423
FXUS63 KJKL 040900
AFDJKL

AREA FORECAST DISCUSSION
National Weather Service Jackson KY
500 AM EDT Sat Oct 4 2025

.KEY MESSAGES...

- Dry and generally above normal temperatures persist into early
  next week.

- Trough the weekend, valley fog is likely to develop each night.

- Chances for rain return for Tuesday and Wednesday.

&&

.SHORT TERM...(Today through Sunday)
Issued at 445 AM EDT SAT OCT 4 2025

08Z sfc analysis shows eastern Kentucky still protected by high
pressure centered to the east of the state. This high is keeping
the winds light and skies mostly clear again this night - though
some high clouds are slipping across the border from Tennessee.
Despite these, we have seen decent radiational cooling for the
night resulting in a moderate ridge/valley temperature divide
throughout the JKL CWA - while also allowing for dense fog
running along the river valleys. Currently, temperatures vary from
the low 50s in some of the more sheltered low spots to the lower
60s on the hilltops. Meanwhile, dewpoints are running in the low
to mid 50s, most places.

The models, and their individual ensemble suites, continue in
excellent agreement aloft through the short term portion of the
forecast. They all depict 5h ridging parked above eastern
Kentucky through the weekend - though drifting further east and
strengthening with time. This will keep mid level winds light and
any impulse well off from our area, though a notable cluster does
slip past to the west late in the period. In addition, the ridging
will continue to work to suppress any convection through the
weekend. The model spread is once again quite small during the
short term portion of the forecast - still supporting using the
NBM as the starting point of the grids with minimal adjustments
needed - mainly just to beef up the terrain based differences for
temperatures during the night.

Sensible weather features one last warm and dry weekend with
temperatures reaching the low 80s for highs for most of eastern
Kentucky today and Sunday, thanks to plenty of sunshine and the
dry air mass in place. Expect mostly clear conditions again for
tonight with valley fog development - again likely becoming
locally dense towards dawn, Sunday.

The changes to the NBM starting point were primarily focused on
adjusting temperatures tonight for terrain details along with
tweaking the afternoon dewpoints and RH a tad lower today and
Sunday - reflecting the mix down of drier air from aloft.

.LONG TERM...(Sunday night through Friday)
Issued at 500 AM EDT SAT OCT 4 2025

Once again the main changes to the extended forecast this morning
were to enhance the terrain based differences yielding a ridge to
valley split for temperatures Sunday night and late in the new
work week. The PoP chances are looking pretty good by mid week.

The previous long term discussion follows:

Mid-level high aloft will remain just east of the area Sunday
through Monday, but the area will gradually come under the influence
of increasingly southwesterly flow aloft by Monday as a weather
system approaches.

Models differ in their interpretation of this approaching system for
Tuesday into Wednesday, with the ECMWF depicting a less amplified
and more progressive shortwave, while the GFS depicts a more
amplified and slightly less progressive shortwave. Either way,
sufficient moisture will exist for most if not all areas to see
showers and possibly a few thunderstorms, but the ECMWF solution
generally favors a bit lesser rainfall than the GFS solution.
Overall NBM QPF has trended lower, closer to a range of two-tenths
to one-half inch, with this forecast package.

The cold front associated with this passing system crosses the area
Wednesday, lowering temperatures for both highs and lows by about 8
to 10 degrees. However, there are significant discrepancies between
the GEFS, GEPS, and EC ensembles with regards to placement and
strength of shortwaves past Wednesday, making the forecast a little
more uncertain with regards to temperatures for the end of the long-
term period.

&&

.AVIATION...(For the 06Z TAFS through 06Z Saturday night)
ISSUED AT 145 AM EDT SAT OCT 4 2025

Surface high pressure and upper level ridging will keep the TAF
sites VFR through the bulk of the period. Fog has developed again
this in the valleys with localized IFR or worse restrictions
likely. The fog appears increasingly favored to affect SME and SYM
toward morning with a good chance at LOZ as well, warranting
mention in the TAF. JKL and SJS are less likely to experience fog,
so any mention was left out on the 06Z issuance, but a few wisps
of fog cannot be entirely ruled out there either, especially
around sunrise. Winds will remain light generally less than 5
knots at most sites.

&&

.JKL WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

SHORT TERM...GREIF
LONG TERM...CMC/GREIF
AVIATION...GEERTSON/GREIF