038
FXUS63 KJKL 202008
AFDJKL

AREA FORECAST DISCUSSION
National Weather Service Jackson KY
408 PM EDT Fri Sep 20 2024

.KEY MESSAGES...

- A potential for showers and thunderstorms returns tonight and
  Saturday and then persists much of the time over the next week.
  The highest probability is around mid week.

- Daily high temperatures will be in the 80 through early next
  week, and should then cool to the 70s.

&&

.UPDATE...
Issued at 105 PM EDT FRI SEP 20 2024

Updated the zones earlier to remove morning fog. As expected
seeing a bit of a Cu field developing under some streaming high
Ci. Forecast is on track. Stayed with original highs, though some
spots in our south have been a little slow to respond to heating.
Did adjust hourly grids to reflect this. Otherwise, no further
changes to the forecast package.

UPDATE Issued at 743 AM EDT FRI SEP 20 2024

Forecast is on track. Morning obs were blended in without
substantive changes.

&&

.SHORT TERM...(Today through Saturday)
Issued at 358 AM EDT FRI SEP 20 2024

Early this morning, upper level high pressure is centered over TX
and is ridging northeast over the lower Great Lakes. A shortwave
trough is over the upper Midwest, along with an associated surface
cold front. The shortwave trough will propagate along the
northeast periphery of the ridge and should be getting picked up
by the back side of a weak upper level trough off the New England
coast by late Saturday. Along its journey, it will support
southeast movement of the aforementioned cold front. The front
will be weakening with time and will probably be ill defined by
late Saturday, but it is expected to be near the Ohio River at
that time. Modest moisture advection on southwest low level flow
ahead of the front could result in elevated instability overnight
tonight into Saturday, and surface based instability on Saturday
afternoon. Although supporting features will be weak, some showers
or thunderstorms won`t be ruled out, and 20-30% POPs will be
used.

.LONG TERM...(Sunday through Friday)
Issued at 408 PM EDT FRI SEP 20 2024

The flow pattern aloft across the CONUS to begin the extended period
will feature a large and broad trough in place over the desert
southwest, with a short wave trough taking shape along the eastern
edge of the larger upper feature. another more vigorous trough is
forecast to move slowly eastward along the norther border of the US
north of the Great Lakes, then make a northward push as it
intensifies. Another area of low pressure is progged to be in place
just off the Mid-Atlantic region. The trough that will be in place
over the west-central Plains early Sunday will move slowly our way
heading into the first of the upcoming work week. A surface front
extending from this feature northward to the southern Canadian
trough will push through the Great Lakes and Ohio Valley regions
Sunday night and Monday, bringing good chances for showers and few
storms to eastern Kentucky. This initial system will move slowly but
steadily through the region, keeping chances for showers and storms
in our area through Tuesday evening.

Once the first system moves off to our east, another trough will be
right on its heels. This second system, according to the latest GFS,
ECMWF, GFS Ensembles, and WPC guidance, will move out of the south
central Plains into the western Great Lakes Tuesday night through
Friday. However, the models area also trying to produce a well
defined tropical cyclone over the Gulf of Mexico, which could move
inland late Friday, and perhaps affect the progression of the second
Plains trough. If this happens, and a TC does form in the Gulf,
we`ll need to watch it closely to see whether or not it moves close
enough to our area after becoming extra-tropical to bring another
round of rain to eastern Kentucky by the end of next week.

The extended looks to start off quite warm, with well above normal
highs in the upper 80s on tap for Sunday, as the initial trough of
low pressure approaches from the west. After that, an invasion of
extensive cloud cover and multiple rounds of rain will act to keep
temperatures quite a bit below normal for the rest of the period,
especially once the first trough moves by and winds shift to the
west and then northwest toward the middle and end of the week.
Daytime highs should top out in the 70s Wednesday, Thursday, and
Friday. Aside from lightning with general thunderstorms through out
the week, there are no weather hazards expected across eastern
Kentucky.

&&

.AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon)
ISSUED AT 155 PM EDT FRI SEP 20 2024

VFR flight conditions expected through the period. Expecting
valley fog again tonight, but impacts at any flight terminals
should be minimal. Winds will be light and variable through
Saturday morning, then increase a bit from the west-southwest to
around 5 kts ahead of a weak cold front that is expected to stall
north of our area, along the Ohio River Valley. Besides being
closer to the surface front, southwest winds at KSYM tend to be a
little stronger due to terrain effects, thus went with a slightly
higher gradient wind there.

&&

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

$$

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