125 FXUS63 KLMK 091440 AFDLMK Area Forecast Discussion National Weather Service Louisville KY 940 AM EST Sun Feb 9 2020 .Forecast Update... Issued at 938 AM EST Sun Feb 9 2020 Current radar shows a line of mostly elevated precipitation moving through western KY from the SW to the NE with one report each of light rain (OWB METAR), light rain/snow and light snow (both mPING reports). Soundings show abundant dry air below 750mb, which is evaporating any falling precip at this time. Probably a nice time to see some VIRGA. P-types will gradually become all rain as as a result of WAA from deep southerly flow. Cloud decks will also lower; have already seen BWG lower from 10kft to 8kft within the past hour as a result of evaporative cooling. In any case, current forecast remains on track with only slight adjustment made to lower PoPs to slight wording throughout the rest of the morning and afternoon. Also refreshed near term grids with current observations from around the area. Updated products are on their way shortly. && .Short Term...(Today and tonight) Issued at 300 AM EST Sun Feb 9 2020 Conditions are chilly this morning under clear skies. A flattening ridge is in place in the upper levels while a 1030 mb sfc high drifts east across the Bluegrass State. Winds are light, and temperatures are running in the low to mid 20s. The clearing won't last long. Mid-level clouds will quickly begin spreading in from the west between now and sunrise. Low pressure over the Plains early this morning will move east to the Midwest today. A southwest LLJ at 850 mb is forecast to increase to 55-60 kts as it spreads NE over Illinois and Indiana. Strong WAA in the 700-850 mb layer evolves northeast near the Ohio River during the midday hours. Brief light showers will be possible as part of an initial warm advection wing of precip generally near and north of the Ohio River. Most areas can expect a dry and breezy afternoon. The southern half of KY will even see sunshine this afternoon as the bulk of the deep moisture is forced northward into Indiana. These areas will have no trouble reaching the mid to upper 50s by late afternoon. Highs in the upper 40s to lower 50s are likely in southern Indiana and northern Kentucky. Wind gusts will reach into the 20-30 mph range. The upstream frontal boundary sinks southeast over the Lower Ohio Valley this evening and overnight. This is also when low level moisture transport and PW values are maximized. Widespread light to moderate rain is expected to break out over southern Indiana this evening. Rain will then gradually spread southeast across central and southern KY tonight into the early morning hours of Monday. Have PoPs eventually increasing to 100 across the board between 00-12z tonight. Rainfall totals through 12z Monday are expected to range from less than a tenth of an inch in the Lake Cumberland region up to 1 inch in southern Indiana. Temperatures overnight will be fairly steady in the 45-50 degree range. Poor lapse rates tonight in the rain should keep wind gusts in check. Sporadic strong wind gusts around 30 mph or perhaps slightly higher are not out of the question, but this will not be common. .Long Term...(Monday through Saturday) Issued at 307 AM EST Sun Feb 9 2020 At the beginning of the Long Term the cold front will stretch from New England to Texas. We'll be under the right entrance region of the upper jet with access to Gulf moisture and precipitable water values slightly over an inch. Widespread rain will be found along the front, with the heaviest amounts across southern Kentucky where 0.5-1.0" will be possible...especially in the Lake Cumberland region. Low pressure moving up the front will slow the boundary's forward progress as it enters the Tennessee Valley, keeping light rain in the forecast for Monday night, especially in southern and eastern Kentucky. We may be able to squeeze in some dry weather on Tuesday, especially in the afternoon and evening, as high pressure moves from the Plains to the Potomac. Wednesday a sharp upper trof will advance form the Intermountain West into the Great Plains with surface low pressure spinning up over southeast Texas and strengthening as it heads northeast into TN/KY by evening. Moisture supply is impressive Wednesday afternoon- evening with water vapor transport pointing from the western Gulf right into Kentucky, along with anomalously high precipitable water values. Right now the heaviest rainfall rates are expected from late afternoon through the evening hours as a low level jet streams north from the central Gulf to the Tennessee Valley and we are positioned under the right entrance region of an upper jet from the Midwest to New England. Rain will be widespread, with the Lake Cumberland region once again receiving the brunt of the rain...possibly an inch Wednesday and another inch Wednesday night. This system is still a few days out and so these numbers will likely change...but it's something that folks in southern Kentucky will want to keep an eye on. Over the past week much of southern and south central Kentucky have received over double their normal rainfall. Streams may have a difficult time handling the additional rain, and downstream from the expected area of heaviest rainfall river flooding may develop on the lower Green and lower Ohio Rivers (downstream from Louisville) during the second half of the week and into the weekend. Rain should taper off late Wednesday night as a dry slot moves in behind the maturing storm system. Can't rule out some flurries Thursday morning. Thursday night through Saturday look dry as robust high pressure slides from the Northern Plains to the East Coast. && .Aviation...(12Z TAF Issuance) Issued at 552 AM EST Sun Feb 9 2020 Mid-level clouds continue to spread in from the west this morning and southeasterly winds are beginning to pick up a bit. This is in response to low pressure developing eastward over the Plains. This system will continue into the Midwest today, and southerly winds will increase across the Ohio Valley today due to a tightening pressure gradient. Gusts around 25 kts will be possible this afternoon. A strong push of warmer air aloft is helping fuel a band of showers moving northeast over Missouri. Southern Indiana and northern Kentucky could see brief rain showers during the late morning and early afternoon hours. Ceilings are forecast to lower this evening, with widespread rain moving through southern Indiana and central Kentucky tonight into Monday. Ceilings and visibilities are likely to continue to deteriorate into Monday morning. Much stronger winds just off the surface will result in LLWS conditions beginning around 00z Monday. Poor low-level lapse rates tonight should result in fewer strong gusts at the sfc, but winds will remain very strong off the surface overnight. && .LMK WATCHES/WARNINGS/ADVISORIES... IN...None. KY...None. && $$ Update...CG Short Term...EBW Long Term...13 Aviation...EBW