916 FXUS63 KFGF 092348 AFDFGF Area Forecast Discussion National Weather Service Grand Forks ND 648 PM CDT Tue Oct 9 2018 .UPDATE... Issued at 630 PM CDT Tue Oct 9 2018 Rain area on its way northward and updated timing of rain arrival as it spreads north. Timing of rain to snow changeover is the main fcst issue with the idea of it doing so in the 09z-13z period across the area for most. Snow amounts of 3-6 inches look good for the advisory area...though as usual some slight differences in exact heavy snow placement. NAM and RAP are more JMS-GFK-ROX vs GFS seems to target more FAR-TVF-BDE. && .SHORT TERM...(This evening through Wednesday) Issued at 300 PM CDT Tue Oct 9 2018 Snow totals and winter headlines will be the main headaches for the period. Water vapor loop shows the main upper trough over CO/NM, with a kicker system digging down through OR/ID that will help push the more southeasterly trough into the Northern Plains by Wednesday afternoon. The surface low is still well to our south over KS, but will move quickly northeastward tonight into IA/southern MN and then into the Great Lake for tomorrow. There will be plenty of synoptic lift from the trough as it lifts into our area, and the models continue to indicate strong 700mb frontogenesis setting up over our area tonight into tomorrow. Rain currently moving through eastern SD will enter our southern counties this evening, pushing northward throughout the night. The main deformation band will continue over the central CWA for much of the day tomorrow, before weakening and pushing eastward during the late afternoon and evening. The biggest question is not if we will get rain and snow, which is yes, but how much snow will accumulate and what the impacts will be. GEFS plumes are still all over the place with snow amounts, ranging from less than an inch of accumulation to near 10 inches at KBDE. There will be a decent amount of cold air coming down the backside of the low pressure system, along with strong northwest winds. However, quite a bit of the QPF will be falling during the daytime hours, and there should be at least some melting as snow falls. With the melting and compaction of wet snow, think that even with 0.5 to 1.5 inch of QPF there will be a pretty broad area of 3 to 6 inches. The exception of this will be where any mesoscale banding sets up, the exact location still unknown. Could see more than 6 inches to even warning level snow amounts in that band, but again, do not know the exact location at this point. Thus, will put out a broad winter weather advisory, and highlight in the wording there will be a narrow band of heavier snow. Visibilities will also be reduced within that narrow band, although with the wet snow it will be more splattering on north facing surfaces vs blowing. .LONG TERM...(Wednesday night through Tuesday) Issued at 300 PM CDT Tue Oct 9 2018 Potent storm affecting the forecast area on Wed will see snow gradually taper off from southwest to northeast during Wed night into Thu morning, ending over north central MN by early Thu morning. Cool and breezy, but drier weather will move back into the region for Thu as temperatures remain solidly in the 30s. Zonal flow and modest warm air advection will result in some warming into the 40s on Sat as a clipper system moving out of Canada brings rain and snow chances to northeast ND and northwest MN. Overall winter weather impacts are expected to be minimal at this time. Any residual pcpn will move east during Sun with temps dipping well below average once again. Another clipper offering chances for mixed pcpn is scheduled for Tue with some hope for moderation in temps maybe to near normal by the end of next week or next weekend. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 630 PM CDT Tue Oct 9 2018 Conditions will go downhill thru the night with majorty of the areas in IFR conditions for vsby and ceilings. North winds will increase to 15 to 30 kts highest in the RRV. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...Winter Weather Advisory from 1 AM Wednesday to 1 AM CDT Thursday for NDZ008-016-024-026>030-038-039-049-052>054. MN...Winter Weather Advisory from 1 AM Wednesday to 1 AM CDT Thursday for MNZ001>009-013>017-022-023-027-028. && $$ UPDATE...Riddle SHORT TERM...JR LONG TERM...WJB AVIATION...Riddle