KLMK issues Area Forecast Discussion (AFD) valid 2019-11-27T09:49:00Z 361 FXUS63 KLMK 270949 AFDLMK Area Forecast Discussion National Weather Service Louisville KY 449 AM EST Wed Nov 27 2019 .Forecast Update... Updated at 445 AM EST Wed Nov 27 2019 A couple of features we're watching this hour. One is a thin band of showers now entering Dubois county. The other is the fairly wide clear slot in clouds behind that line. The showers have been producing some stronger wind gusts from the west southwest...in the 40-45 mph range. Behind that line winds have died back some. Given the Wind Advisory in place now, not planning to issue any special weather statements along this line. Will watch for pockets of stronger wind gusts and issue warning products as needed. The second feature is a bit more concerning. Sunshine later this morning will allow for deeper mixing earlier in the day, while we still have strong winds aloft. Models have been overdoing the winds aloft so far this morning...with NAM and WRFs advertising 70-knots at 850 mb. Area VAD wind profiles have peaked in the 50-55 knot range, closer to the Euro and RAP solutions. As we get some daylight around here, we should mix into the 3-4 kft range in the 10-11 AM EST range. At that point, the Euro weakens winds at 850 mb to 40 knots...whereas the RAP keeps us at 50 knots. Based on upstream obs, would not be surprised to see some wind gusts in the 50-60 mph range along and north of the I-64 corridor from 9 to Noon EST. Our current forecast already is above the high end of guidance for wind gusts. Will nudge those winds up a tad and keep a close watch at those wind profiles to see if we need to upgrade a part of our forecast area to a High Wind Warning. && .Short Term...(Today and tonight) Updated at 300 AM EST Wed Nov 27 2019 990 mb surface low now over eastern Iowa will continue to deepen over the next few hours on its way to southern Wisconsin by daybreak. A couple of bands of showers are expected to develop out ahead of this low's attendant cold front. Will be watching temperature trends ahead of these bands, to see if we could get any surface-based instability, but there is a pretty solid inversion aloft, helping to keep the strongest winds above the surface for now. Satellite does show a nice clear slot that, if current trends continue will move that slot over our area during daylight morning hours. Sunshine should aid in the mixing of the low levels and allow for a very windy morning...with gusts likely in the 40-50 mph range. Expect a field of low clouds to develop within that clear slot thanks to that heating and trapped low-level moisture. Cloudy skies look to stay along and north of the I-64 corridor though, so our southern KY counties could keep gusting a little longer. Current timing of the Wind Advisory product still looks good, so will just re-issue with this forecast package. By this evening, the gradient will continue to loosen as the surface low continues into Ontario. Stratus cloud cover may linger some, as time-height sections keep in a narrow low-level moisture field. The wind mixing and potential for cloud cover will mean temperatures only falling to around freezing, not too far from normal for this time of year. .Long Term...(Thursday through Tuesday) Issued at 315 AM EST Wed Nov 27 2019 Thanksgiving...The long term begins with upper level ridging extending from the Gulf of Mexico northward along the Mississippi Valley sandwiched between two potent low pressure systems, one along the West Coast and the other situated over the NE US. NNE winds flowing around surface high pressure will see a cold start to Thanksgiving with lows hovering right around the freezing mark. Cloud cover will increase throughout the day due to an increase in Gulf moisture transport and weak isentropic lift. Forecast soundings show ample dry air in the mid and low levels that will evaporate any falling precipitation likely resulting in a pretty display of virga during the afternoon. As a result of increased cloudiness and northerly winds, max temps will only reach into the low to mid 40s. Friday through Sunday...After spinning nearly stationary for 48 hours, the West Coast low will eject eastward and begin its advancement across the Rockies, undergoing lee cyclogenesis before entering the Ohio Valley. Rain will make its return by Friday afternoon east of I-65 and become more widespread overnight. Saturday will be a wet one as we sit in the warm sector ahead of the cold front with deep southwesterly flow bringing in copious moisture. A warm day can expected Saturday as max temps reach into the mid 50s across southern Indiana and northern Kentucky gradually increasing to the low 60s across southern Kentucky. Tight gradient will also result in breezy conditions Saturday through Sunday with gusts ranging between 20 and 30 mph. There is also a slight chance of embedded thunderstorms Saturday night, though a stable layer up to 850mb should keep any storms elevated. Actual FROPA should occur sometime Sunday morning. Models indicate a dry period through Sunday late morning into the afternoon hours before wrap around moisture brings rain showers back through the area. Monday and Tuesday...As the upper trough axis passes overhead, a rain/snow mix is possible beginning early Monday morning across southern Indiana and parts of northern and through the afternoon hours for east central Kentucky as a result of continued wrap around moisture from the weekend's exiting system. Monday morning lows will bottom out in the low to mid 30s and ease into the low 40s by afternoon. Tuesday looks to be cool and dry with decreasing clouds as surface high pressure builds in across the area. Morning lows will dip into the upper 20s with afternoon highs reaching into the mid 40s. && .Aviation...(06Z TAF Issuance) Issued at 1215 AM EST Wed Nov 27 2019 Rain shield across the terminals this hour...with a narrow break coming before a couple of other waves of showers are possible before daybreak. Low-level wind shear continues, with south winds at the sites now at the surface, but 45-50 knots at 2 kft. Winds at all levels will continue picking up as the morning goes on. With potential for some clearing by daybreak, 40+ knot gusts are likely at each of the I-64 terminals. A broken deck of clouds then should develop by late morning/early afternoon that could help weaken the wind gusts some. By evening, breezy conditions will continue, but the peak gusts will come down. && .LMK WATCHES/WARNINGS/ADVISORIES... IN...Wind Advisory until 5 PM EST /4 PM CST/ this afternoon for INZ076>079-083-084-089>092. KY...Wind Advisory until 5 PM EST /4 PM CST/ this afternoon for KYZ023>043-045>049-053>057-061>067-070>078-081-082. && $$ Update...RJS Short Term...RJS Long Term...CG Aviation...RJS