795 FXUS63 KLMK 170723 AFDLMK Area Forecast Discussion National Weather Service Louisville KY 323 AM EDT Thu Apr 17 2025 .KEY MESSAGES... * Breezy with unseasonably temperatures Friday. * Shower and thunderstorm chances over weekend. A few stronger storms are possible in southern Indiana Saturday afternoon and evening, and area-wide Sunday afternoon and evening. && .SHORT TERM /THROUGH TONIGHT/... Issued at 323 AM EDT Thu Apr 17 2025 Upper ridging approaches from the west, which is increasing heights over the region. At the surface, high pressure is shifting off to the east and a low pressure system continues to develop over the central Plains. Mid-upper clouds will build in from the west and exit to the northeast later this afternoon. With WAA and increasing heights over the region, expecting to see warmer temperatures in the upper 60s over the northeastern half of the region and the low to mid 70s over the southwestern areas. Along the ridging, vorticity lobes will drift over the region. Any precip associated will likely remain as virga or light sprinkles given very dry conditions below 700mb. As pressure gradients tighten, sustained winds will be breezy between 10-15mph. Tonight, a 45-50kt strong LLJ will move over the region in the overnight hours. However, with thin skis, we should be able to decouple keeping these winds from mixing down to the surface. With continued WAA, low temperatures will likely only cool to the mid- upper 50s. && .LONG TERM /FRIDAY THROUGH WEDNESDAY/... Issued at 323 AM EDT Thu Apr 17 2025 Western trof/eastern ridge pattern amplifies Friday into the first part of the weekend, resulting in at least one or two days of unseasonably warm weather in the Ohio Valley. Deep southerly flow on Friday will push temps to around 80 in the afternoon, and this scenario is usually favorable for a dry air mixdown. Dewpoints will remain in the 50s and a few spots could drop into the 40s especially toward east central Kentucky. Will keep tabs on this for potential fire wx concerns. As the low over the Four Corners closes off Friday night a stout low- level jet will develop from the Red River Valley NE into the Wabash Valley, but given the strength of the southeast CONUS ridge it is likely to remain to our north and west for much of the weekend. Will have an extended period of 60-80% rain chances over southern Indiana, tapering down to a 20% chance near Lake Cumberland through at least midday Sunday. The northward and westward trend from previous runs should keep any SVR or flooding threat solidly into Indiana, where rainfall totals could approach 2 inches as far south as Jasper. However, should remain near or below a half inch across most of central Kentucky. Upper low finally ejects toward the Great Lakes and pushes the main cold front through late Sunday into Sunday night, which is where central Kentucky will get most of its rain. Instability will be the limiting factor in storm severity, but there will be enough shear in play for a few strong thunderstorms capable of producing gusty winds. The flow aloft becomes zonal by Tuesday/Wednesday, leading to a decrease in forecast confidence as we get out into the later periods. Trends do suggest that the main concentration of any severe storms next week should be over the central and southern Plains, with quieter (though not necessarily dry) weather for the Ohio and Tennessee Valleys. && .AVIATION /06Z TAFS THROUGH 12Z FRIDAY/... Issued at 114 AM EDT Thu Apr 17 2025 VFR conditions will continue through this TAF period. The remainder of the overnight will consist of calm to light winds and mostly clear skies. After sunrise, SE winds will pick up around 6-9kts. Mid- level BKN skies will move over the region in the afternoon. Some guidance shows some light rain or sprinkles, however, there is a lot of dry air in the lowest levels, so this should remain as virga. Winds will initially back with sunset, then veer to southerly as a strong LLJ moves over the region and brings LLWS after 4Z through sunrise Friday. && .LMK WATCHES/WARNINGS/ADVISORIES... KY...None. IN...None. && $$ SHORT TERM...SRW LONG TERM...RAS AVIATION...SRW