Area Forecast Discussion
Issued by NWS Jackson, KY

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000 FXUS63 KJKL 240735 AFDJKL AREA FORECAST DISCUSSION National Weather Service Jackson KY 335 AM EDT Sat Sep 24 2016 .SHORT TERM...
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(Today through Sunday) Issued at 320 AM EDT SAT SEP 24 2016 06Z sfc analysis shows high pressure still in control of the weather throughout the Ohio Valley and Central Appalachians. This has been a persistent pattern and, as such, conditions are not varying much day to day. For tonight, a few more high clouds may affect our northeast counties through dawn, but skies have been and will remain clear for the vast majority of the area into Saturday morning. With light winds, and high pressure centered to the northeast of the CWA, a good night for radiational cooling is again underway resulting in readings varying by relative elevation and valley slope steepness. Specifically, temperatures range from the mild low 70s on the ridges to lower 60s in the most sheltered locations - slightly up from this time last night. Dewpoints are in the same ball park as last night - generally in the low to mid 60s and fairly uniform throughout eastern Kentucky. Unlike last night, there are some earlier hints of fog developing in the river valleys with EKQ and an ob site near Williamsburg reporting light fog this hour - along with the Harlan airport site. Look for the fog to be a tad more extensive this morning, but still mainly confined to the river valleys - locally dense. The models continue to be in good agreement aloft through the short term. They all depict ridging building into the area from the southwest today and through the rest of the weekend. This takes place north of a mid level weakness and lower heights over the Deep South. It also serves to keep any energy far away from the region - way off to the northeast and northwest. Given the good model agreement have again favored persistence for the main driver of the forecast with minor adjustments toward the latest near term model blends. Sensible weather will feature another unseasonably warm day with humidity a bit higher than yesterday under mostly sunny skies. The limited valley fog will all burn off and dissipate by 10 am today and again a repeat anticipated for Sunday morning. Will allow for a few more clouds this afternoon as the sfc moisture increases and again on Sunday given a boundary off just to the northeast. The night will be dominated by ridge to valley temperature differences under mostly clear skies and light to calm winds. Readings will likely continue their tick up for at least one more night in this stagnant pattern. Again used the CONSShort/ShortBlend as a starting point through the evening and SuperBlend thereafter up to 00z Monday. Did bump up temps a notch today and Sunday for highs given recent trends for this pattern. Also, made more substantial changes to the terrain based edit areas and point based temperatures tonight to better reflect the ridge to valley differences. As for PoPs - basically zeroed them out through Sunday morning, before allowing for some mainly single digit values toward the end of the short term forecast period - in line with all MOS guidance. .LONG TERM...(Sunday night through Friday) Issued at 335 AM EDT SAT SEP 24 2016 Models have come into much better agreement with the transition from summer-like to seasonal fall weather during the first half of the coming work week. This occurs as a deep upper level trough, currently over Wyoming, splits with its northern piece shifting eastward and breaking down the upper ridge currently in place over the Tennessee Valley. The trough and closed low system will dig southward from the Great Lakes into our area Tuesday and Wednesday, then may push off the east coast. There are some discrepancies with how the models handle the closed low beyond the Wednesday time frame and this could have impacts on how long the cool air sticks around as well as potential cloud cover. However, there is still good agreement with the initial transition to cool weather. At the surface, all models have trended toward the faster and drier frontal passage solution shown in the past several ECMWF runs. In terms of sensible weather, summer-like warmth comes to a close Monday as a cold front approaches the region. Pops increase Monday afternoon and continue through Monday evening as the front quickly passes through East Kentucky during the evening time frame. Less than a quarter inch of rain is generally expected with the frontal passage, which won`t make much of a dent in the rain deficit for the month of September. Some lingering showers may be possible along the Virginia border Tuesday morning but otherwise the area should be dry by dawn on Tuesday. A much cooler and drier air mass will invade the region behind the front, with afternoon highs topping out in the low and mid 70s for the remainder of the work week. Overnight lows will dip below seasonable values with temperatures ranging from the mid 40s to low 50s.
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&& .AVIATION...(For the 06Z TAFS through 06Z Saturday night) ISSUED AT 130 AM EDT SAT SEP 24 2016 High pressure will remain in control of our weather through the weekend resulting in VFR conditions for most areas with light and variable winds. Patchy valley fog is again expected to develop later tonight but should stay confined to the deeper river valleys, with the exception of some MVFR BR at SME for a couple of hours around dawn this morning, otherwise have kept the TAFs to one line. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...GREIF LONG TERM...JVM/ABE AVIATION...GREIF is the U.S. government's official web portal to all federal, state and local government web resources and services.