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000
FXUS63 KJKL 220235 AAA
AFDJKL

AREA FORECAST DISCUSSION...UPDATED
National Weather Service Jackson KY
1035 PM EDT Sat Apr 21 2018

.UPDATE...
Issued at 1035 PM EDT SAT APR 21 2018

The forecast was in good shape. Updated the zone forecast text
product to remove outdated evening wording. Also tweaked the
hourly weather grids using the latest obs to establish new trends.

UPDATE Issued at 747 PM EDT SAT APR 21 2018

The forecast is on track so far this evening. The latest obs were
ingested into the hourly forecast grids to establish new trends.
Other than that, no other changes were necessary.

&&

.SHORT TERM...(This evening through Sunday night)
Issued at 340 PM EDT SAT APR 21 2018

The afternoon surface analysis shows an area of high pressure
posted up across the Great Lakes and the upper level ridge remains
in place from the Gulf Coast to the Upper midwest. This leading
to mostly sunny skies and dry conditions across eastern Kentucky.
Matter of fact many areas of seeing afternoon relative humidity
values in the upper teens this afternoon, but the winds have
remained light leading to less of the fire weather concern
overall. Ahead of the approaching upper level system we will see
increasing high clouds through the night, but given the low
dewpoints some of the eastern valleys could see a touch of patchy
frost tonight. Given the clouds and patchy nature headlines will
not be hoisted at this time.

All eyes turn to the upper level low that will deepen as it moves
southeast into the Lower Mississippi River Valley Sunday. This
will provide divergence aloft that will eventually bring some rain
shower activity northward into the Cumberland Valley late Sunday.
The real issue that will remain a issue in the eastern and
northeastern portions of the region will be the strong downslope
flow off the Smokies. Given this have been slow to progress
precipitation into the region Late Sunday into Sunday night. Also,
did opt to lower QPF Sunday night given the same issues.

.LONG TERM...(Monday through Saturday)
Issued at 340 PM EDT SAT APR 21 2018

Closed upper level low to our southwest will slowly rotate into
the area Monday into Tuesday. Strong southeast flow will be in
place at the start of the period with some upper level divergence
spreading across the area. Low levels will be tough to saturate
given the strong flow coming off the Smokies, but the upper level
divergence may be enough to produce a hundredth or two of an inch
of precipitation Monday morning. Most of the day should be dry
with the strong southeast flow. With this said, left a window of
higher pops in the morning with the divergence aloft, but went
drier into the afternoon and evening hours as the flow strengthens
and we lose the upper level support. The southeast flow continues
Monday night. Models continue to be generous with the rainfall,
but until the flow becomes more southwest or west later on
Tuesday, we may be hard pressed to get much shower activity. Did
bump highs up a good 5 degrees on Monday with the strong southeast
downslope flow in play. We will see some rain chances on Tuesday
as the upper level low rotates into east Kentucky. A shortwave
trough will act to finally kick things out by Wednesday with rain
chances coming to an end later in the day.

Models are still in great disagreement late next week, but are
trending towards a strong shortwave trough that may bring a period
of rain to the area followed by a decent shot of colder air. Just
how cold depends on the strength of the trough. At this point no
plans to mention any freeze or frost concerns with so much
uncertainty.

&&

.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
ISSUED AT 747 PM EDT SAT APR 21 2018

A nearby surface high across the Great Lakes, and an upper level
ridge axis extending from the Gulf Coast into the Upper Midwest
will lead to VFR condition for this TAF period. Winds will remain
light and variable through the period. SCT to BKN middle level
clouds, with based between 15 and 20k, may move across the area
from tomorrow morning through the end of the TAF period.

&&

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

$$

UPDATE...AR
SHORT TERM...DJ
LONG TERM...KAS
AVIATION...AR