513
FXUS63 KJKL 090255
AFDJKL

AREA FORECAST DISCUSSION
National Weather Service Jackson KY
1055 PM EDT Sat Jun 8 2024

.KEY MESSAGES...

- As moisture increases, there is a small chance for showers into
  this evening.

- The next passing cold front will bring increasing rain chances
  to eastern Kentucky later tonight into Sunday.

- Cooler air will be reinforced across the region early next
  week, before temperatures modify back to above normal by the end
  of the period.

&&

.UPDATE...
Issued at 1055 PM EDT SAT JUN 8 2024

The forecast is on track so no significant changes are needed with
the late evening update. Did blend in the latest hourly
observations into the grids with the forecast.


UPDATE Issued at 726 PM EDT SAT JUN 8 2024

There are no changes to the forecast. Radar shows precipitation
falling out of mid-level clouds but no stations are measuring
precipitation. Will keep low-end PoPs in the forecast to account
for the possibility of sprinkles or light showers through the
evening. With no changes to the forecast, will forego issuing a
new zone forecast product until the late evening period.

&&

.SHORT TERM...(This evening through Sunday night)
Issued at 435 PM EDT SAT JUN 8 2024

Late this afternoon, an enlongated upper level trough extended
from the vicinity of Maine across Quebec to Ontario. One upper
level low was moving within this general area of troughing and
centered in the Maine vicinity with another upper level low
centered in Ontario northeast of Lake Superior. To the south an
upper level ridge was centered over the Lower MS Valley vicinity
and extended west into the Southern Plains and across portions of
the Southeast. One disturbance in the west to northwest flow aloft
from the Plains and Central Conus into the eastern Conus and OH
Valley region was moving across the Commonwealth at this time with
some light showers and sprinkles associated with it. Meanwhile,
another shortwave extended from the upper level low into the
western Great Lakes/Upper MS Valley vicinity south toward the mid
MS Valley area. At the sfc, high pressure was centered across the
southeastern Conus/Southern Appalachian region while a sfc low
was moving across the Lower MI Area with the associated frontal
zone southwest to near the KS/OK border and then northwest near
the front range area of WY and CO.

Tonight and Sunday, the initial shortwave will pass east though
the evening while the upper low in Ontario moves toward Quebec and
sends a couple of shortwave troughs across the Great Lakes and
into parts of the Northeast to OH Valley. At the same time, the
sfc low currently in the MI vicinity should track to the Northeast
U.S coast and the off the eastern seaboard while the the trailing
front sags into the OH Valley to Southern Plains. This boundary
should continue sagging south across eastern KY on Monday and then
south of the area on Sunday night. High pressure should nose into
eastern KY for Sunday night while a secondary front to the north
becomes diffuse near the OH Valley in advance of stronger high
pressure building into the Upper MS Valley.

Isolated to perhaps scattered showers are possible through early
this evening, though this may not amount to more than sprinkles as
upstream there have been no measurable rainfall reports over
central KY. A lull in between systems is expected overnight though
clouds should continue to stream into the area on west to
northwest flow as the next couple of shortwaves approach along
with the cold front. Convection upstream may track into portions
of the OH and TN Valley overnight or additional development may
occur as moisture is gradually advected toward eastern KY. A
gradient in PW is anticipated near or west of I 75 into south
central KY/the Lake Cumberland region late tonight and would be
the most favored area for convection late tonight. Additional
convection is anticipated on Sunday ahead of the front and as the
shortwaves cross the Commonwealth. The deepest moisture will be
in the south, generally from the Hal Rogers Parkway/KY 80 corridor
south. This area will have the best chance for showers and some
storms on Sunday though PW from about the Mountain Parkway south
should be at least 1 inch or more into early afternoon and
activity north to the area should be more scattered in nature and
then more isolated further north.

The cloud cover should keep temperatures more uniform compared to
the past couple of nights tonight, though clearing on Sunday night
may allow for a modest ridge/valley temperature split as drier air
begins to arrive. Some valley fog is not out of the question
tonight, especially where any convection occurs. Following
additional anticipated convection on Sunday, more in the way of
valley fog should occur over the deeper southern and eastern
valleys.

.LONG TERM...(Monday through Saturday)
Issued at 320 PM EDT SAT JUN 8 2024

At the surface, the period starts off with high pressure nosing east
and cold front pushing toward the Gulf Coast. The mid-levels we will
see a trough extending from the Northeast into the Ohio Valley.
These features will continue to usher in a drier and slightly below
below normal temperatures for Monday. This as ensemble mean of PWAT
values from the EPS/GEFS/GEPS show us staying below 1 inch. The dry
weather and near normal temperatures hold on through mid-week with
surface high pressure remaining in place across the Ohio Valley.

After this, there is good agreement in the ensembles and
deterministic on the surface high pressure pushing east some and
we see some moisture return albeit on the lower end, with around 1
inch PWATs. We will keep the the mainly around a 15-20 percent
PoPs in the afternoon on Thursday mainly in the Cumberland Valley
and higher terrain given some uncertainty on the mid- and upper
level pattern noted in some of the ensembles and deterministic
guidance. Then there is decent agreement on a cold front dropping
across the Ohio Valley by the end of the week into the weekend.
Even so, there is disagreement on the timing and location of this
boundary and therefore leads to uncertainty on when PoP chances
will be highest and even how high to go with PoPs. For now, stuck
close to the NBM, which keeps PoPs Friday and Saturday generally
in the 20 percent range or less. This seems reasonable given the
front looks weaker, with little change in moisture. Overall not
expecting much in the way of rainfall through the period, with
combined ensemble guidance mean of the EPS/GEFS/GEPS showing
probability of less than a quarter of an inch through the period
being around 60-70 percent.

&&

.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
ISSUED AT 733 PM EDT SAT JUN 8 2024

Extensive cloudiness will continue into the overnight, with more
extensive lower cigs working in with shower and possibly
thunderstorm activity toward morning, especially after sunrise.
KLOZ and KSME stand the best chance of being impacted by this
activity, with lesser chances at the other TAF sites. VFR
conditions should prevail through at least 12z, with best chances
for MVFR cigs/conditions between 12z and 19z, when there is also
the slight chance for a thunderstorm. Light and generally variable
winds are expected through the period becoming west and then
northwest at generally less than 10 kts Saturday afternoon after
~16z. There is also some variability in the guidance with the
possibility of LLWS from the southwest between 06Z and 12Z at up
to 40 kts, with NBM guidance having it and CONShort leaving it
out. At this point opted to leave LLWS out late tonight.

&&

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

$$

UPDATE...CMC
SHORT TERM...JP
LONG TERM...DJ
AVIATION...CMC