466 FXUS63 KBIS 142338 AFDBIS Area Forecast Discussion National Weather Service Bismarck ND 638 PM CDT Sat Oct 14 2017 .UPDATE... Issued at 633 PM CDT Sat Oct 14 2017 Surface low over IA continues to move east with lingering light rain currently exiting the southern James River Valley. All rain should be out of the area in the next couple of hours. Otherwise clear to partly cloudy skies this evening with diminishing winds. Made some minor adjustments to sky cover and pops based on latest radar and satellite. Updated latest sensible weather elements and interpolated to mid evening values. && .SHORT TERM...(This evening through Sunday) Issued at 326 PM CDT Sat Oct 14 2017 Currently...a surface low was centered over the NE/IA border with an inverted trough extending northward through eastern SD near Aberdeen, to near Jamestown. At upper levels, a trough stretched across the Canadian prairies to the western Dakotas, with its base over Wyoming and western Colorado. Upper level impulses streaming northeastward from the base across SD and into south central and southeastern ND were associated with rain showers from Wyoming across SD into southeastern ND, including some thunderstorms over eastern SD. Closer to our area, the rain showers extended mainly from near Wishek and Ashley in McIntosh County through Jamestown and the James River Valley and east. Tonight the upper level trough pushes eastward into Minnesota and Iowa by around midnight, replacing the southwest flow aloft over ND today with northwesterly flow tonight. An upper level shortwave in the northwest flow aloft will dive southeast out of Alberta, reaching northwestern ND by daybreak and moving southeast across the state before exiting the James Valley by Sunday evening. A surface cold front will accompany this shortwave, and brisk northwesterly winds will develop. Bufkit soundings indicate momentum transfer from up to H800 mb, sufficient for sustained northwest winds of 20 to 25 mph and wind gusts to 30 mph. The strongest winds will likely be in the higher elevations of southwestern ND and also along the Coteau east of the Missouri River. The rain showers should exit the James Valley early this evening. We should see gradual clearing from northwest to southeast this evening, then increasing mid level clouds from the northwest late tonight associated with the incoming upper level shortwave. Overnight lows tonight in the upper 20s and lower 30s, with highs Sunday in the 50s. .LONG TERM...(Sunday night through Saturday) Issued at 326 PM CDT Sat Oct 14 2017 Broad scale ridging over the area will bring dry, mild conditions to the forecast through much of the week, with daytime temperatures reaching the 60s. A shortwave in the flow moving across the Canadian Rockies Tuesday will allow some enhanced shortwave ridging over the US Rockies and western Plains, allowing temperatures to warm into the 70s across much of western and central North Dakota on Tuesday. By late in the week, a longwave trough pushes into the west coast. Warming ahead of this trough may bring temperatures back into the 70s on Friday. Consensus of model blends hint at this warming with highs around 70 across the southern counties. Later model runs may result in a warmer end to the week before chances of rain and cooler conditions for next weekend. && .AVIATION...(For the 00Z TAFS through 00Z Sunday evening) Issued at 633 PM CDT Sat Oct 14 2017 VFR conditions expected through the TAF period. Light rain currently south and east of KJMS will exit the forecast area. Clear to partly cloudy tonight and Sunday with only some mid and high clouds expected. Winds will diminish this evening and shift more southwest, then increase again Sunday late morning through the afternoon 15 to 25 mph from the west to northwest. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...TWH SHORT TERM...JV LONG TERM...JV AVIATION...TWH