FXUS63 KBIS 121516 AFDBIS Area Forecast Discussion National Weather Service Bismarck ND 1016 AM CDT Sat Apr 12 2025 .KEY MESSAGES... - A storm system will bring widespread medium to high chances (60-95%) for rain tonight through Sunday night, with precipitation chances decreasing through Monday. Colder temperatures and gusty winds will also accompany this system Sunday and Monday. - Some snow may mix in with the rain Sunday night through Monday morning, with little if any impacts. - Dry conditions with temperatures trending warmer are forecast towards the middle of next week, followed by cooler temperatures and chances for precipitation to end the week. && .UPDATE... Issued at 959 AM CDT Sat Apr 12 2025 This mornings showers have moved across the James River Valley into eastern North Dakota. Another shortwave is traversing the quasi-zonal flow producing showers in eastern Montana. Cloud bases remain elevated around 10kft with a dry layer aloft hindering evaporating precipitation out west resulting like virga. No updates are need to the current forecast as the forecast remains on track. UPDATE Issued at 639 AM CDT Sat Apr 12 2025 Updated POPs and sky cover for this morning, otherwise edits to the forecast were minor with this product issuance. && .DISCUSSION... Issued at 415 AM CDT Sat Apr 12 2025 Currently, quasi-zonal flow aloft as a mid level S/WV trough moves east across south central Canada, which deamplified an upper ridge over our region the past 12-18 hours. Lead embedded impulses originating out of a Pacific Northwest mid level trough continue to generate elevated showers across western and central North Dakota early this morning, mainly along and west of a frontal boundary draped across central ND. While doubtful much of this moisture is reaching the sfc with cloud bases at or above 8-10K ft AGL, a few observing sites have reported Trace amounts of moisture, so will maintain some low POPs for this activity for a few more hours this morning. Mainly dry today ahead of a storm system set to impact our region tonight through Mon. Winds will be easterly and much lighter compared to the past few days, with temperatures still above normal in the mid 60s to low 70s. Aforementioned Pacific NW trough will approach the Northern Rockies during the day today, then will close off as it continues east-southeast across the Rockies and into the Dakotas tonight through Sunday night. Lead embedded impulses may bring some light precipitation to the west and parts of central ND during the day today, with the main forcing arriving tonight into the day Sunday. Initial wave of elevated POPs will spread from west to east this evening and late tonight, as a sfc trough/frontal boundary advances eastward across western and into central ND. A few t-storms may accompany this boundary over our far south. Up to half an inch of rainfall will be possible through tonight. Mid level low then moves into western ND Sunday morning, with the better precipitation chances pivoting north into northern areas of the state as dry air wraps around the low into my southern counties. As the mid level low continues into eastern ND Sun aft/eve, wrap around moisture along with this feature's TROWAL will then see precip chances increase southward again, encompassing most of western and central ND. The heavier QPF amounts remain favored across northwest and north central North Dakota, where the best upper level forcing coincides with low/mid level frontogenesis. This area will also see the longer duration of precpitation, where a quasi- stationary/slowly east moving inverted sfc trough axis will be located. Latest WPC QPF increased, with around an inch or more of much needed rainfall across the north. QPF also increased farther south, now looking at a quarter to half an inch of moisture, which will depend on any convective activity later today and tonight, and how far south the wrap around moisture moves later Sunday and Sun night. Still looking at a potential rain/snow mix Sun night/Mon AM as colder air is pulled south in the wake of the mid level low. Still not expecting any impacts with this at this time. This initial upper low moves off to the east Sunday night, followed by another embedded S/WV in northerly flow aloft during the day Monday. Resultant weather will see precipitation chances and coverage decreasing Sun night west to east, with continued scattered showers possible through the day Monday. Along with colder temperatures and widespread precipitation, winds will increase Sunday and continue through Monday as gradient forcing increases. 850mb jet on the backside of the mid level low will bring the stronger winds on Sunday to southwesterly ND. Models differ on available mixing, so for now opted not to issue any wind headlines for this period. Will mention the possible strong winds in the HWO for now. Another windy day with potential headlines on Monday as the aforementioned secondary S/WV slides south across the region, maintaining strong gradient forcing and decent lapse rates. Ensembles are favoring a transitory mid level ridge Tue and Wed, which would result in dry weather and warmer temperatures. Thereafter, uncertainty increases, mainly focused on the eventual evolutions of an area of upper level low pressure over Alaska and another low off the southern California coast early next week. NBM has a cooling trend to end the week, along with a period of elevated POPs Wed night through Thu night. && .AVIATION /12Z TAFS THROUGH 12Z SATURDAY/... Issued at 639 AM CDT Sat Apr 12 2025 VFR conditions with mid to high clouds expected through Sat afternoon across western and central North Dakota. Later today, and especially for tonight, cloud levels will slowly drop but are expected to remain VFR through this evening. Low VFR expected west along with increasing chances for rain, including both KXWA and KDIK. Better chances for rain spread across the area later tonight and through Sunday, along with MVFR cigs likely at all terminals. Winds will turn easterly today at 10 to 15 kts. && .BIS WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE...Johnson DISCUSSION...NH AVIATION...NH