FXUS63 KBIS 271422 AFDBIS Area Forecast Discussion National Weather Service Bismarck ND 922 AM CDT Sat Jul 27 2024 .KEY MESSAGES... - Isolated to scattered thunderstorms, some possibly severe this afternoon into this evening mainly over central and into eastern North Dakota. - Isolated to scattered thunderstorms are possible on Sunday. Some could be severe southwest and south central. - Daily low to medium chances (20% to 40%) for thunderstorms remain in the forecast Monday through Wednesday, then mostly dry Thursday and Friday. - Near to above normal temperatures continue, with highs mostly in the mid 80s to mid 90s through next week. && .UPDATE... Issued at 911 AM CDT Sat Jul 27 2024 A quiet morning continues across western and central North Dakota. For this update, just blended in the latest observations to the going forecast. UPDATE Issued at 630 AM CDT Sat Jul 27 2024 A few lingering showers over the south central into the JRV early this morning, but for the most part convection has ended until the next round this afternoon/evening. Still a lot of uncertainty in the CAMS and trend has been later and not as strong with convection over central ND. Will see if the 12Z Cams continue this trend. Only some minor adjustments to sky cover and pops this morning. && .DISCUSSION... Issued at 206 AM CDT Sat Jul 27 2024 Isolated to scattered thunderstorms highlight the forecast this weekend. Some of these could be severe but confidence remains low in the extent of severe storms both today and Sunday. Currently, a slow moving frontal boundary remains situated over the James River valley northeast into northwest Minnesota. Thunderstorms continue to train along this boundary with over northeast ND into northern Minnesota. In our neck of the woods, the convection has been rather tame with convection remaining just west of the stronger effective shear. Jamestown did receive a quick thunderstorm around 2 AM. A shortwave over western SD early this morning will lift northeast through south central into northeast North Dakota this morning. With this being an unfavorable timeframe, expect mostly shower activity with some isolated thunder this morning. Some CAMS show convection firing over eastern ND into northwest MN early to mid afternoon within an are of increasing instability. Conditions here would be favorable for strong to severe storms if convection can fire. Back to the west, over our area, there looks to be more uncertainty as to the severe thunderstorm potential. Behind the aforementioned shortwave there doesn't appear to be a significant source of forcing for ascent other than the convergence along another slow moving cold front associated with the upper level trough tracking across southern Canada. By mid to late afternoon the cold front is forecast to be situated generally from north central into southwest North Dakota. Most of the CAMS do develop at least some convection along the boundary this afternoon. However there is a pretty wide spread in where this convection develops. Some Cams show convection developing around 20-21 UTC as far west as around Dickinson. Other CAMS develop convection later (around 00-01 UTC) around Bismarck and up towards Rolla. Instability and shear will not be as strong as that over eastern ND into northwest Minnesota, yet sufficient to support a few strong to severe storms, if convection can fire. If convection would develop farther west, the threat for severe storms would be less until they reach better shear and instability over central ND. The CIN over western and central ND this afternoon is decent with some warmer temperatures aloft, especially south. There are also weak height rises west this afternoon. These limiting factors could significantly limit the extent of severe storms. Yet as mentioned earlier, most CAMS do develop at least some convection over central ND. If this does occur the main hazards would be hail to the size of golf balls and damaging winds up to 60 mph. A tornado certainly can not be ruled out, but the threat does seem rather low. The most likely scenario may be a quick landspout spinup along the front during max heating late this afternoon. The CSU-MLP shows the tornado threat situated more over northern Minnesota, rather than back over central ND. It also has a stronger signal for large hail back into central ND. Thunderstorms could linger past midnight but the threat for severe storms should diminish and/or move east of the area shortly after sunset. On Sunday a shortwave tracking through the northern/central Rockies will move into the Northern Plains. Surface low pressure over the Central High Plains will provide moisture transport from east to west along the ND/SD border. Although showers and thunderstorms can not be ruled out across western and central ND, as a northern stream wave is also approaching from the west, the severe threat for Sunday looks to be extended a bit farther west than today with southwest and south central ND the most likely areas to see a strong to severe storm. Hail up to the size of quarters and winds up to 60 mph would be the main hazards expected. SPC has a slight risk touching far south central ND, but it is situated mostly over central South Dakota. The northern extent of the marginal risk in North Dakota extends from around Hettinger to Harvey, with only a general thunderstorm risk North and west of this line. Beyond the weekend convection, it looks like the near daily chances for thunderstorms will continue Monday through Wednesday with drier conditions possibly to end the work week. Temperatures through the entire forecast period are expected to remain near or above normal with highs generally in the mid 80s to mid 90s. && .AVIATION /12Z TAFS THROUGH 12Z SUNDAY/... Issued at 630 AM CDT Sat Jul 27 2024 Thunderstorms are possible this afternoon into this evening, mainly across southern TAF sites, although KMOT could be close to convection. Convection may develop along a slow moving cold front this afternoon/evening and move east. KXWA should remain away from any convection this afternoon and evening. MVFR vsbys and gusty erratic winds are possible with any convection. Variable winds today generally 12 knots or less. && .BIS WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE...ZH DISCUSSION...TWH AVIATION...TWH