438 FXUS63 KDLH 240250 AFDDLH Area Forecast Discussion National Weather Service Duluth MN 850 PM CST Sat Feb 23 2019 .UPDATE... Issued at 850 PM CST Sat Feb 23 2019 More reports of freezing drizzle have developed this evening and will likely adjust the start time of the Winter Advisory for the rest of northern Minnesota to start at 9 pm. We also plan on issuing a Winter Weather Advisory for the North Shore and delaying the start of the Blizzard Warning until 15Z when we expect the strong winds to develop. We hope to get updates out shortly. UPDATE Issued at 834 PM CST Sat Feb 23 2019 The forecast is on track as we expect heavy snow to fall over portions of northern Wisconsin, with snowfall *rates* of 1 to 3 inches per hour developing late evening and overnight. The highest snowfall amounts are still expected over Price, Iron, Ashland, and Sawyer Counties with amounts tapering off to 1 to 3 inches over most of northern Minnesota. The Arrowhead will see amounts from 2 to 5 inches. Radar shows heavy snow was moving toward our Wisconsin zones as of 830 PM. There was still some light snow and freezing drizzle in spots over Northland but snow will become the dominant precipitation type as the evening/overnight period progresses. && .SHORT TERM...(This evening through Sunday) Issued at 340 PM CST Sat Feb 23 2019 The main focus for tonight through Sunday continues to be on a powerful winter storm that will impact the eastern portions of the forecast area, and bring heavy accumulating snow and strong northwest winds. A potent mid-level shortwave and an attendant surface low pressure system, currently located over eastern KS/western MO, will strengthen over eastern Iowa this evening, and translate northeastward over northern Lake Michigan early Sunday morning. Very strong dynamics will be associated with this system, with upper-level divergence, as well as impressive isentropic ascent through much of the column. The area of low pressure is progged to deepen to the tune of 1 mb pressure falls per hour, per both the 23.12z GFS and ECMWF models. The overall forcing with this system is quite impressive, per the values of the Thaler QG omega progs, with surprising consistency between the GFS, NAM, and ECMWF models. The strongest forcing will remain over northern Wisconsin tonight, which is where the heaviest snow accumulation is also expected. The other aspect of this system that is of concern is blowing and drifting snow, which will make for some difficult travel Sunday morning. The main areas of impact will be over north- central Wisconsin and into the Minnesota Arrowhead, where a combination of moderate to heavy accumulating snow and strong northwest winds will lead to treacherous travel conditions. In total, snow accumulations will be their heaviest over northwest Wisconsin, where between 5 to 14 inches of accumulation is possible, with between 2 to 5 inches of accumulation over the Minnesota Arrowhead. However, the main concern over the Arrowhead will be blizzard conditions due to very strong northwest winds. Gusts should range between 35 to 45 mph along the North Shore, perhaps up to 50 mph. Even with lighter snow accumulations, the concern will be for impactful blowing and drifting snow, particularly since the winds will be perpendicular to Highway 61. With these factors considered, decided to issue a Blizzard Warning for Sunday. In addition, we decided to issued a Winter Weather Advisory for the rest of northeast Minnesota since blowing and drifting snow will also be an issue, but not expecting to be quite as favorable as along the North Shore. The accumulating snow will fall at a very rapid pace tonight, especially over Price and Iron counties, with one to two inch per hour rates possible, between midnight tonight and 6 AM Sunday morning. Travel will likely become impossible in some spots in these counties. After sunrise Sunday, chances of snow will slowly taper off throughout the day, but should linger along the South Shore due to increasing chances of lake effect snow. Cold air advection behind the quickly departing low pressure system will bring more favorable 850 mb temperatures, which should linger some additional snowfall, especially along the higher elevations of northern Iron county. Due to this cold air advection increasing throughout the day Sunday, high temperatures will occur in the morning hours, with slowly cooling temperatures throughout the day. This cold air advection will likely lead to bitterly cold wind chills Sunday night and Monday morning. .LONG TERM...(Sunday night through Saturday) Issued at 318 PM CST Sat Feb 23 2019 The parent low from Sunday's storm will quickly move into western Quebec Sunday night, bringing an end to the snow across the Northland. However, snow may linger along the South Shore of Lake Superior through the night and any additional accumulations will be minor. Colder air will be moving into the region with the breezy northwest winds and temperatures at 850mb will be around 25C below zero, with even colder air north of the Canadian Border. If this even colder air can work just a bit further south, or clouds break up faster than anticipated, lows Monday morning may come in lower. We've already lowered them a few degrees into the 15 to 20 below range as is across Minnesota where most of the clearing is expected to occur. These temperatures, coupled with the still gusty winds, will most likely require a wind chill advisory for Sunday night/Monday morning. Cold high pressure will then move in for Monday and Monday night. Skies will be mostly sunny, but a cold air mass will only result in highs in the single digits and lows Monday night in the teens below zero with single digits below zero along the North and South Shore. Heading into Tuesday, a shortwave will approach the Northland. This will lead to snow chances Tuesday afternoon into Wednesday morning. The 23.12 GFS remains the fastest and strongest with this wave, while the 23.12 Euro is much weaker and slower. The 23.18 NAM seems to be trending towards the Euro solution at this time. Have kept chance pops in place, but this could change in the coming days. High pressure then returns for the latter half of the week. Heading into next weekend, a strong upper low looks to be in the vicinity of Manitoba while another strong low approaches the Pacific Northwest. The 12Z suite of models are phasing these two lows together and ejecting the more southerly low across the Rockies and into the Central/Northern Plains. Given the drastic change from the 00Z suite where the ECMWF did not phase the systems together, opting to keep a blended approach at this time. However, this will bear watching as it has the potential to be the next shot at potentially significant snow across the area. && .AVIATION...(For the 00Z TAFS through 00Z Sunday evening) Issued at 613 PM CST Sat Feb 23 2019 Surface low pressure in northwest Missouri will deepen rapidly overnight as it moves to northern Lake Michigan by 12Z Sunday. There will be some areas of light snow or freezing drizzle this evening but snow will spread north, especially over northern Wisconsin. The snow will be very heavy late evening and overnight with rates of 1 to 2 inches per hour likely over Price, Iron, and parts of Sawyer and Ashland Counties. A mix of MVFR and IFR ceilings will occur tonight but improve to MVFR and low VFR Sunday afternoon. The visibility will from to 1 to 4 miles for most areas but be a quarter to half over northern Wisconsin later tonight into Sunday morning. In addition to the precipitation, strong northwest winds will develop as the low departs. Gusts of 30 to 50 mph will be possible with the highest gusts close to Lake Superior. && .PRELIMINARY POINT TEMPS/POPS... DLH 19 21 -13 4 / 90 40 0 0 INL 13 15 -20 2 / 40 50 0 0 BRD 13 15 -17 4 / 30 0 0 0 HYR 22 25 -13 6 / 100 90 0 0 ASX 25 27 -7 7 / 100 100 30 0 && .DLH WATCHES/WARNINGS/ADVISORIES... WI...Winter Storm Warning until 6 PM CST Sunday for WIZ002-003- 007>009. Winter Storm Warning until 9 PM CST Sunday for WIZ004. Winter Weather Advisory until 6 PM CST Sunday for WIZ001-006. MN...Winter Weather Advisory from midnight tonight to 6 PM CST Sunday for MNZ010>012-018-019-025-026-033>038. Blizzard Warning from midnight tonight to 6 PM CST Sunday for MNZ020-021. LS...None. && $$ UPDATE...Melde SHORT TERM...JTS LONG TERM...BJH AVIATION...Melde