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000
FXUS63 KJKL 161127 AAA
AFDJKL

AREA FORECAST DISCUSSION...UPDATED
National Weather Service Jackson KY
727 AM EDT Tue Apr 16 2024

.KEY MESSAGES...

- Chances for showers and a few storms are in the forecast today
  through Wednesday night, and also through next weekend. Chances
  peak Wednesday and Wednesday night when the strongest storms
  are possible.

- Well above normal temperatures will be in place over the area
  through Thursday, with readings peaking in the upper 70s to low
  80s each day, or about 10 degrees above normal. Cooler weather
  follows for the weekend.

&&

.UPDATE...
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Issued at 715 AM EDT TUE APR 16 2024

Just a quick update to the forecast to add in the latest obs and
trends for the T/Td/Sky grids. These small adjustments have been
sent to the NDFD and web servers.
-- End Changed Discussion --

&&

.SHORT TERM...(Today through Wednesday)
Issued at 520 AM EDT TUE APR 16 2024

08Z sfc analysis shows a wavy west to east front has dropped
midway through eastern Kentucky connected back to a developing
area of low pressure over the Central Plains. This boundary
spawned a few storms last evening and even now has a cluster going
to the east of the state. It has also kept skies mostly cloudy and
wind stirred enough to limit much of a ridge to valley temperature
split. Specifically, readings are generally in the mid to upper
60s on the hills while some mid to upper 50s are found in a few
of the sheltered spots. Meanwhile, amid light southerly winds,
dewpoints have come up into the mid and upper 50s across the
board - providing some of the fuel for the earlier storms. Despite
the higher dewpoints, the clouds and light winds have been enough
to keep any fog to a minimum.

The models, and their individual ensemble suites, continue to be
in broad agreement aloft through the short term portion of the
forecast. They all depict the approach of a closed trough low from
the Plains with downstream ridging over Kentucky through most of
the day. The mid level flow transitions to southwesterly this
morning as a lead impulse passes through. Additional impulses
arrive tonight with height falls at 5h commencing as the trough
brushes by to the northwest and then to the north on Wednesday.
The core of the energy with this low does pass on Wednesday
afternoon affecting the northern portion of the JKL CWA. By
evening, the mid level flow will be flattening with a lull in any
weak short waves moving overhead. Given the persistent small
model spread, the NBM was used as the starting point for the grids
along the addition of CAMs guidance for the PoPs through
Wednesday.

Sensible weather features another warm couple of days, though
temperatures will likely be mitigated on Wednesday on account of a
increased clouds and a couple of rounds of convection. For today,
the boundary returns north with rising heights aloft working to
limit convection and even its initialization. The latest CAMs
suggests that some early showers today will hinder the ability of
the area to destabilize for better storm development this
afternoon. Similarly, the approach of the sfc low`s occluded front
tonight would also allow for showers and a stray thunderstorm
around, but with timing that would harm the potential for storms
later Wednesday even as we reach peak heating. For this reason, it
seems, SPC has pulled the slight risk area back to the northwest
of the JKL CWA and closer to the center of the low both at the sfc
and aloft.

The main adjustments to the NBM starting point were generally
related to the consensus CAMs ideas for PoPs and timing today
through Wednesday. Only made some minor adjustments to
temperatures based on terrain tonight on account of the increased
cloud cover and pcpn timing.

.LONG TERM...(Wednesday night through Monday)
Issued at 500 AM EDT TUE APR 16 2024

Active weather still on tap for the extended, as a series of low
pressure troughs move across the CONUS mid-week. The large scale
upper pattern will feature a large trough moving away from northern
New England and southeastern Canada, and out to sea in the north
Atlantic. With the GFS Ensemble seemingly having trouble resolving
all of the expected low pressure systems, decided to use a blend of
the NBM, GFS, and ECMWF model data to fashion a forecast solution
for days 3 through 7. Behind this system, we will see two more
vigorous troughs moving through the Great Lakes and across southern
Canada. The lead trough in this pairing will be our weather maker to
begin the extended. We will see numerous showers and scattered
thunderstorms moving through eastern Kentucky Wednesday night, as a
cold front moves through the region. Once the front has moved by
early Thursday morning, drier air will filter into the area, and
will bring mostly clear skies and continued warm temperatures to
eastern Kentucky. Behind this system, northern stream and southern
stream energy will phase to form a potent shortwave trough over the
central Plains on Thursday. This system will move quite quickly in
our direction, and will bring another shot of showers and storm to
us Thursday afternoon through the day on Friday. A frontal boundary
will extend southward from the southern Canada trough and will link
up with a wave of low pressure that is forecast to form along the
southern reaches of the boundary. This boundary will be the trigger
for showers and thunderstorms across our area to finish out the week.

The previously mentioned surface front is forecast to slow down and
become elongated west to east across our area Friday night through
Saturday, and will continue to fire scattered showers and storms
around eastern Kentucky as it lingers over the area. The front
should finally drift southward Sunday and Sunday night, and finally
be out of the area by Monday afternoon. As the front and its parent
trough move through the area late Friday, winds will shift from
southern to west and then northwest, which will allow much cooler
air to spill into the area for a few days. In face, high
temperatures Friday through Monday should be quite a bit below
normal, with daily maxes topping out in the upper 50s to mid 60s
over the weekend.

Winds will increase and become gusty at times during the passage of
the end of week weather system. Any weather concerns in the extended
will likely occur Wednesday, as the initial weather system and cold
front move through the area. We will be on the look out for strong
storms and locally heavy rainfall Wednesday night.

&&

.AVIATION...
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(For the 12Z TAFS through 12Z Wednesday morning)
ISSUED AT 725 AM EDT TUE APR 16 2024

VFR conditions will prevail through the TAF period. There will be
a small chance for a shower or storm through the area later today
and tonight, but most places stay dry. Winds will be light and
variable this morning before they engage again from the south at
generally less than 10 kts by afternoon. Some LLWS will be
possible late tonight from the south to southwest at 40 kts, as
well.
-- End Changed Discussion --

&&

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

$$

UPDATE...GREIF
SHORT TERM...GREIF
LONG TERM...AR
AVIATION...GREIF