010 FXUS63 KLMK 181011 AFDLMK Area Forecast Discussion National Weather Service Louisville KY 611 AM EDT Mon Jul 18 2022 ...Updated Aviation Discussion... .Short Term...(Today and tonight) Issued at 310 AM EDT Mon Jul 18 2022 === Prior to 12z Mon === Remnants of a MCV are producing numerous showers and storms this morning across central KY and southern IN, which has resulted in a few flood advisories, but no major flooding issues thus far. Early morning sfc analysis reveals the frontal boundary is stretching across central IL and IN, with plenty of lifting taking place ahead of the front. Enhanced WAA and 850mb moisture transport has helped increase deep moisture convergence over our region, resulting in high PWATs within a marginally unstable airmass. Storms have become elevated this morning, but lingering 500-1000 MLCAPE has kept thunder going overnight. Storms have also become a bit more progressive in the last few hours, which helps limit any major flooding concerns. Expect these storms to continue an eastward push through the morning hours, though the high PWATs will aid in respectable rain rates. === After 12z Mon === The aforementioned frontal boundary will slowly sag southeastward today, eventually passing through our region by the mid to late afternoon time frame. High PWAT airmass will remain south of the boundary where our best moisture transport and convergence will take place. After this morning's round of showers, showers and storms will redevelop along the boundary by late morning or early afternoon as instability increases. However, hi-res guidance has been consistent on precip being more scattered today. Afternoon temps will only reach the mid 70s in the Bluegrass, and mid 80s just about everywhere else. Increased cloud cover should help limit instability and daytime heating some, but still expect to realize around 1000- 1500 J/kg of MLCAPE. A lack of deep layer shear will inhibit organization of storms, but a few strong storms are still possible. Best chances for afternoon scattered storms will be mainly east of I- 65 of south of I-64, but this is dependent on the location of the frontal boundary. Any delay in the progression of the boundary will result in shift of precip chances to the north and west. Main hazards will be torrential rainfall, gusty winds, and frequent lightning. With FROPA, expect a gradual clearing from the NW to SE later this afternoon and evening. Southern IN counties will be the first to clear out. Scattered showers and storms will gradually move south and east out of the forecast area by this evening as drier post- frontal air moves in. For tonight, temperatures will dip into the upper 60s, and may have some patchy fog develop before Tuesday's sunrise after our recent rounds of rain. .Long Term...(Tuesday through Sunday) Issued at 250 AM EDT Mon Jul 18 2022 By Tuesday morning the lingering upper trof axis will run from the Appalachians down through the Tennessee Valley, and the upper ridge centered over the Four Corners will start to win out. Can't rule out a stray pop-up near Lake Cumberland on Tuesday afternoon, but the vast majority of the area will remain dry. For Wednesday, SW flow will increase as a closed low moving into the Great Lakes pushes a weak front toward the Ohio Valley. With the upper ridge still trying to build overhead, expect oppressive conditions with temps reaching the mid 90s and dewpoints in at least the lower 70s. Resultant heat index values will be in triple digits and could be a close call for a Heat Advisory, mainly west of I-65. Confidence is fairly low as to whether the above mentioned front can generate any precip as it moves through the Ohio Valley Wednesday night. Biggest limiting factor will be mid-level capping, and for now we'll keep precip chances east of I-65, and mainly favoring the evening hours. Depending on when and how far west the cap breaks, a low-end SVR wind threat is not out of the question. NW flow aloft will prevail for the latter part of the week, with gradually warming temperatures as the ridge builds into the mid- Mississippi Valley by the weekend. Look for temps in the mid/upper 90s for most on Saturday and Sunday, with no more than spotty coverage of diurnal pop-up storms. && .Aviation...(12Z TAF Issuance) Issued at 610 AM EDT Mon Jul 18 2022 Most of the overnight heavy rain has now shifted off to the east, though ceilings have lowered in the last few hours. Most obs are bouncing between IFR and MVFR, though HNB has reported ceilings down to LIFR earlier. Overall, expect restricted flight cats through this morning as low ceiling remain overhead. Additional scattered showers and storms are possible this afternoon, which could cause for a brief period of reduced vis. Confidence on timing is limited, so went with periods of VC to highlight potential. Otherwise, we should begin seeing improving conditions by this afternoon and evening as the cold front passes through the region, and we should be VFR at all terminals by tonight. After these rounds of beneficial rain, tonight should be a good night for fog development, which may be dense enough to bring down vis for a few hours towards the end of this period. && .LMK WATCHES/WARNINGS/ADVISORIES... IN...None. KY...None. && $$ Short Term...CJP Long Term...RAS Aviation...CJP