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022
FXUS63 KJKL 190811
AFDJKL

AREA FORECAST DISCUSSION
National Weather Service Jackson KY
411 AM EDT Thu Sep 19 2024

.KEY MESSAGES...

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- Isolated shower and storm chances will exist this afternoon.

- Above average temperatures, around 10 degrees above normal, is
  expected for the weekend.

- Showers and storms return for the first half of next week.
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&&

.SHORT TERM...
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(Today through Friday)
Issued at 411 AM EDT THU SEP 19 2024

Current surface analysis has surface high pressure firmly entrenched
across the area. This has allowed for mostly clear skies; as well
as, widespread valley fog. Due to the coverage and impacts of the
patchy, dense valley fog; opted to issue an SPS to cover fog
impacts. Temperatures across eastern Kentucky have fallen into the
low to mid-60s with the coldest temperatures being in the far
eastern sheltered valleys of the CWA.

Upper level troughing off the east coast will continue to shift off
to the east throughout the day today. However, lingering very
isolated shower and storm chances will exist this afternoon but
mainly for portions of Pike County. Otherwise, high pressure and
height rises will keep the CWA mostly dry. Also, with high pressure
nudging into the area, temperatures are forecast to climb into the
mid to upper-80s this afternoon. Any showers that do occur this
afternoon will taper off and clearing skies are to be expected.
Which will lead to lows in the mid-60s and upper-50s to low-60s in
the valleys. This will again allow for patchy, dense valley fog
Thursday night that`ll burn off Friday morning.

Height rises and upper-level ridging are expected to continue to
push into the region overnight Thursday into Friday leading to
another dry day with temperatures a little bit warmer. Temperatures
on Friday are forecast to be in the mid to upper-80s with a few
places touching 90. Fortunately, the airmass moving into the region
is drier and therefore, heat indices will be comparable to actual
temperatures.

.LONG TERM...(Friday through Wednesday)
Issued at 425 PM EDT WED SEP 18 2024

The 18/12z model suite analysis beginning Friday morning depicts
a positively-tilted ridge axis extending from an ~592 dam high
over/near Del Rio, TX northeastward across the Lower Ohio Valley
and then northward across western Quebec. At the surface, high
pressure ridging is situated just east of the upper level ridge
and extends from Labrador southward along the spine of the
Appalachians. Upstream, a mean trough dips south from Canada
across the Northern Plains/Northern Rockies. Another closed low is
crossing Southern CA as it rounds the base of the upper level
trough. Ahead of that upper- level trough, a cold front is draped
from an ~992 mb surface low over northeast Manitoba down through
Duluth, MN and Kansas City, MO and westward to near/over the OK
Panhandle.

Ahead of the cold front, west to southwesterly low-level flow will
advect unseasonably warm temperatures (17-19C @ 850 mb) across
eastern KY by Saturday and Sunday. While portions of the area,
primarily near the VA border, have received a wetting rainfall this
week, many locations further north and west remain very dry (soil
moistures remain lower than 10 to 20 percentile in many spots as
per NASA SPoRT-LIS). Given the low soil moisture values,
decreasing evapotranspiration, and fair skies, stronger sensible
heating warranted nudging daily maximum temperatures upward on
Friday through Sunday toward or slightly in excess of the NBM 75th
percentile while also nudging afternoon dew points toward the NBM
10th percentile. This yields high temperatures mainly in the mid
80s on Saturday and then a few degrees warmer for both Saturday
and Sunday when warmer locales could eclipse the 90 degree mark.
This drying pattern will also support moderate ridge-valley
temperature splits developing each night--expect lows in the mid
50s coolest valleys to mid 60s in the thermal belts.

Looking ahead to new work week, the closed low initially over CA
will eject out onto the Plains Sunday and become an open wave riding
northeastward toward the Great Lakes. This system will be
accompanied by a surface wave riding the aforementioned frontal
boundary across the Plains, Great Lakes, and on into Eastern Canada.
Ensemble clustering shows significant spread developing during this
time as members struggle to resolve additional energy of North
Pacific origin diving into the trough, which could encourage
slowing/amplification of the parent trough, while, at the same time,
another tropical system potentially forms over the Gulf of Mexico.
These factors will have significant bearing upon whether the surface
low is able to push the cold front through eastern KY by the end of
the forecast period. That, of course, will have significant sensible
implications in terms of temperatures and rain chances during the
second half of the long-term period. Given the uncertainties, the
portions of the forecast from Monday onward remain very close to the
NBM with only some minor adjustments for topography. Forecast highs
cool from the mid 80s on Monday to near normal, in the upper 70s to
near 80, on Wednesday. However, temperatures could be substantially
warmer or cooler depending upon the how the pattern evolves.
Precipitation probability, timing, and intensity are also
uncertain.
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&&

.AVIATION...(For the 06Z TAFS through 06Z Thursday night)
ISSUED AT 153 AM EDT THU SEP 19 2024

Surface high pressure over much of the area is allowing for clear
skies across the region. This is promoting VFR conditions at
KJKL, KSJS and KSYM. However, valley fog is causing MVFR/IFR
conditions at KSME and KLOZ. These conditions will persist through
the early morning before dissipating and terminals return VFR.
Another round of showers and storms will be possible Thursday
afternoon but confidence in location is lacking; therefore, opted
to keep VCSH out of the TAFs. Aside from isolated shower chances,
VFR conditions are expected to persist through the period with
light and variable winds.

&&

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

$$

SHORT TERM...VORST
LONG TERM...GEERTSON
AVIATION...VORST