloud cover. Therefore, will keep severe threat marginal at this point focused mainly over the southwest/south central. As we get into Monday night, the next thunderstorm threat pushes in from Montana late as another short wave makes its approach, again posing a marginal severe threat. Chances then spread east through the day on Monday as the wave and surface trough/front slide easterly. Again, guidance is suggesting elevated instability as we get into primarily central/eastern North Dakota with marginal shear, but then timing of this system comes into play. Therefore, will continue to focus on the marginal threat. On Tuesday, western ridge remains in place but a very compact short wave/low slides down the face of the ridge, but at this point only looks to graze our northeastern areas. Therefore, most locations are expected to remain mild and dry, though some precipitation chances will be in place mainly around the Turtle Mountains. Ridge to the west slowly creeps east and remains the dominating factor keeping temperatures near to above average through the remainder of the forecast, though a few waves pushing through do bring occasional precipitation chances. && .AVIATION /18Z TAFS THROUGH 18Z SUNDAY/... Issued at 144 PM CDT Sat Aug 22 2026 Afternoon fair weather cumulus over the James River Valley is resulting in some low end VFR ceilings, though should erode later today into this evening. South-southeast winds will be on the increase overnight into Sunday morning. Over western North Dakota, scattered showers and thunderstorms will be possible late overnight into Sunday morning, possibly affecting the KDIK and KXWA terminals. Given high confidence, have mentioned in the KDIK TAF. && .BIS WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...JJS AVIATION...JJS