-- Discussion containing changed information from previous version are highlighted. --
440
FXUS63 KJKL 181844
AFDJKL

AREA FORECAST DISCUSSION
National Weather Service Jackson KY
244 PM EDT Tue Jun 18 2024

.KEY MESSAGES...

- Hot weather persists through the week. Afternoon heat indices
  may peak around 100 at some locations. A few thunderstorms will
  be possible this afternoon, otherwise it will 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 and Monday.

&&

.UPDATE...
Issued at 130 PM EDT TUE JUN 18 2024

Isolated convection is about to start over the area this afternoon
so have updated the forecast to best address that. While most
places stay dry, a few of the storms could become strong with
gusty winds as the main threat. Otherwise, have also updated to
add in the current obs and trends for the T/Td/Sky grids. These
minor adjustments have been sent to the NDFD and web servers along
with a freshening of the HWO.

UPDATE Issued at 1135 AM EDT TUE JUN 18 2024

15Z sfc analysis shows moderately strong high pressure in place
over eastern Kentucky late this morning. A cu field is developing
on track through the area as temperatures warm in this moist air
mass. Currently, readings have soared into the low and mid 80s
most places while dewpoints hover in the lower 70s amid light
southwest breezes. Still can`t rule out a stray shower or storm
later this afternoon despite the high 5h heights in place.
Temperatures are on course to hit the low 90s for highs while
heat indices top out in the 95 to 100 degree range for most. The
forecast has been updated mainly to add in the current obs and
trends for the T/Td/Sky grids along with removal of fog mention
from the text products. These minor adjustments have been sent to
the NDFD and web servers along with a freshening of the zones and
SAFs.

UPDATE Issued at 718 AM EDT TUE JUN 18 2024

The forecast is on track. Just blended in latest observations with
the forecast for continuity purposes.

&&

.SHORT TERM...
-- Changed Discussion --
(Today through Wednesday)
Issued at 317 AM EDT TUE JUN 18 2024

An unseasonably strong upper level low remains positioned over
central Canada. Broader troughing is found west of the Rockies,
while a stout upper level ridge is centered over North Carolina.
At the surface, high pressure is seen across the western Atlantic,
with ridging fanned west across the Eastern Seaboard. A remnant
quasi-stationary boundary is aligned from the Great Lakes through
portions of the Midwest, before transitioning to more of a warm
front through the central Plains. This warm front is tethered to
stronger low pressure for this time of the year across portions of
the Front Range and High Plains region. Partly cloudy to mostly
clear skies are currently in place over eastern Kentucky,
following an afternoon and evening of convection, some of which
was on the stronger-side at times. Current temperatures range
from the upper 60s to lower 70s.

The models remain in excellent agreement through the short term
period, still depicting a strengthening and expanding upper level
ridge that will move north, generally residing from New England
through the Upper Ohio Valley by late Wednesday. At the surface,
high pressure will also expand west with time, allowing for
backing low level flow to the southeast and east, leading to at
least some humidity relief across our area by Wednesday.
The HREF has trended higher with rain probabilities for today over
the past 3 runs; however, given the rising 500 mb heights and
generally lowering PWATs, will only maintain some slight chance
(20%) PoPs across the majority of the area for this afternoon, as
capping may be stronger in reality than currently shown in
forecast soundings. Cloud cover looks to be more prevalent today,
which will keep highs just a bit cooler compared to yesterday,
generally around 90 degrees. Any stray convection that manages to
fire up this afternoon will diminish quickly towards dusk this
evening, with partly cloudy skies overnight and lows ranging from
the mid 60s in the cooler valleys, to around 70 atop the ridges.
Stronger capping will keep a lid on all convection on Wednesday,
with highs back in the lower 90s, although dew points will lower
to the mid to upper 60s, keeping higher heat indices in check.

.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.
-- End Changed Discussion --

&&

.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)
ISSUED AT 145 PM EDT TUE JUN 18 2024

Scattered convection can be expected into the early evening hours
today, though confidence is low as to specific timing and location
of any storms. Given this nature, just going with VCTS for the
northeast sites, at this time. Winds will average less than 5 kts
through the period. The typical valley fog is likely late
tonight - only impacting any TAF sites if/where rain occurs
through this evening.

&&

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

$$

UPDATE...GREIF
SHORT TERM...GEOGERIAN
LONG TERM...VORST
AVIATION...GEOGERIAN/GREIF