993
FXUS63 KJKL 011816 AAC
AFDJKL

AREA FORECAST DISCUSSION...UPDATED
National Weather Service Jackson KY
216 PM EDT Mon Jul 1 2024

.KEY MESSAGES...

- Temperatures 5 to 10 degrees below normal will continue through
  tonight, before temperatures warm to near or slightly above
  normal on Tuesday. Humidity will also increase through midweek.

- The potential for showers and thunderstorms returns by Thursday,
  Independence Day, and lasts through the weekend. The highest
  probability of rain is on Thursday and Friday.

&&

.UPDATE...
Issued at 1055 AM EDT MON JUL 1 2024

Adjustment to sky cover were made for southeastern portions of the
area based on recent satellite trends. The thin low clouds in the
southeast are expected to gradually mix out and dissipate through
early afternoon. Otherwise, additional minor changes were made to
hourly grids based on recent observations.

UPDATE Issued at 649 AM EDT MON JUL 1 2024

Have rerun hourly temps for the day using 6 AM obs as mins.

&&

.SHORT TERM...(Today through Tuesday)
Issued at 350 AM EDT MON JUL 1 2024

Early this morning an upper level trough extends from Quebec
southwestward over the central Appalachians, and a large area of
surface high pressure is centered over Lake Michigan. This is
supplying us with an inflow of cooler and much drier air behind
yesterday`s cold front. There`s still a bit of low level moisture
which has not been scoured away, and this is yielding a few low
clouds and some valley fog in southeast KY.

Once heating kicks in today, mixing will do away with the fog and
low clouds. Even with plenty of sun, the refreshing air mass
shouldn`t allow temperatures much above 80, with most places only
making it to the upper 70s this afternoon. Dew points are expected
to fall to the lower 50s in most of the forecast area by late
today. With mainly clear skies lasting through tonight, that will
set us up for unseasonably cool temperatures for July, with
decoupled valleys settling to lower 50s by sunrise on Tuesday.
Enough low level flow should persist to keep ridges near 60.

The upper level trough will be departing to the east tonight and
Tuesday, and strong ridging will build into the area from the
southwest with rising geopotential heights. At the surface, the
high will slip by to our northeast and our low level flow around
the high will become southerly. The ridging aloft and low level
southerly flow will bring a large warm-up on Tuesday, with
plentiful sunshine pushing us to the upper 80s to near 90.
Although not oppressive yet, dew points will also start to climb.

.LONG TERM...(Tuesday night through Sunday)
Issued at 350 AM EDT MON JUL 1 2024

The flow pattern in the extended will start off with strong ridging
in place across most of the eastern half of the CONUS Tuesday night.
This ridge will extended from southeast Canada in the north,
southward through New England, the Mid-Atlantic region, the Ohio and
Tennessee Valleys, the central and lower Mississippi Valley, all the
way into the southern Plains and the western Gulf of Mexico. A large
scale trough is progged to be carving a path across the Great
Plains, with weak troughing in place across the western CONUS. A
stalled out frontal boundary draped across the deep southeast will
bring persistent rain to the state of Florida. The central trough
will be our first weather maker in the extended, as the eastern
trough weakens and is displaced eastward by the incoming trough. In
the meantime, the ridge will hold its own Tuesday night and
Wednesday, and will keep the weather across the area warm and dry to
start things off. The models were in pretty agreement with the
overall flow pattern.

This pattern will begin to shift Wednesday night, as the trough to
our west finally begins to make inroads to the east. This system
will feature a well developed area of surface low pressure moving
across southern Canada to begin the period, with an occluded front
extending southward from it into the western Great Lakes. This
boundary will link up with a wave of low pressure that will
initially be situated over northeastern Iowa, with the cold front
snaking its way into the central Plains, with other weak waves of
low pressure in place along it. The primary cold front of this
system will move slowly our direction late Wednesday into Thursday,
before making a strong push through the region through out the day,
as the parent low moves across Canada. A secondary wave of low
pressure will take over Thursday night, and will cause the surface
front to become oriented west to east and become nearly stalled out
over the region to end the week and even heading into the upcoming
weekend. We will see multiple rounds of showers and storms across
the area Thursday through Saturday, as waves of low pressure move
eastward along the sluggish boundary. The afternoon and evening
hours will see the highest precipitation chances due to peak heating
and maximized instability. The front should finally being pulling
out of the area Saturday night into Sunday, but may stay just close
enough to eastern Kentucky to allow isolated showers and storms to
persist through the weekend.

Temperatures will be quite warm, with daily readings ranging from
the upper 80s to lower 90s for most locations, leading to muggy
conditions yet again. Nightly lows will quite warm as well, with
readings ranging from the mid 60s to lower 70s on average. No
weather hazards to speak of in the extended at this time, but we
will closer monitor upcoming model runs for the potential for
locally heavy rainfall from thunderstorms Thursday through Saturday.

&&

.AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon)
ISSUED AT 214 PM EDT MON JUL 1 2024

Surface and upper level high pressure will result in VFR prevailing
through the period. The exception will be during the 05Z and 13Z
timeframe, where MVFR and IFR and perhaps locally lower
reductions are possible in valley fog. This valley fog is not
expected to affect the TAF sites however. Winds will be generally
be from the northeast at generally less than 10KT through 23Z,
before becoming 5KT or less for the remainder of the period.

&&

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

$$

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