486 FXUS63 KLMK 200108 AFDLMK Area Forecast Discussion National Weather Service Louisville KY 808 PM EST Wed Feb 19 2025 .KEY MESSAGES... * Another round of snow tonight could produce a half inch up to an inch across the area by Thursday morning. * Very cold temperatures are expected after the winter storm. Wind chills below zero will be possible tomorrow morning. With single digit lows for Friday morning. * Mostly dry weather through the weekend into early next week. Temperatures will rise above freezing Friday or Saturday, with above normal temps next week. && .UPDATE... Issued at 807 PM EST Wed Feb 19 2025 Swaths of light snow have begun to develop this evening as slightly deeper moisture advects into the region from the west ahead of a mid- level vorticity maximum. Moisture remains fairly shallow according to the most recent SDF ACARS soundings, but will deepen over the next 1-2 hours. The main window for light snow tonight is from now (8 pm) through 3-4 am. A dusting will be possible in most places, with up to a fluffy inch in localized spots. This snow will likely make any previous clear roads slick once again. The current Winter Weather Advisory looks good, with no changes planned at this time. Temperatures are hovering right around 20 degrees, with wind chills in the single digits to teens. It will be a very cold night, with a bitter 10 mph breeze out of the NW. Wind chills will bottom out around 0 to -5 tomorrow morning, and the Cold Weather Advisory also looks good with no changes planned at this time. && .SHORT TERM /THROUGH THURSDAY/... Issued at 309 PM EST Wed Feb 19 2025 Closed upper low over the Upper Midwest will drop into the Ohio Valley tonight into the early morning of tomorrow. A mid-level vort max will pinwheel around the base of the upper low and across southern IN and central KY later this evening and overnight. Model soundings show saturation into the DGZ but the column keeps the saturation generally below 700mb, so not as much moisture to work with as we had last night. As arctic air continues to advect in from the north-northwest, snow ratios remain around 20:1. Total QPF is only a couple hundreths of an inch with snow amounts around a half to possibly up to 1 inch of dry fluffy snow. The best chance for amounts near an inch look to be across southern IN and along and east of the I-75 corridor. Winter Weather Advisory remains in effect for tonight into tomorrow morning. Strong sfc high pressure over currently over the Dakotas will be dropping south into the central plains overnight. This will keep a tight pressure gradient over the area with a steady wind of 5-15 mph out of the north-northwest. Not only could this blow snow around causing low visibility and even scattered slick spots but it will make for some very cold and bitter wind chills. Low temperatures overnight will fall into the single digits to low teens, when you factor in the wind, the wind chill values will range from 5 below to 5 above zero. Cold Weather Advisory is in effect for tonight into tomorrow morning. Closed upper low will push eastward during the day tomorrow as sfc high pressure over the central plains slowly works eastward. There may be a few lingering flakes or snow showers to the east during the morning but skies will eventually clear out by late morning. Cold air will continue to advect in with highs only in the low 20s. With a northwest wind between 10-20 mph, wind chill values will range from 5 to 10 above zero. && .LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/... Issued at 309 PM EST Wed Feb 19 2025 Thursday night will be another cold one with a 1040mb sfc high over Missouri to keep us clear and calm. Temps will run a couple degrees colder than tonight, but with less wind. Lows in the single digits for most will be a close call for a Cold Weather Advisory, but will hold off on any headlines for now to avoid confusion. Thermal trof finally lifts out, giving way to rising heights and a gradual warming trend in zonal flow. Temps finally crack the freezing mark Friday afternoon, and will recover to above normal Monday into next week. Northern stream trof dives into the Great Lakes after Monday, with a moisture-starved front dropping into the Ohio Valley on Tuesday. Mild and breezy conditions will be the main sensible wx impact. For now will carry slight chance POPs Tue-Wed, but with mild temps the precip should be all rain. && .AVIATION /00Z TAFS THROUGH 06Z FRIDAY/... Issued at 711 PM EST Wed Feb 19 2025 Ceilings are hovering near the MVFR threshold this evening, but should remain prevailing MVFR overnight as a band of deeper moisture streams east across the region. A mid-level vorticity maximum will help force a band of light snow showers west to east across the region tonight. QPF is quite light overall, but brief visibility drops into IFR will be possible over a 2-hr period at any one site. MVFR vis will be possible for slightly longer on either side of the IFR window. Snow diminishes prior to daybreak, with MVFR ceilings lingering through Thu morning east of I-65. NNW of 5-10 kts will gradually turn out of the NW overnight. && .LMK WATCHES/WARNINGS/ADVISORIES... KY...Winter Weather Advisory until 7 AM EST /6 AM CST/ Thursday for KYZ023>043-045>049-053>057-063>067-077-078. Cold Weather Advisory from 1 AM EST /midnight CST/ to 11 AM EST /10 AM CST/ Thursday for KYZ023>043-045>049-053>057- 061>067-070>078-081-082. IN...Winter Weather Advisory until 7 AM EST /6 AM CST/ Thursday for INZ076>079-083-084-089>092. Cold Weather Advisory from 1 AM EST /midnight CST/ to 11 AM EST /10 AM CST/ Thursday for INZ076>079-083-084-089>092. && $$ UPDATE...EBW SHORT TERM...BTN LONG TERM...RAS AVIATION...EBW