306 FXUS63 KDLH 031625 AAB AFDDLH Area Forecast Discussion...UPDATED National Weather Service Duluth MN 1025 AM CST Sat Feb 3 2018 .UPDATE... Issued at 1025 AM CST Sat Feb 3 2018 Slowed the progression of snow across our southern zones this afternoon. Still think the snow totals are on track, but regional radar mosaic and high-resolution models suggest most of the accumulation this afternoon rather than this morning. Other than adjusting the timing of the snow accumulation and raising POPs this afternoon, no significant changes made with this update. && .SHORT TERM...(Today through Sunday) Issued at 404 AM CST Sat Feb 3 2018 The focus remains on today's snow across the Northland. Only small changes were made to the snowfall forecast, and no additional winter weather headlines. The most significant change was to refine the ending times of the current winter weather advisories by trimming off 3 hours since it appears most of the snow will end by the late this afternoon or by this evening. Also issued wind chill advisories for tonight's cold weather. Snow will spread in from the west through the Northland this morning and afternoon, bringing a quick 2 to 4 inches to many areas from central MN through northwest WI by late this afternoon or early this evening. This light and fluffy snow is anticipated to cause a period of difficult driving conditions because of slippery roads. The snow will be caused by large-scale forcing for ascent and mid-level frontogenetical forcing associated with an area of low pressure that will move from the Northern High Plains early this morning to Iowa by late this afternoon. The greatest forcing and snowfall will be over northwest Wisconsin, with many areas forecast 3 to 4 inches. The snow will quickly taper off from west to east this afternoon and evening as the low and its forcing shift to the south and east, and as colder and drier air filters in from the north. Lingering light snow and lake effect snow across far northern Wisconsin tonight could see areas near the Lake, like northern Iron County, get up to a total of 5 inches when all is said and done. High pressure will build into the region from the west and north tonight and Sunday, bringing colder and drier air. It should get much colder across far northern MN tonight, in comparison to central MN to northwest WI, thanks to late night clearing, while clouds should linger farther south. Expect lows ranging from as cold as 20 to 25 below zero near the Canadian border tonight to as warm as 5 to 10 below zero across northwest Wisconsin. Very cold wind chills of 20 to 35 below zero are forecast across central and northeast MN and far northwest WI tonight, and these cold wind chills will linger through Sunday morning. Frostbite can occur to exposed skin in as little as 20 to 30 minutes in this cold weather. Sunday will remain a very cold day, even after some improvement of the wind chills by the afternoon. Expect brisk westerly winds with highs only in the lower single digits above zero, and afternoon widespread wind chills of 5 to 15 below zero. On the bright side, pun intended, we can expect plentiful sunshine during the day for much of the day. .LONG TERM...(Sunday night through Friday) Issued at 404 AM CST Sat Feb 3 2018 A persistent long wave trough over the central and eastern CONUS dominates the long term portion of the forecast, with shortwaves within the flow producing waves of snow moving across the Midwest through the period. It also means we will have generally near to below normal temperatures through the period. Sunday night and Monday a shortwave moving across Ontario will bring a chance of snow to Ontario, but should stay out of the forecast area. As the wave passes, trajectories may shift northerly enough to bring some lake effect snow into the Bayfield peninsula early Monday morning, but confidence is not very high and have kept to slight chances. The associated cold front is not very strong but the already existing and incoming airmass are cold and temperatures are below normal, with highs between 5 and 15 above. Ridging builds into the area at the surface for Monday night and Tuesday night, and with the existing cold airmass, fairly fresh snow cover and likely clearing skies have pushed down the min temperatures both nights. For now have the coldest values in the 15 to 20 below range, but would not be surprised if these need to be lowered into the 20 to 25 below range if the ideal conditions materialize. Models begin to show some pretty major discrepancies in their handling of the shortwaves by Wednesday, with some pretty big differences in the snow/no snow question and on resulting temperature trends. For now we have some small chances for snow on Wednesday through Friday, as we are sitting close to the baroclinic zone and weak clippers are depicted moving through the flow. Between this and the usual moderation towards climatology seen in the models, there is a slow warming trend in the forecast temperatures through the end of the forecast, but expect that we will be lowering temperatures for at least some of those periods as we get a better indication of shortwave timing and trajectory. && .AVIATION...(For the 12Z TAFS through 12Z Sunday morning) Issued at 542 AM CST Sat Feb 3 2018 A potent clipper system will bring a period of snow to the region, along with IFR/LIFR conditions. Snow is just spreading into the region as of issuance time, so expect a gradual deterioration in conditions through 15z, with the worst conditions expected from 15z to 21z and mainly for KBRD, KHYR and KDLH. KHIB and KINL to remain no worse than IFR and MVFR respectively. A gradual return to VFR from west to east can be expected by 06z tonight. Winds may increase to 10-15kts as the snow is tapering off, but then should also decrease again around 06z. && .PRELIMINARY POINT TEMPS/POPS... DLH 13 -13 3 -9 / 100 30 0 0 INL 2 -23 1 -13 / 40 0 10 10 BRD 13 -13 4 -9 / 100 10 0 0 HYR 16 -8 5 -9 / 100 40 10 0 ASX 15 -4 6 -2 / 100 70 10 10 && .DLH WATCHES/WARNINGS/ADVISORIES... WI...Wind Chill Advisory from midnight tonight to noon CST Sunday for WIZ001. Winter Weather Advisory until 6 PM CST this evening for WIZ001>004-006>009. MN...Wind Chill Advisory from 9 PM this evening to noon CST Sunday for MNZ010>012-018-019-025-026. Winter Weather Advisory until 3 PM CST this afternoon for MNZ035- 036. Wind Chill Advisory from midnight tonight to noon CST Sunday for MNZ020-021-033>038. Winter Weather Advisory until 6 PM CST this evening for MNZ037- 038. LS...None. && $$ UPDATE...Huyck SHORT TERM...Grochocinski LONG TERM...LE AVIATION...LE