-- Discussion containing changed information from previous version are highlighted. --
159
FXUS63 KJKL 190739
AFDJKL

AREA FORECAST DISCUSSION
National Weather Service Jackson KY
339 AM EDT Wed Jun 19 2024

.KEY MESSAGES...

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- Increased cloud cover today from a disturbance to the west will
  yield some subtle relief from the more intense heat this week,
  with highs today in the middle 80s to lower 90s and heat indices
  mostly in the mid 90s with a few locations in the upper 90s.

- Hot weather persists through the remainder of the week and into
  the weekend. Afternoon heat indices may peak around 100 at some
  locations. It will also be dry through Friday.

- The upper level high/ridge bringing our heat wave will weaken
  next weekend and allow a cold front to move into the area,
  possibly bringing thunderstorms Sunday through Tuesday.
-- End Changed Discussion --

&&

.SHORT TERM...
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(Today through Thursday)
Issued at 335 AM EDT WED JUN 19 2024

Upper-level cut-off high pressure centered over the Mid-Atlantic
region reaches peak intensity this afternoon, then weakens and
splits, with the westernmost split retrograding southwest to over
the Bluegrass State Thursday. The eastern split moves to the western
Atlantic northwest of Bermuda. Between the two, an inverted trough
moves toward the Southeast US coastline by Thursday evening.

Dew points continue to trend lower as a drier air mass moves into
the area from the Carolinas, and aided by light downslope
compressional warming. However, the drying trend has not been
continuous, with some areas maintaining lower to mid 70s dew points
still in the pre-dawn hours this morning, particularly in the Upper
Kentucky River Basin.

A warm and dry pattern continues through Thursday with no
precipitation chances. A disturbance roughly aligned with the Lower
and Middle Mississippi River Valley this morning will move northeast
into the Ohio River Valley and Midwest around the upper-level high.
While no precipitation is expected, the cloud cover will provide
significant shading from the sun, especially in the western part of
the forecast area. Thus, forecast highs for today continue a
downward trend, with upper 80s in the southwest and lower 90s in the
central and northeast parts of the CWA. Note that MOS is lower than
the NBM by a few degrees west of Interstate 75, so would not be
surprised if a few locations need to be lowered further, especially
out toward Somerset.

Drier air continues to filter into the region, and will mix down to
the surface this afternoon, which should lower dew points into the
lower to mid 60s across the area. With cloud cover lessening, expect
decent radiational cooling which should support widespread lows in
the 60s, with lower 60s in the typically cooler sheltered valleys.
Fog will be typical in the usual locations within the deeper river
valleys.

Highs rebound back into the lower to mid 90s Thursday afternoon as
the high pressure heat dome moves almost directly overhead, which
should result in mostly sunny to partly cloudy skies. Some models
depict some afternoon cumulus developing on the high terrain along
the Virginia border and moving west into eastern Kentucky later in
the afternoon, but this is not expected to result in precipitation
or lower temperatures.


.LONG TERM...(Thursday through Tuesday)
Issued at 244 PM EDT TUE JUN 18 2024

Persistent upper-level ridging will surface high pressure over much
of the eastern CONUS through much of the long-term forecast period.
Temperatures are expected to continue to be in the 90s with heat
indices approaching 100 degrees. Starting on Thursday, the forecast
597 decameter high will be overhead with easterly flow at the
surface. This dry easterly flow will keep moisture to a minimum on
Thursday which would also keep heat indices relatively lower for
Thursday and Friday. This lack of moisture will more than likely
limit the potential for isolated showers and thunderstorms.

The surface high will gradually begin to shift to the east and as
that occurs, increasing moisture is expected. Also, to the
northwest, a shortwave trough is forecast to dive out of central
Canada into the Great Lakes. This upper-level shortwave and surface
low will increasing surface moisture ahead of a cold front that`s
forecast to dive toward the Commonwealth on Sunday. As for Saturday,
the potential hottest temperatures of the period are expected. Heat
indices are still expected to remain below 100 degrees thus likely
not going to issue head headlines for the weekend but caution should
still be exercised will doing outdoor activities.

The aforementioned cold front is forecast to continue to dive
southeast toward the Commonwealth through the day Sunday. However,
with moisture continuing to be a lacking phenomenon, the overall
strength of the front will be limited. Can`t rule out a few
thunderstorms with FROPA. Models have the boundary slowing down and
stalling out across the CWA which will help to keep enough lift in
place to favor precipitation into Monday. A reinforcing upper-level
wave for Tuesday will bring increased and more widespread showers
and thunderstorm chances for the end of the period. Otherwise, the
area will continue to see high temperatures in the low to mid-90s
with overnight lows in the mid-60s to low-70s and isolated to
scattered thunderstorms each day minus Thursday and Friday.
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&&

.AVIATION...(For the 06Z TAFS through 06Z Wednesday night)
ISSUED AT 124 AM EDT WED JUN 19 2024

Predominately VFR conditions are expected through the TAF period.
Drier air is working into the region due to a more east/southeast
upper flow direction across far eastern, southeastern, and
southwestern parts of the forecast area, but KJKL and other
locations in the Kentucky River and Upper Licking River basins
have yet to experience this drying, with dew points still in the
lower to mid 70s. Within the soupy air mass in the Kentucky River
basin, which includes KJKL, the moisture-rich lower atmosphere is
producing hazy skies with some reductions in visibility noted.
Have therefore includes a reduction in viz to 6SM for much of the
overnight at KJKL. While lower confidence due to advection of
drier air, prevailing MVFR reductions due to morning fog in the
previous TAF package was included as a TEMPO group between
10z and 12z.

&&

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

$$

SHORT TERM...CMC
LONG TERM...VORST
AVIATION...CMC