Area Forecast Discussion
Issued by NWS Jackson, KY

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000 FXUS63 KJKL 181900 AFDJKL AREA FORECAST DISCUSSION National Weather Service Jackson KY 200 PM EST Thu Jan 18 2018 .UPDATE...
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Issued at 200 PM EST THU JAN 18 2018 Issued an update to input the latest observations and adjust them into the afternoon. Temps seem to be a degree behind on trends so lowered the high temp by a degree. The rest of the forecast is on track. UPDATE Issued at 920 AM EST THU JAN 18 2018 Updated the forecast to input the latest observations and trend them into the morning hours across the area. Most temperatures have now warmed above zero by now. Some of the more sheltered eastern valleys are still hanging around zero. A new zfp was not needed for this update. UPDATE Issued at 735 AM EST THU JAN 18 2018 Hourly sky cover and hourly temperature grids have been updated based on observation and satellite trends. No other changes were needed at this time. Despite the cold start, temperatures will begin to moderate to start today.
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&& .SHORT TERM...(Today through Friday) Issued at 305 AM EST THU JAN 18 2018 The axis of an upper level trough extending from Quebec to the Southeast Conus continues to move east of the area with surface and upper level ridging building into the region. Stratocu and flurries linger near the VA border and in the vicinity of Lake Cumberland where a westerly fetch across the lake appears to have lead to clouds forming east of the Lake likely from steam over the lake. Temperatures vary generally in the single digits through some valley locations that have remained clear are in the single digits below zero. Surface high pressure over the Southeast Conus and centered over the Lower MS Valley will build into the region today with mid level heights rises through at least the middle part of the day before remaining generally steady as a shortwave trough works into the Great Lakes region. Warm advection will begin aloft today, with 850 mb temperatures initially about 3 to 8 below warming to around 0C by this evening. However, despite this warm advection and abundant sunshine the snowpack currently in the about 1 to 4 inch range will likely suppress temperatures to below MOS guidance numbers. The superblend guidance of low to mid 30s appeared reasonable and did not stray far though given the cold start it is possible temperatures even fall short of these numbers. The snowcover should factor into the picture again tonight with high pressure and light winds. For this cycle, undercutting the superblend guidance numbers for valley locations was continued, trending toward the colder coop mos numbers. Further height rises will continue through the end of the period with further warm advection with sfc high pressure still in control. 850 mb temperatures should warm to around 3C by the end of the period. Temperatures should moderate further into the low to mid 40s for most locations or near climatological normals. .LONG TERM...(Friday night through Wednesday) Issued at 240 AM EST THU JAN 18 2018 Zonal flow will set up in the mid levels as we head into the upcoming weekend, with a nice warm up anticipated. We will could see cold conditions Friday night with snow lingering on the ground with a decent chance to go lower than guidance. This could put our valley locations into the teens Friday night. As southerly flow takes hold Saturday, temperatures will get a boost into the 40s. Isentropic ascent will develop as we head into Saturday night and Sunday and could yield some drizzle across the northwestern third of the forecast area, mainly impacting our bluegrass counties and perhaps areas north of I-64. With the low level flow not really downsloping across our area, we could see a little more coverage in the drizzle. Regardless, probably not a whole lot of sunshine come Sunday. By Sunday night, shortwave ridging will develop as a strong cold front pushes across the central plains. This front will be associated with a strong area of low pressure tracking across the great lakes early next week. As this happens, this cold front will track across the area, providing a period of showers. Still some slight differences in timing on the models, but looks like Monday afternoon and Monday evening is when rain chances will peak. Conditions dry out through the rest of the forecast period as high pressure builds back into the region. While it will turn cooler behind the front Monday night into Tuesday, it looks like temperatures should remain more around seasonable values for mid to late January. with highs in the 40s and lows in the 20s. && .AVIATION...(For the 18Z TAFS through 18Z Friday afternoon) ISSUED AT 1143 AM EST THU JAN 18 2018 High pressure has settled through the area with clear skies expected through the TAF period. Thus VFR conditions are expected throughout the TAF period. Wind will generally by from the southwest today from 5 to 10 knots before becoming light and variable after 00Z. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...SHALLENBERGER SHORT TERM...JP LONG TERM...KAS AVIATION...SHALLENBERGER is the U.S. government's official web portal to all federal, state and local government web resources and services.