724 FXUS63 KLMK 221027 AFDLMK Area Forecast Discussion National Weather Service Louisville KY 627 AM EDT Wed Oct 22 2025 ...Updated Aviation Discussion... .KEY MESSAGES... * Dry and cool weather is expected through the end of the week. * Breezy westerly winds are expected this afternoon with gusts of 20-30 mph. * Frost Advisory mainly for valley locations Thursday morning across southern Indiana and portions of north central Kentucky. More widespread frost, and perhaps a light freeze for some, on Friday morning. * Rain chances begin to increase late this weekend into early next week, though forecast confidence is lower at that time range. && .SHORT TERM /THROUGH TONIGHT/... Issued at 321 AM EDT Wed Oct 22 2025 Quiet night ongoing across the area with steady WSW to W winds keeping temps from falling out too much so far. That being said, can get an impressive ridge/valley split in this setup. Case in point, the KY Mesonet site in Cumberland county is currently sitting at 32F with most everyone else in the 40-50F range. Decoupled valleys are going to be the theme through the short term as they also played a role in the Frost Advisory headline for later tonight (Thursday AM). Temps are expected to start out chilly this morning, mostly in the low and mid 40s. A steady wind could add just a bit more nip to the air. Another fairly gusty day as west winds pick up between 10 and 20 mph, occasionally gusty between 25 and 30 mph late morning through the afternoon. Despite plenty of sun, temps struggle in the upper 50s and low 60s for most this afternoon. Southern KY still likely makes it to the mid 60s. Tonight winds will slacken, although we keep a light wind around 3 to 8 mph for most locations. Valleys will decouple, but most other common terrain areas will likely stay just a bit mixed. As a result, makes for a pretty tricky challenge for any Frost Advisory headlines. Expect to see at least areas of frost for decoupled valleys, but the steady winds will likely limit frost production to patchy elsewhere. Decided to issue a mainly valley based headline for Thursday AM in coordination with other offices to cover the concern. Left the Louisville area out given the overall milder nature of the larger urban sprawl. Still have much more confidence for widespread frost for most of the area for Friday morning, but will hold off on that headline decision in coordination with our neighbors for now. A light freeze isn't out of the question for some areas early Friday. See long term for more info. && .LONG TERM /THURSDAY THROUGH TUESDAY/... Issued at 321 AM EDT Wed Oct 22 2025 Thursday - Saturday Night... Expansive troughing over the upper Midwest, Great Lakes region, and New England will be in place late week. Our area will be situated in the NW flow aloft between that feature and upstream ridging. Meanwhile, cold Canadian high pressure builds in at the surface, settling over our near our area on Friday. By Saturday, the trough will push off to the east, with upper ridging briefly taking hold from the SE CONUS up through the mid Mississippi River Valley. The end result from this pattern through the first part of the weekend will be continued dry conditions, with the main focus on cool temperatures, particularly overnight lows. After a chilly start, we'll see steady WNW winds on Thursday in the presence of plenty of sunshine. Nevertheless, only looking at highs in the low and mid 60s for most as H85 temps will only be in the 1 to 4 C range. The coldest night of this forecast period continues to look like Thursday night / Friday AM as the surface high settles near or over the area, and good radiational cooling allows temps to crash. Looking like some of our cooler valleys may end up a degree or two on either side of 30, while most other areas should see low and mid 30s for min Ts. Will continue to mention widespread frost potential for much of the CWA, with some focus for a light freeze, especially over in the Bluegrass region. Time heights do show some potential for high clouds moving in after 06/09z, so this could hurt confidence a bit. Have considered and discussed a Freeze Watch (50% confidence in 30F or less for a couple hours) with surrounding offices, but everyone has decided to hold off for now. Frost Advisory headlines seem much more likely at this point, but not convinced just how widespread any freeze areas will be. Sunday - Tuesday... By late weekend, the upper ridge axis over our area will give way to a slow moving shortwave ejecting out of either the Red River Valley or the mid Mississippi River Valley. Confidence lowers by this time as the upper pattern gets pretty messy into the early part of next week. It is possible we still stay dry on Sunday also, depending the placement of that aforementioned shortwave. Temps will also be depending on that, but in general, they look to be a bit milder and near normal in the mid to upper 60s for most. We'll continue to carry a chance for showers on Sunday, but the bigger focus will be on the Monday into Tuesday time frame as an anomalous shortwave trough is likely to dig into the central CONUS, and could potentially bring some impactful weather to our region. For now, every run of every model is different with timing/placement/strength of this feature, so will not have any real confidence in details. That being said, there is decent confidence in shower and storm chances through this time, especially by Tuesday. && .AVIATION /12Z TAFS THROUGH 18Z THURSDAY/... Issued at 627 AM EDT Wed Oct 22 2025 VFR conditions are expected through this TAF cycle. Look for light WSW to W winds early this morning, before stronger W winds take hold by mid to late morning. Look for sustained winds between 10 and 20 mph with gusts once again in the 20 to 30 mph range through the afternoon. Winds slacken by early evening, with light WSW taking over once again. Very few clouds expected through this cycle. && .LMK WATCHES/WARNINGS/ADVISORIES... KY...Frost Advisory from 4 AM to 9 AM EDT Thursday for KYZ025- 031>037-039>043-047>049-056-057. IN...Frost Advisory from 4 AM EDT /3 AM CDT/ to 9 AM EDT /8 AM CDT/ Thursday for INZ076>079-083-084-089>092. && $$ SHORT TERM...BJS LONG TERM...BJS AVIATION...BJS