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Area forecast discussion 
National Weather Service Jackson Kentucky
350 PM EDT Fri Oct 21 2016

Short term...(this evening through Saturday night)
issued at 350 PM EDT Friday Oct 21 2016

Lingering isold to sct upslope showers will gradually diminish
through the late afternoon and early evening as surface high
pressure begins to nose its way into the area tonight. In
addition, our low stratocu deck will be slow to dissipate. Areas
most likely to begin clearing first will be our far southwest
counties later tonight or early in the morning. Clearing line
will gradually move eastward through the remainder of the day

Real focus for the short term turns to overnight lows and whether
there will be a potential for any frost. Clouds and a steady
northwest gradient flow around 5 mph will tend to keep our
temperatures up and kill any potential for frost tonight. Feel
the potential for frost will be low Saturday night into Sunday as
well. The center of the sfc high pressure will remain well to our
south Saturday night and gradient return flow will also be on the
increase ahead of an approaching system moving through the
Midwest. Thus radiative cooling will not be ideal. The only
concern might be our typically colder, deeper eastern valleys
where a nocturnal inversion will have an opportunity to set up
before return flow is able to keep the boundary layer mixed out.
As a general rule, western valleys are much easier to mix out
under these circumstances. Guidance does suggest Eastern Valley
locations will see temperatures dropping in the mid to upper 30s
by sunrise Sunday. However, models also indicate that wet bulb
temperatures will remain in the mid to upper 30s. So while fog may
be possible am not confident enough that frost would be a problem.
To summarize, while some very isolated patchy frost in a couple of
spots can not be ruled out, lack of coverage and low confidence
allows leaving any mention of frost out the forecast for now.

Long term...(sunday through friday)
issued at 350 PM EDT Friday Oct 21 2016

A mainly dry and seasonable forecast is in store for eastern
Kentucky through the extended period. The period will start out on
the chilly side Sunday morning with lows in the mid 30s and low 40s.
Temperatures will rebound towards 70 degrees in the afternoon as
high pressure skirts by. A cold front will push through the area
Monday morning but won't bring any precipitation, just a wind shift
back to the north and a much drier airmass. Tuesday morning is
looking quite chilly with co-op MOS showing valley temps at or just
below freezing. So have decided to drop valley temps below
superblend into the low and mid 30s and include patchy frost in the

Temperatures will rebound into the low 70s by Wednesday ahead of
shortwave trough. This trough is expected to bring a cold front
through the region late Wednesday night into Thursday. Moisture with
this frontal passage looks a bit better than in previous model runs
so there is a decent chance for precipitation on Thursday. Low level
moisture appears to hang around on Friday, allowing for at least
partly cloudy skies and seasonable temperatures to prevail.


Aviation...(for the 18z tafs through 18z Saturday afternoon)
issued at 210 PM EDT Friday Oct 21 2016

In general IFR level ceilings have lifted into MVFR territory. Expect
ksym, ksme, and kloz to become VFR by late this afternoon or very
early in the evening. Terminals further east, kjkl and ksjs will
take a few hours longer. However, low VFR stratocu decks are
expected to linger through the overnight with partial clearing
not taking place until Saturday morning into mid-afternoon. Also
seeing some regeneration of some shower activity in upslope flow
as wrap around moisture combines with flow off of the Great
Lakes. While shower activity will be confined to mainly the higher
terrain along the Kentucky/virgina state line, did leave a
mentioned of vcsh for several more hours in most of the tafs.
Gusty northwest winds will gradually diminish through the late
afternoon, becoming light around 6 kts tonight. Then northwest
gradient winds will increase again Saturday to around 10kts.


Jkl watches/warnings/advisories...none.



Short term...ray
long term...jvm

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