272
FXUS63 KJKL 040604
AFDJKL

AREA FORECAST DISCUSSION
National Weather Service Jackson KY
204 AM EDT Tue Jun 4 2024

.KEY MESSAGES...

- After a relative lull in precipitation lasting into Tuesday
  morning, the potential of showers and thunderstorms will
  increase at mid week.

- Somewhat cooler and drier weather will arrive behind a cold
  front which will pass on Thursday.

&&

.UPDATE...
Issued at 1140 PM EDT MON JUN 3 2024

Just a quick update to the forecast mainly to lessen the PoPs in
the near term and take out thunder through the night. Did also add
in the current obs and trends for the T/Td/Sky grids. These tweaks
have been sent to the NDFD and web servers along with a freshening
of the zones, SAFs, and HWO.

UPDATE Issued at 920 PM EDT MON JUN 3 2024

00Z shows weak high pressure just to the east of the state and
this is helping to keep skies mostly clear and most of the
convection outside of our area, along with light winds. Currently,
temperatures are running in the upper 70s to lower 80s most
places but already in the upper 60s and lower 70s for a couple
deeper eastern valleys. Meanwhile, dewpoints have come down a bit
to the low and mid 60s. Have updated the forecast to lower PoPs
through the night and taking out most of the thunder per the
latest CAMs` guidance. Did also add in the current obs and trends
for the T/Td/Sky as well as fine tuning the river valley fog in
the wx grids - expecting a few places to become locally dense
towards dawn. These minor adjustments have been sent to the NDFD
and web servers along with a freshening of the zones, SAFs, and
HWO.

&&

.SHORT TERM...(This evening through Tuesday night)
Issued at 401 PM EDT MON JUN 3 2024

A few showers and thunderstorms are going on across eastern KY and
in neighboring CWAs with daytime heating/mixing. Given the lack of
forcing and shear, don`t expect these to have much impact, just a
quick pulse up and back down again.

These should quickly dissipate in the evening as we lose daytime
heating/mixing. From this point forward, the forecast gets a bit
more complicated. We should stay dry through much of the night
tonight, but clouds will be increasing from the west. Flow will
become more southerly as the upper level ridge and surface high
pressure exit to our east. An upper level shortwave will move into
the region by the afternoon, quickly enhancing pop coverage across
KY and points to our S and W. CAMs show pops starting in our SW and
then progressing eastward into the CWA as we get more into the peak
heating of the day. With the increased Srly flow, temperatures will
modify a bit warmer by tomorrow afternoon, with highs in the mid
80s.

These storms will dissipate again in the evening. However, it
appears as though the next system to impact the CWA will be right on
it`s heels. We will be lucky if we even get a few hour break in some
locations. By 0Z Wednesday, heights will continue decreasing, as an
upper level and surface low move across Southern Canada. From this
surface system, a cold front will descend southward through the
Upper Great Lakes, Mid-Mississippi Valley, and eventually into the
Southern Plains. This front will slowly shift eastward, finally
reaching western KY by 0Z Thursday. Showers and thunderstorms will
have developed along the front and will have raced ahead of it,
especially where the better warm air/moisture/instability is -
beginning to impact eastern KY after midnight Wednesday, and
continuing to increase into Wednesday morning as we transition to
the extended period of the forecast.

Did keep with some valley fog for overnight tonight, along with a
minor ridge/valley temperature difference. Any lingering clouds
could impact the diurnal curve, but incoming clouds in the SW during
the second half of the overnight could also prevent these locations
from seeing temperatures drop quite as low. Didn`t include fog or as
much of a ridge/valley temperature difference for Tuesday night, as
clouds will continue to increase with precip possibly ongoing at
times. Lows both nights should generally be in the 60s, with the
cooler night being tonight (less clouds, light wind, less moisture),
and a few degrees warmer for Tuesday night.

.LONG TERM...(Wednesday through Monday)
Issued at 337 PM EDT MON JUN 3 2024

The extended is still expected to start off quite active, as a
strong weather system moves through the region Wednesday through
Thursday. The pattern aloft remains similar to previous model runs,
with a trough of low pressure still progged to move onshore in
southwestern Canada early Wednesday, with now slightly more
pronounced ridging in place along the west coast of the CONUS.
Further east, a strong trough aloft, with a cold front trailing
southward from it, will be pushing through the Great Lakes and into
New England through the end of the week. The trough will be slow to
move through, as it intensifies and slows down on its eastward trek.
The front trailing from this system will bring widespread showers
and storms to eastern Kentucky Wednesday and Wednesday night as it
moves pushes eastward through the region. The parent trough will
become our primary weather maker the rest of the week, as it moves
slowly through the Great Lakes and into New England. The models
continue to agree that this system will be in place over the eastern
third of the CONUS heading into the weekend. A shortwave trough will
then push southward out of the Great Lakes region on Sunday, on the
backside of the departing original upper trough, and will allow for
scattered showers and storms to finish out the weekend and into next
week. There will be a brief respite from the rain Thursday night
and Friday, as we will be between systems, although a few showers
and storms cannot be ruled out in our eastern counties as we get
brushed by the backside of a large departing trough.

The highest rain chances we see in the extended will be Wednesday
through Thursday, during the passage of a cold front. After that, we
will see several rounds of isolated to scattered showers and storms,
mainly during the afternoon and evening hours, as subsequent troughs
aloft traverse the region. Temperatures should be near normal each
day, with a few day at or slightly above normal, and others at or
slightly below normal. The cooler days will Friday and Saturday,
after the first large trough moves through. There is still a
marginal(5%) chance for excessive rainfall that could lead to
flooding Wednesday through Thursday. The good news is that the
likelihood of heavy rain and flooding is still not increasing as we
approach the middle of the week.

&&

.AVIATION...(For the 06Z TAFS through 06Z Tuesday night)
ISSUED AT 204 AM EDT TUE JUN 4 2024

Valley fog can be seen developing on satellite imagery late
tonight. It will continue to expand overnight, and could affect
many TAF sites at times, but confidence in the extent is low. At
this time have only used a TEMPO group for MVFR conditions. Fog
will dissipate in the morning, leaving VFR conditions everywhere.
Scattered showers and thunderstorms are forecast to develop in the
afternoon, resulting in localized sub-VFR conditions before most
of the activity subsides in the evening. Confidence is too low
for anything more than VCTS to be mentioned in TAFs.

&&

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

$$

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