KBIS issues Area Forecast Discussion (AFD) valid 2019-11-21T06:34:00Z 522 FXUS63 KBIS 210634 AFDBIS Area Forecast Discussion National Weather Service Bismarck ND 1234 AM CST Thu Nov 21 2019 .UPDATE... Issued at 1234 AM CST Thu Nov 21 2019 Skies continued to clear in the northwest corner of the state, and temperatures were already at zero F at Crosby. Some fog was reported at Estevan, and satellite pics indicate some fog/stratus areas developing in the clearing. The center of surface high pressure behind the departing storm system was over eastern Montana. Expect temperatures to fall even more in the northwest, Will lower min temperatures for tonight in the northwest where deep fresh snow cover exists...from the far northwest corner of Divide County to Portal (south of Estevan). Temperatures there this morning will likely reach the single digits below zero. Lowered min temps to 5 to 8 below zero...but would not be surprised if we see some locales with lows around 10 below. UPDATE Issued at 939 PM CST Wed Nov 20 2019 Skies are clearing northwest, and with deep and fresh snow cover we should see lows falling below zero across the far northwest. The threat of freezing drizzle has just about ended with the low levels not as moist as before. UPDATE Issued at 558 PM CST Wed Nov 20 2019 Brief periods of freezing drizzle are still possible across the southwest and south central where low level saturations exist with dry air above. The threat for this freezing drizzle will diminish with time this evening and overnight. The current forecast looks reasonable so far. && .SHORT TERM...(This evening through Thursday) Issued at 240 PM CST Wed Nov 20 2019 Forecast highlights in the short term period will be snow ending over my northeast with lingering drizzle/freezing drizzle southwest and south central through this evening. Currently, mid level S/WV trough extends from northern Manitoba south/southwest into northeast Montana, with an embedded wave moving east across north central North Dakota. Forcing ahead of the embedded wave and right entrance region upper jet dynamics tracking out of my northeast. Strong frontogenetical forcing will also weaken here on out this afternoon. Thus ongoing moderate snow bands now over my far northeast counties expected to rapidly diminish/push east over the next one hour. Winter weather advisory and associated special weather statement all end at 1500, and see no reason to extend any of those products. Farther south, drizzle or light freezing drizzle have been ongoing. No impacts thus far with road sfc temperatures well above freezing. Main upper level wave moves east across western and central North Dakota tonight. Lingering low level moisture southwest and south central, coupled with the associated forcing ahead of the main trough will result in a continued threat for light precipitation in the form of either light snow or light freezing drizzle. Some impacts may arise this evening as road sfc temperatures quickly fall below zero, though much depends on the extent and degree of any freezing drizzle. Will mention in the HWO and SFP for now. Northwest flow aloft for Thursday and Thursday night, with surface high pressure building over the Dakotas Thursday, then pushing off to our south Thursday night. Dry and cool for Thursday with highs in the 20s to around 30F. Return flow Thur night though lack of cloud cover should allow temperatures to fall into the teens most areas. .LONG TERM...(Thursday night through Wednesday) Issued at 240 PM CST Wed Nov 20 2019 We begin the long term period dry and mild Friday and Saturday as WAA moves into our region with a west/northwest quasi-zonal flow aloft. A couple of waves are advertised to pass through, though models continue to depict them as dry. I would suggest if you have not already put up your Christmas lights and plan to do so, this coming weekend is the time to do it. Broad ridging to our west breaks down Sunday-Monday as a 145KT upper jet streak noses into the Pacific Northwest, amplifying a long wave trough from central Canada southward across much of the central CONUS. This results in colder temperatures to surge southward out of Canada, with any precipitation chances remaining low through Monday. Uncertainty ramps up after Tuesday with a variety of solutions possible. What is more certain is colder air will stick around through the Thanksgiving Holiday and quite the active pattern developing, with a decent potential for widespread accumulating snow...somewhere and someday mid to late next week. && .AVIATION...(For the 06Z TAFS through 06Z Thursday night) Issued at 1234 AM CST Thu Nov 21 2019 High pressure across eastern Montana will move east tonight and Thursday. This will gradually bring decreasing clouds to the region late tonight and Thursday. Expect IFR to Low MVFR conditions most areas to become VFR after 12-16z. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...JV SHORT TERM...NH LONG TERM...NH AVIATION...WAA