361 FXUS63 KJKL 161216 AAB AFDJKL AREA FORECAST DISCUSSION...UPDATED National Weather Service Jackson KY 816 AM EDT Sun Oct 16 2022 .UPDATE... Issued at 758 AM EDT SUN OCT 16 2022 Minor adjustments were made to sky cover as well as hourly temperatures and dewpoints based on recent observations and satellite trends. No other changes were needed at this time. && .SHORT TERM...(Today through Monday) Issued at 335 AM EDT SUN OCT 16 2022 07Z sfc analysis shows a frontal boundary laying southwest to northeast across Kentucky. This will eventually serve as a lifting mechanism and glide path for higher moisture and convection to move into our area later today. Currently there is a decent gradient in temperatures across it - running from the lower 40s in the northwest to the mid 50s on the ridges in the southeast. Meanwhile, some of the eastern valleys are in the mid 40s. Dewpoints likewise vary from the upper 30s northwest to near 50 degrees in the southeast. Winds currently are similar on either side of the front - generally light and variable. Skies are variably cloudy through the area around this boundary, as well, though, despite the clear patches and light winds, fog has been quite limited early this morning. Additionally, lower and thicker clouds are inbound from the southwest ahead of an approaching cold front to the northwest. Already showers are moving through south west and central Kentucky - more substantial in central Tennessee - well ahead of the main front's arrival. The models are in good agreement aloft through the short term portion of the forecast. They all depict the large and dominant deep negative anomaly of a trough extending from the Hudson Bay south into the Tennessee Valley. The core of this trough will plunge through the Great Lakes and into the Ohio Valley later tonight into Monday. Height falls work deep into Kentucky during this process with a band of stronger mid level energy descending into our area by Monday evening - marking a doubling down on the cold weather pattern that has been over the region basically since fall began. Given the small model spread have favored the blended NBM for the starting point of the grids with little in the way of adjustments needed. Sensible weather will feature a still mild day, today, but one with increasing clouds and convection developing as moisture builds over eastern Kentucky along the existing boundary and ahead of the main upper support, that turns it into a cold front, later tonight. The front and some instability will likely be enough for a few thunderstorms this afternoon across the area. In fact, a couple strong storms cannot be ruled out due to a favorable wind pattern aloft and climbing sfc dewpoints - though weak mid level lapse rates will be a limiting factor. The HRRR and NAMNest do show some organization possible for the convection this afternoon with even a hint of updraft helicity as a few of the cells exit to the east by evening. All in all, the coverage and substance of the convection has trended upwards the past forecast cycles so am inclined to go along with this idea. After the cold front moves south of the JKL CWA tonight the showers will end but CAA in its wake make for uniformed temperatures decreasing from northwest to southeast through the night. This leads to a significantly cooler day on Monday along with brisk west to northwest winds as temperatures do not climb too far into the low and mid 50s for highs. The main adjustments to the NBM starting point were to tweak some of the spot max and min temperatures through the period. Additionally, the CAMs consensus guidance was incorporated into the PoPs to help with timing and placement of the higher threat for more substantive convection later today into the evening. .LONG TERM...(Monday night through Saturday) Issued at 500 AM EDT SUN OCT 16 2022 The period will begin with a very large, stacked low pressure system centered near the Great Lakes, and wind flow around it pulling a very chilly air mass southeast into KY. This system will be at the heart of a deep upper level trough over the eastern part of the continent. Precip rotating around the low should remain to our north, but some clouds could make it to our northeast counties. Sub freezing low temperatures look to be on the way for Monday night, with a repeat for most places on both Tuesday and Wednesday nights. Cloud cover could hinder the drop in temperatures for our northeast counties on Monday night, and a tight pressure gradient may also be problematic for decoupling. Even so, it looks like it will just be a question of how far below freezing we go. A Freeze Watch was issued for Monday night into Tuesday morning in collaboration with all surrounding offices. The low pressure system at all levels is expected to drift north to Hudson Bay late in the week. Our flow aloft will become more zonal. Meanwhile, surface high pressure will drop south from the Manitoba/Ontario border Monday night to the lower Mississippi Valley Wednesday, and then head to the East Coast for the weekend. It will keep us cut off from any meaningful low level moisture return, but it will eventually allow for warm air advection to return. Aloft, models still don't agree on the evolution by next weekend. However, any features look weak and moisture starved, and a dry forecast has been maintained. && .AVIATION...(For the 12Z TAFS through 12Z Monday morning) ISSUED AT 815 AM EDT SUN OCT 16 2022 Mid and high clouds will continue to increase to begin the period ahead of an approaching cold front. This front will work across the area this afternoon and evening, finally departing into VA overnight. Chances for showers are best generally south of the Mtn Parkway where higher boundary layer moisture and limited instability will be enough for isolated thunder between 17Z and 03Z. Mainly VFR conditions are expected through the period, though some MVFR will be possible near and just behind the front for locations south of the TAF sites. Winds, initially light and variable, will become predominately southwest at 5 to 10KT around 15Z with some gusts up to 15KT possible outside of any thunderstorms. Stronger gusts are anticipated with any thunderstorms. Winds will become northwest to west behind the front between 1Z and 7Z. && .JKL WATCHES/WARNINGS/ADVISORIES... Freeze Watch from Monday evening through Tuesday morning for KYZ044-050>052-058>060-068-069-079-080-083>088-104-106>120. && $$ UPDATE...JP SHORT TERM...GREIF LONG TERM...HAL AVIATION...JP