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fxus63 kjkl 221816 

Area forecast discussion
National Weather Service Jackson Kentucky
216 PM EDT Fri Sep 22 2017

issued at 216 PM EDT Friday Sep 22 2017

Early afternoon update to increase afternoon highs slightly. No
other changes to the forecast package other than a few tweaks to
grids to bring them in line with observations.

Update issued at 1000 am EDT Friday Sep 22 2017

Forecast is on track this morning. Minor adjustments made to the
hourly temperatures and dew points. Will be removing morning
wording and fog from the zones. Otherwise the first day of autumn
Ushers in a stretch of dry and warm weather.

Update issued at 742 am EDT Friday Sep 22 2017

Fog is starting to lift off the valley floor. Have freshened up
the hourly temperatures and dew points through this morning,
otherwise the forecast is on track.


Short term...(today through saturday)
issued at 359 am EDT Friday Sep 22 2017

High pressure remains positioned from New England down to the
Tennessee Valley. Valley fog has set in across eastern Kentucky
under mostly clear skies. Temperatures currently range from the
mid to upper 60s across the area.

A mid-level ridge of high pressure will expand northeast into the
Great Lakes region through the short term. This will keep above
normal temperatures as well as mostly clear skies in place across
eastern Kentucky. Highs today and Saturday will average in the mid
to upper 80s, with lows tonight in the 60 to 65 degree range.

Long term...(saturday night through thursday)
issued at 349 am EDT Friday Sep 22 2017

Surface high pressure will remain in place across eastern
Kentucky through much of the extended in conjunction with a weak
ridge of high pressure aloft. This will promote mostly clear and
calm conditions. Southerly flow in the mid and upper levels to
start out the extended period will also continue the trend of
above normal temps, with highs expected to be in the mid and upper
80s from Sunday through midweek. By Wednesday, winds will become
more northerly as heights begin to lower across the state as a
longwave troughing pattern moves towards the region. While
conditions will remain dry, this may help temps cool a couple
degrees or so compared to previous days.

On Thursday, a surface cold front is expected to approach and
traverse the County Warning Area from the northwest. This will bring an increase in
clouds, cooler temps in the upper 70s for the afternoon, and also
the potential for showers and thunderstorms. Unfortunately models
are not in good agreement with the extent of precip across the
region this far out in the forecast period, with the GFS bringing
a prefrontal band across the County Warning Area Thursday afternoon and evening,
and the ecwmf shows the front dissolving with no precip affecting
the region. Given the uncertainties this far out, stuck with a
blend of the two, which keeps generally slight chance pops across
the County Warning Area to finish out the forecast period.


Aviation...(for the 18z tafs through 18z Saturday afternoon)
issued at 216 PM EDT Friday Sep 22 2017

We are in a stable weather pattern where each day will be similar
to the one before/after. That being said, afternoon cumulus field will
dissipate as sunset approaches. Overnight fog will develop once
again. Overall each night has seen slight improvements in
conditions from the previous, exception being the River Valley
locations. Our more elevated terminals, jkl and loz should
continue to see a gradual improvement from night to night. Sym
seems to be more prone to the effects of local valley fog when it
is dense enough, similar to sjs. Considering the pattern, tended
to stay closer to persistence for ceilings and visibilities. It was nice to
see model guidance close to that line of thinking, adding at least
a little confidence to the effects of overnight fog. Went with
some LIFR visibilities at sym and sjs. Sjs was the only site to pick up
LIFR ceilings. Expect jkl and loz to remain in VFR territory for the
most part. Winds will in general be light and variable through the


Jkl watches/warnings/advisories...none.



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