407 FXUS63 KJKL 011732 AFDJKL AREA FORECAST DISCUSSION National Weather Service Jackson KY 132 PM EDT Sat Jun 1 2024 .KEY MESSAGES... - An upper level disturbance approaching from the west, along with a return of more humid air, will bring showers and possibly thunderstorms back to the area during the weekend. - Weather conditions will become warmer and continue to be unsettled during the week. After a relative lull in precipitation Monday, the potential of showers and thunderstorms will again increase through mid week. && .UPDATE... Issued at 1048 AM EDT SAT JUN 1 2024 Updated the current forecast to reflect slower trends in increasing cloud cover and 1-hr PoPs across the area through this afternoon. The slower arrival of cloud cover and precipitation into our CWA allowed for high temperatures to be raised another couple of degrees primarily in the central part of the CWA where overcast sky cover had been expected to arrive earlier in the day. UPDATE Issued at 751 AM EDT SAT JUN 1 2024 Based on satellite imagery, have increased sky cover a little bit faster today than was earlier forecast. Otherwise, the only changes were to blend early morning obs into the forecast. && .SHORT TERM...(Today through Sunday) Issued at 532 AM EDT FRI JUN 1 2024 Ridging at the surface and aloft is departing to our east early this morning. As this happens, an upper level trough stretching from the mid Mississippi Valley to the FL panhandle is approaching from the west, and low level flow is carrying gulf moisture northward on isentropic lift ahead of the trough. This is resulting in a large area of light rain with embedded heavier showers in that area. The regime will shift eastward with time. Morning sun filtered through high clouds will give way to thickening clouds in our area today, and rain is expected to begin arriving in our western counties this afternoon, and then likely move over the rest of the area during the evening into the late night hours. Forecast soundings initially look stable, and the mention of thunder was restrained during the afternoon and evening. Can't rule out thunder overnight, and a slight chance was allowed in the forecast. The slow moving regime will likely bring more rain on Sunday, but timing of the highest probability during the day is uncertain. Soundings show some instability on Sunday, especially if a bit of heating can occur, and a chance of thunder was included. .LONG TERM...(Sunday night through Friday) Issued at 532 AM EDT SAT JUN 1 2024 General agreement among operational models with the pattern aloft through the extended. Ridging and surface high pressure will yield to a weakening disturbance that will drift from west to east across the region at the start of the extended, or late Monday through Tuesday. Coincident with this time frame, a low will be riding into the northwestern CONUS from the Pacific, through the Northern Rockies and into the Plains. This feature takes on a negative tilt as it tracks eastward along the Northern Tier and into the Upper Great Lakes region. As a result, additional short wave energy will enter into the Lower Ohio Valley by late Tuesday or Tuesday night, and across the Commonwealth on Wednesday. The low sets up residence over the Great Lakes for the remainder of the period, sending additional short wave impulses around the southern periphery of the mean low, into the Ohio Valley. At the surface, eastern Kentucky resides in a warm sector through the bulk of the extended, or until a relatively strong cold front for this time of the year sweeps through the area by the end of the period, probably sometime during the Thursday night to Friday window of time. Sensible weather features a return to an unsettled pattern, with an opportunity of showers and thunderstorms just about every day of the period, with Monday being the least likely day of seeing rainfall. Temperatures will be quite warm through the period, mid to upper 80s for daily high temperatures until the end of the week. Temperatures cool back into the 70s for highs after the aforementioned cold front passes through the area. Overnight lows will run generally in the 60s, but cooling well into the 50s at the end of the forecast as high pressure ushers in drier air and pleasantly cool conditions. No solid signals with respect to hazards through the period. Ensemble probabilistic data suggests nothing in the way of heavy rain, with only a 40-50% chance of rainfall totals GTE to a half inch with the mid week system. Probabilities of an inch or more are around 10% or less. At present, WPC's (forecast) QPF leans towards the upper end of those ranges with general 0.5-1.0 inches of rainfall in the forecast from Tuesday night through Wednesday night. Considering the time of year and that much of the area continues to run at or just a bit below normal on rainfall (southwestern zones being the exception), do not expect this would cause any hydro issues across the area. Thunderstorms will be possible through the period as well, with a noticeable diurnal flavor to the activity. Thunderstorms are most likely Wednesday as MLCAPEs climb to around 1000 J/kg. However, at this time effective shear is marginal at best, around 35 kts or less. Considering that the system coming into the region appears to take on a negatively tilted structure, meaning a more dynamic system, one might expect the environmental conditions to become more favorable for storms with future forecast cycles, thus it will be worth watching. && .AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon) ISSUED AT 132 PM EDT SAT JUN 1 2024 VFR conditions will gradually lower to mainly low-end VFR cigs after 00z this evening in -SHRA, with low-end VFR to MVFR cigs developing late tonight into Saturday morning before most likely returning to at least low-VFR cigs by the end of the TAF period Saturday afternoon. Showers will overspread the forecast area from west to east, beginning between 18z-21z at KSME, and reaching KSJS toward 06z tonight. A few thunderstorms are possible mainly tonight, and primarily west of Interstate 75. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...CMC SHORT TERM...HAL LONG TERM...RAY AVIATION...CMC