Area Forecast Discussion
Issued by NWS Bismarck, ND
Issued by NWS Bismarck, ND
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379 FXUS63 KBIS 310339 AFDBIS Area Forecast Discussion National Weather Service Bismarck ND 1039 PM CDT Thu Jul 30 2026 .KEY MESSAGES... - Cooler but humid today, then becoming very hot again over the weekend. - Hot, dry, and windy conditions on Sunday could result in at least near-critical fire weather conditions across much of the western half of the state. && .UPDATE... Issued at 1024 PM CDT Thu Jul 30 2026 Showers and a thunderstorm or two continue to trend down and move southwards out of the area along the front. This will lead to no precipitation across the region. No updates are needed at this time as the forecast remains on track. UPDATE Issued at 626 PM CDT Thu Jul 30 2026 Shower and thunderstorms continue across the southwest and south central. Storms continue to trend down. No major updates at this time. && .DISCUSSION... Issued at 230 PM CDT Thu Jul 30 2026 Southwesterly flow is found over the northern Plains this afternoon as a shortwave traverses the upper level ridge exiting the region to the east. With the passage of this shortwave, showers and thunderstorms have developed across much of western and central North Dakota today, mostly along the associated surface cold front slowly making its way southeast across the forecast area. With the greater access to the Gulf moisture plume that this pattern allows, dewpoints are expected to rise well into the mid 60s to mid 70s this afternoon, highest across the south central. With this contributing to model MUCAPE values peaking well into the 1500 to 2500 J/KG range, and with the broad synoptic lift accentuated by 850mb jet dynamics late this afternoon and evening, at least a few stronger to marginally severe thunderstorms will be possible today, though they will need to overcome a weak 850-900mb CAP. The overall lack of shear across the area, with model 0-6KM values peaking only around 15 to 25 knots, is expected to keep any stronger storms fairly transient. As of the latest forecast cycles, short term CAMs dial into the stronger storm potential over the southwest late this afternoon, where the influence of the mid level jet is expected to be greatest, and where a weak surface low anchored to the cold front is expected to cut across before moving into South Dakota. Of note today is the potential for landspouts to develop along the slow moving cold front, with global models advertising enhanced surface vorticity along this boundary in the mid afternoon through the early evening. The area to watch would be over south central into southeastern North Dakota, including the James River Valley, where this surface vorticity is both maximized and potentially further enhanced by subsequent outflow boundary interactions from decaying storms earlier in the day. SPC has placed much of the forecast area along and south of Highway 200 into a Marginal (level 1 of 5) Risk for isolated severe thunderstorms this afternoon. Regarding potential hazards we will continue to advertise large hail up to the size of quarters, and wind gusts up to 60 MPH, while also mentioning the expectation for locally heavy rainfall where and when thunderstorms develop. High PWATs in the 1.5 to 2.0 range and warm rain processes have already contributed to rainfall totals of 1.5 to 2.5 inches across portions of the northern James River Valley this morning, where storms were fairly short lived. The developing storms this afternoon have been fairly stationary so far, which means this heavy rainfall may linger over an area for a while. We will need to monitor for potential flooding through this afternoon and evening, though CAMs continue to advertise the gradual acceleration of this system out of the forecast area through the late afternoon and evening. Otherwise, the main story through the remainder of the week is going to be the return of warmer temperatures and drier conditions as a transient upper level ridge slides across the northern Plains. While lingering zonal flow and a weak shortwave could promote some scattered storms will be possible over the northwest on Friday, the shift toward northwesterly flow will preclude any notable precipitation through the weekend. Highs each day are expected to increase, from being broadly in the 80s this afternoon, into the 80s and 90s on Friday, and back into the 90s and 100s Saturday and Sunday. Despite the lower dewpoints expected across the forecast area this weekend, some consideration for potential heat headlines must be given over the next few forecast cycles, especially as the contribution of short-term CAMs to the ensemble increases, and as the potential for compressive heating ahead of a weak cold front late Saturday through Sunday may drive temperatures across portions of the south central evening well into the upper end of the model spread. Of note during this period is the potential for near critical to critical fire weather conditions across portions of western North Dakota starting Sunday. The passage of the aforementioned weak cold front Saturday night through Sunday, then the passage of a stronger cold front Sunday through Monday, is expected to promote breezy winds in the afternoon and evening hours. With mostly prevailing dry conditions expected through this period, though the passage of the stronger cold front Sunday through Monday may promote at least low chances for showers and storms across much of western and central North Dakota, and with fuels across much of western and especially south central North Dakota having started to cure over the past few weeks, we will need to monitor trends over the next few days due to fire weather concerns. Looking further ahead, the ensemble advertises cyclonic flow aloft as a low pressure system slowly meanders across northern Canada. With this pattern, somewhat cooler weather mainly in the 70s and 80s can be anticipated, with some off and on chances for precpitation through the mid week. Beyond this period, the ensemble becomes split between a warmer and drier scenario (55 percent membership) as the upper low is dislodged further to the east and a transient upper level ridge slides across the region, and a continuation of the cooler and comparably wetter conditions (45 percent membership) as the upper level low retrogrades in place through the end of the workweek. && .AVIATION /00Z TAFS THROUGH 00Z SATURDAY/... Issued at 626 PM CDT Thu Jul 30 2026 Thunderstorms and showers continue across the southwest and portions of the James River Valley currently are not forecast to impact any TAF sites. Amendments will be made for storms if they approach any terminals. There could be some visibility reductions from thunderstorms and rain showers. Winds will continue to veer from the northeast to the south by tomorrow afternoon. VFR conditions will persist through the period. && .BIS WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE...Johnson DISCUSSION...Adam AVIATION...Johnson