-- Discussion containing changed information from previous version are highlighted. --
531
FXUS63 KJKL 271330
AFDJKL

AREA FORECAST DISCUSSION
National Weather Service Jackson KY
930 AM EDT Thu Jun 27 2024

.KEY MESSAGES...

- Hotter weather is expected to make a comeback on Friday and Saturday,
  with afternoon highs around 90 or in the low 90s and heat index
  values peaking around or in excess of 100F.

- A cold front will likely bring additional rain to the area from
  late Saturday into Sunday. Any storms on Saturday afternoon and
  evening could produce strong wind gusts and heavy rain.

- Another shorter-lived cooldown is anticipated for early next
  week followed by a mid week warm up.

&&

.UPDATE...
-- Changed Discussion --
Issued at 930 AM EDT THU JUN 27 2024

Fog has mostly burned off this morning, with skies clearing
gradually from north to south. The mid-morning update primarily
makes minor tweaks to Sky grids to result in a slightly quicker
clearing trend through this afternoon. Otherwise, observed
temperature trends were incorporated into the grids for a smooth
weather element transition over the next few hours.
-- End Changed Discussion --

&&

.SHORT TERM...(Today through Friday)
Issued at 510 AM EDT THU JUN 27 2024

Early this morning, an upper level ridge was centered over
northern Mexico into the southwestern Conus with ridging extending
into the mid MS Valley and an upper level trough downstream from
the Hudson Bay vicinity into the eastern Conus. An upper level
low is moving across portions of BC and the Pacific Northwest with
an associated trough moving into the western Conus. Meanwhile, a
shortwave trough was moving through the Southern Appalachians
southeastern Conus. At the surface, a frontal zone extended from
the Northeast to the mid Atlantic states into the Southern
Appalachians to the Southern Plains. Nearer to the sagging frontal
zone, a few showers will still occurring near the TN/VA/KY tri
state area while further north behind the front, low clouds or
fog, in some cases dense were observed.

Today and tonight, the shortwave trough over the Southern
Appalachians and into the southeastern Conus should continue to
depart to the south and east with height rises at 500 mb
anticipated across the Commonwealth in its wake. These height
rises will occur as the ridge centered initially over Northern
Mexico and the southwest Conus flattens and builds into portions
of the Southeast including the OH and TN Valleys. At the same
time, a potentially convectively driven shortwave trough should
be in place over the Plains by this evening and near the Mid and
Upper MS Valley tonight downstream of an upper level trough that
moves near the US/Canadian border to Saskatchewan and associated
trough moving across portions of the western Conus. The consensus
of guidance builds the ridge across the southeastern Conus on
Friday, but this ridge may be a dirty ridge so to speak with
eastern KY residing on the northern periphery on Friday.

Lingering moisture over the southern counties combined with the
departing shortwave trough and front to the southeast and a
secondary weak front or sfc trough dropping across eastern KY may
result in showers lingering near some of the VA and TN border
areas this morning and perhaps into early this afternoon. However,
a drier airmass will advect in from the northwest as sfc high
pressure over the Great Lakes builds into the OH Valley. This high
works east into the Northeast to mid Atlantic states tonight and
to the eastern seaboard on Friday. Return flow and the building
ridge over the southeast will lead to a return of warmer and more
moist air once again for Friday. PW that is expected to drop off
into the 0.75 inch to 1 inch range late this afternoon and this
evening as the ridging builds in should increase again later
tonight and in particular on Friday to the 1.5 to 1.8 inch range
or near the 90th percentile. Despite forecast increases in heights
at 500 mb, the increase in moisture and daytime heating should be
sufficient to break the cap across portions of the southern half
of the area as temperatures reach the upper 80s to low 90s and
dewpoints return to the mid 60s to around 70. Coverage should be
limited to isolated to scattered however.

Other than the lingering precipitation chances this morning in
the south, fog will affect several areas this morning and is
expected to be dense in some instances. This fog should dissipate
by no later than the 9 to 10 AM timeframe. A min in precipitation
chances areawide is expected from mid to late this afternoon
through Friday morning. The ridging should support a moderate
ridge valley split tonight with some of the normally colder spots
dropping off to about 59 while coalfield ridges should not fall
below the mid to upper 60s. Along with the ridge/valley split and
following the widespread rainfall on Wednesday and Wednesday
evening, fog should develop in the valleys tonight around or
shortly after midnight and then dissipate within 2 to 3 hours
after sunrise.

.LONG TERM...(Friday night through Wednesday)
Issued at 508 AM EDT THU JUN 27 2024

Isolated showers and storms will be possible Friday night, as a cold
front approaches from the west. The showers and storms will become
widespread on Saturday, especially during the afternoon and evening
hours, as a cold front moves through the region. A few storms on
Saturday could produce strong gusty winds and locally heavy
rainfall. Based on the latest model data, the front will be slow to
exit the area, and may even linger over the region through Sunday,
leading to persistent shower and storms chances for the entire
weekend. Hot and humid conditions will also be in place on Saturday,
as moist southerly flow becomes established ahead of the oncoming
cold front. Temperatures probably won`t be as hot as we`ve seen in
recent days, but with the high humidity in place, highs in the upper
80s and lower 90s will feel like the upper 90s or maybe even a touch
over 100 around eastern Kentucky. Sunday looks to warm but not
nearly as warm as Saturday, as cooler air will slowly trickle into
the area behind the slowly departing cold front.

A major pattern change is in store for Monday, as a highly modified
and much cooler air mass will settle over the region. In fact, highs
on Monday might only make it into the upper 70s and lower 80s, which
will be a nice break from the oppressive temperatures we saw most of
the past two weeks. After starting the weekend with a large trough
of low pressure aloft moving through the eastern CONUS, the upper
level and surface flow pattern will shift to strong ridging across
the eastern half of the nation to begin to new work week. This ridge
looks to be quite strong, and is currently forecast to bring dry
conditions and steadily warming temperatures back to eastern
Kentucky through Tuesday night. After that, another area of low
pressure will dislodge the ridge and push it off to our east by mid-
week. Another cold front will then move through the area Wednesday
night and Thursday, bring yet another shot of showers and storms to
eastern KY. Highs will return to the lower 90s for most locations.

The weather concerns in the extended will be related to the two
rounds of thunderstorms we area expecting over the weekend and
toward the middle of next week. We`ll be on the lookout for strong
wind gusts and locally heavy rainfall that could lead to minor
flooding issues around the area.

&&

.AVIATION...(For the 12Z TAFS through 12Z Friday morning)
ISSUED AT 815 AM EDT THU JUN 27 2024

A wide range of conditions were reported with VFR in some areas,
with some MVFR or IFR reductions most common. Ceiling and or
visibility reductions should begin to improve by 13Z to 14Z,
persisting the longest in portions of the south where a few
showers are possible over the next couple of hours. However,
improvements VFR should occur in all areas before 18Z as high
pressure builds into the area. Winds are expected to be light and
variable through the period. Valley fog with IFR or MVFR
reductions is expected to develop between 04Z and the end of the
period and this could lift into or affect a couple of the TAF
sites, though confidence in this is low at this time.

&&

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

$$

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