Area Forecast Discussion
Issued by NWS Jackson, KY

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FXUS63 KJKL 251418

National Weather Service Jackson KY
1018 AM EDT Sun Sep 25 2016

Issued at 1018 AM EDT SUN SEP 25 2016

Forecast is well on track so far this morning as high pressure
remains in control of the region. Loaded the latest observations
for temps, dew points, and winds into the near term forecast to
make sure they were in line with on going conditions. This
resulted in only minor changes. Also went ahead and reran the ZFP
and HWO to remove morning fog wording, as most observation sites
have shown the fog dissipating over the last 1 to 2 hours. All
changes have been published and sent to NDFD/web.

UPDATE Issued at 715 AM EDT SUN SEP 25 2016

Just a quick update to the grids to fine tune the T and Td grids
per the latest obs and trends. These have been sent to the NDFD
and web servers.


.SHORT TERM...(Today through Monday)
Issued at 400 AM EDT SUN SEP 25 2016

07Z sfc analysis shows a weak front lying across the area with
fairly strong high pressure to the northeast of Kentucky. Despite
the boundary overhead, skies remain mostly clear yet again for
another night. Accordingly, and combined with light to calm
winds, this has been another good night for radiational cooling
resulting in temperatures varying from ridge to valley by 5 to 10
degrees. Specifically, readings range from the lower 60s in the
most sheltered valleys to around 70 on the ridges. Dewpoints,
meanwhile are again running in the low to mid 60s. So far, just a
touch of fog has formed in the lower spots of the Cumberland
Valley with it expected to develop similar to last night along
with locally dense patches near the rivers.

The models are in good agreement aloft through the short term
portion of the forecast as they depict the ridging that has kept
the Wx quite over the region these past few days giving way to
the influence of a robust trough moving east into the Great Lakes
Sunday night and into Monday. This will bring lower heights and
some energy to the Ohio Valley by Monday afternoon. Given the good
model agreement on this feature, in particular, have favored a
model blend solution with still a healthy lean toward persistence
through Sunday night.

Sensible weather will feature another unseasonably warm and mostly
to partly sunny day under the waning influence of the eastern sfc
high. This pattern changes by Monday afternoon as a well defined
cold front moves into Kentucky later in the day. This boundary
will likely bring with it a band of showers and thunderstorms for
eastern Kentucky from Monday afternoon through evening. The
clouds, and later pcpn, associated with the front will probably
keep temps several degrees lower on Monday than today. For
tonight look for another repeat with patchy fog - locally dense -
expected in the valleys toward dawn.

Once again used the CONSShort/ShortBlend as a starting point
into the evening and SuperBlend thereafter through 00z Tuesday.
Did bump up temps a notch today for highs given recent trends with
this pattern. Also, again made more substantial changes to the
terrain derived edit areas and forecast points tonight in the
temperature grids to better reflect ridge and valley differences.
As for PoPs - basically zeroed them out through Monday morning,
before bringing them up by afternoon from west to east with the
arriving cold front. This is in well line with MET and MAV MOS

.LONG TERM...(Monday night through Saturday)
Issued at 245 AM EDT SUN SEP 25 2016

At upper levels, a deep trough and upper low will make a southward
dig from the Northern Plains/Great Lakes into the Ohio Valley
Tuesday into Wednesday. This low may get cut off from the northern
stream flow as it continues to dig further southward into the
Tennessee Valley on Thursday. Model solutions have significant
differences with how it handles the closed low from Thursday onward.
The ECMWF solution has the closed low meandering over our area into
the weekend, whereas the GFS takes the low off the east coast by
Friday. Neither solution seems favorable at this time so have kept
the forecast close to the CR Superblend. If a closed low/troughiness
does in fact stick around longer than the operational GFS solution
indicates, then some showers and cooler temperatures will be
possible during the latter part of the week.

In terms of sensible weather, a cold front will be exiting our
region to the southeast Monday night, with showers and cloud cover
quickly clearing behind it. Much cooler and drier air will
infiltrate East Kentucky behind the front, bringing a welcome
reprieve from the summer heat and humidity. Afternoon highs will top
out in the low 70s through most of the work week before moderating
slightly into the upper 70s by weeks` end. Overnight lows will drop
below normal values (around 55 degrees) for the first time in weeks,
with temperatures mainly in the 40s. A few showers may be possible
during the latter half of the work week, but for now have kept
things mainly dry into the weekend.


.AVIATION...(For the 12Z TAFS through 12Z Monday morning)

High pressure will remain in control of our weather through Monday
morning resulting in VFR conditions for most areas with light and
variable winds. Some diurnal CU is expected to develop across the
forecast area later this afternoon, with bases mainly between 4.5
and 6k ft. These clouds are then expected to dissipate with the
loss of daytime heating this evening. Patchy valley fog will
be around this morning and again form towards dawn Monday,
possibly affecting LOZ and SME with some MVFR BR for a couple of
hours both times.




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