952
FXUS63 KJKL 100810
AFDJKL

AREA FORECAST DISCUSSION
National Weather Service Jackson KY
410 AM EDT Mon Jun 10 2024

.KEY MESSAGES...

- Areas of fog are in place for southern parts of eastern Kentucky
  early this morning and locally dense in the valleys.

- Hot weather arrives late this week, with highs in the upper 80s
  to lower 90s taking hold by Sunday.

&&

.SHORT TERM...(Today through Tuesday)
Issued at 410 AM EDT MON JUN 10 2024

07Z sfc analysis shows high pressure nosing into the area from
the west, though cyclonic flow remains for the northeast parts of
the state related to a low over New England and a secondary cold
front north of the Ohio River. This has allowed for temporary
clearing through the JKL CWA which, when combined with the
moisture left behind from the southern rains of Sunday, has led to
the development of fog through the Cumberland River valley -
becoming locally dense in the valleys of the lesser tributaries.
For this reason, an SPS is in effect until 13Z. Otherwise,
temperatures vary from the low to mid 50s in the valleys to the
lower 60s on the ridges. Meanwhile, amid light winds, dewpoints
are generally in the low to mid 50s.

The models, and their individual ensemble suites, continue to be
in pretty good agreement aloft through the short term portion of
the forecast. They all depict the western extent of a deep
Northeast trough at 5h pivoting south into eastern Kentucky today
and tonight. This will bring with it some height falls and an
ample amount of mid level energy - with the most distinct impulse
moving through this evening. The passage of this particular wave
will also mark the 5h trough axis clearing the area allowing for
gradually rising heights and a lessening of the energy in the
weaker northwest flow that remains at mid levels. The model
spread is again quite small so that the NBM was used as the
starting point for the short term grids along with the
incorporation of standard terrain distinctions for temperatures
tonight.

Sensible weather features a mostly dry and pleasant couple of
days - once the fog clears this morning. Cooler temperatures and
lower humidity will be a nice way to start the week - especially
considering the heat to come later in the forecast. We will see a
very small chance for a shower in the northeast parts of the JKL
forecast area this afternoon and early evening on account of a
secondary cold front pushing through the region and lowering
heights/energy aloft - though most places will stay dry or see
just a few sprinkles. The clouds associated with that boundary
clear out tonight setting up a good night for radiational cooling
with many valley spots seeing temperatures as low as the mid 40s
by dawn Tuesday - along with typical river valley fog formation
that becomes locally dense late. Tuesday will be the best day of
the bunch with more in the way of sunshine and temperatures still
on the cool side along with comfortable humidity levels.

The main changes to the NBM starting point consisted of adjusting
the temperatures in order to better represent terrain detail in a
radiational cooling situation. PoPs were low through the period
and only tweaked a notch higher for the northeast with peak
heating this afternoon.

.LONG TERM...(Tuesday through Sunday)
Issued at 247 PM EDT SUN JUN 9 2024

There is good agreement among the ensembles and deterministic
guidance to begin the period. They show surface high pressure
building east into the Ohio Valley and even some shortwave ridging
noted in the mid-levels. This will keep the weather dry and
seasonable through around Wednesday. After this, high pressure
meanders east and mid- and upper level heights will be on the rise
once again leading to dry weather at least through Thursday.
However, warmer air advects into the area, with mean 850mb
temperatures from the EPS/GEFS/GEPS rising to near 18-19 C by late
week. This will give way to afternoon highs in the upper 80s to
lower 90s. However, by Friday there is some disagreement on a cold
front diving into the Ohio Valley in terms of timing and
location. The NBM keeps some slight chance PoPs (generally less
than 15 percent) along and north of I-64 on Friday and right now
will keep this going. Saturday looks dry in most of the ensemble
and deterministic guidance, but again some differences in the
guidance lead to some uncertainty on if this holds. The boundary
might be able to reactivate Sunday, with PWATs rising to 1.2 to
1.3 inches in the ensembles mean of the EPS/GEFS/GEPS. This would
only lead to a around a 20 percent chance of rain mainly south of
the Hal Rogers and Highway 80 region. The cluster analysis shows
most of the area will see generally less than a quarter of an inch
of rain through the period and seems reasonable given the lack of
better moisture return through the period, with PWATs running
around average or just below through the period.

&&

.AVIATION...(For the 06Z TAFS through 06Z Monday night)
ISSUED AT 220 AM EDT MON JUN 10 2024

Clearing overnight and damp grounds, will likely bring MVFR fog
and possibly IFR/LIFR conditions at KSME and KLOZ into dawn and
clearing out between 12 and 14Z. Otherwise, VFR conditions will
prevail today with scattered to broken cumulus at around 5 kft by
mid-afternoon and a potential for a few sprinkles or a stray
shower around. Light winds are expected through this morning,
with west-northwest winds developing in the afternoon peaking at
generally 10 kts or less with max gusts of around 14 to 17 kts.

&&

.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

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