Subj : Area Forecast Discussion For Tri Cities, TN/VA To : All From : Sean Dennis Date : Wed Jan 28 2026 19:00:02 441 FXUS64 KMRX 282304 AFDMRX Area Forecast Discussion National Weather Service Morristown TN 604 PM EST Wed Jan 28 2026 ....New AVIATION... ..KEY MESSAGES... Updated at 602 PM EST Wed Jan 28 2026 - It will be dry but temperatures will remain below normal today through Thursday. - Snow is increasingly likely Friday afternoon through Saturday, especially in the eastern and northeastern portions of the region. - Arctic cold will return for the weekend. ..DISCUSSION... We remain under broad eastern CONUS troughing aloft, with surface high pressure currently over our region. This set up will keep us dry but with below normal temperatures through Thursday night. By Friday, models are in general agreement that a strong short wave will be diving southeast out of the Plains, cutting off by Saturday as it tracks over our area and then lifting off to our northeast Sunday. A weak surface low pressure system is forecast to develop near the northern Gulf and then move east and offshore the SE coast before strengthening rapidly as it tracks to the northeast off the East Coast. This system will bring at least some light snow to the area, and in this case precipitation type is not in question but the uncertainty lies in how much snow will fall. Right now it appears we will have light snow begin to show up Friday especially north as we see weak isentropic lift out ahead of the main system. Then, as the upper low approaches and the upper jet to its south noses in, we will see a period of upper divergence that will enhance snow chances. Of course, the exact track of the upper low and the surface low to our SE and E will be critical, and the models often struggle with these details even just a few days out. Right now, the best chances for significant snow accumulations look to be over our eastern and northern areas. Currently, NBM probability data shows around a 40% to 60% chance of 72 hour snowfall exceeding 4 inches by Sunday morning across our northern and central mountains as well as eastern portions of the NE TN valley and SW VA, and a 20% to 50% chance of exceeding 2 inches of snow across much of the central valley, northern Plateau, and western portions of NE TN. Orographically enhanced snow showers may linger into Sunday across the normally favored terrain as well. The other story for the weekend will be the cold. Another surge of arctic air will rush in on north and northwest winds, and high temperatures Saturday will struggle to get above the lower 20s even in the valleys. Low temperatures Saturday night will be in the single digits in most areas. Wind chill values will dip into the single digits in the valleys with well below zero values at times in the higher terrain as well Friday night through Saturday night. Sunday will likely see temperatures remaining below freezing for nearly all of the area, and Sunday night will to be very cold as well. Models are in general agreement that we will see height rises aloft and gradually moderating temperatures Monday through Wendesday. There is poor agreement on additional waves that may bring precipitation, but there is at least a modicum of agreement for more precipitation chances arriving by Wednesday. && ..DISCUSSION... We remain under broad eastern CONUS troughing aloft, with surface high pressure currently over our region. This set up will keep us dry but with below normal temperatures through Thursday night. By Friday, models are in general agreement that a strong short wave will be diving southeast out of the Plains, cutting off by Saturday as it tracks over our area and then lifting off to our northeast Sunday. A weak surface low pressure system is forecast to develop near the northern Gulf and then move east and offshore the SE coast before strengthening rapidly as it tracks to the northeast off the East Coast. This system will bring at least some light snow to the area, and in this case precipitation type is not in question but the uncertainty lies in how much snow will fall. Right now it appears we will have light snow begin to show up Friday especially north as we see weak isentropic lift out ahead of the main system. Then, as the upper low approaches and the upper jet to its south noses in, we will see a period of upper divergence that will enhance snow chances. Of course, the exact track of the upper low and the surface low to our SE and E will be critical, and the models often struggle with these details even just a few days out. Right now, the best chances for significant snow accumulations look to be over our eastern and northern areas. Currently, NBM probability data shows around a 40% to 60% chance of 72 hour snowfall exceeding 4 inches by Sunday morning across our northern and central mountains as well as eastern portions of the NE TN valley and SW VA, and a 20% to 50% chance of exceeding 2 inches of snow across much of the central valley, northern Plateau, and western portions of NE TN. Orographically enhanced snow showers may linger into Sunday across the normally favored terrain as well. The other story for the weekend will be the cold. Another surge of arctic air will rush in on north and northwest winds, and high temperatures Saturday will struggle to get above the lower 20s even in the valleys. Low temperatures Saturday night will be in the single digits in most areas. Wind chill values will dip into the single digits in the valleys with well below zero values at times in the higher terrain as well Friday night through Saturday night. Sunday will likely see temperatures remaining below freezing for nearly all of the area, and Sunday night will to be very cold as well. Models are in general agreement that we will see height rises aloft and gradually moderating temperatures Monday through Wendesday. There is poor agreement on additional waves that may bring precipitation, but there is at least a modicum of agreement for more precipitation chances arriving by Wednesday. && ..AVIATION... (00Z TAFS) Issued at 602 PM EST Wed Jan 28 2026 Northerly to westerly winds will decrease this evening with the strongest winds expected to be at TRI. While LLWS was not included, winds near or above 2,000 feet AGL will reach around 30 kts from the northwest, which could still impact smaller aircraft. Throughout the day on Thursday, winds will be from a similar direction but lighter than what was seen today. && ..PRELIMINARY POINT TEMPS/POPS... Chattanooga Airport, TN 22 42 26 43 / 0 0 0 20 Knoxville McGhee Tyson Airport, TN 20 39 25 40 / 0 0 0 30 Oak Ridge, TN 19 38 24 40 / 0 0 0 30 Tri Cities Airport, TN 14 34 21 37 / 0 10 0 50 && ..MRX WATCHES/WARNINGS/ADVISORIES... NC...NONE. TN...NONE. VA...NONE. && $$ DISCUSSION...99 AVIATION...BW --- MBSE BBS v1.1.7 (Linux-x86_64) * Origin: Outpost BBS * Johnson City, TN (618:618/1) .