Myra, Kentucky Weather Forecast Discussion

594
FXUS63 KJKL 070531
AFDJKL
AREA FORECAST DISCUSSION
National Weather Service Jackson KY
131 AM EDT Sun Sep 7 2025
.KEY MESSAGES...
- Extensive fog will be around through the night and likely be
  locally dense in the valleys.
- Below normal temperatures and drier weather return for the
  latter part of the weekend behind a departing cold front.
&&
.UPDATE...
Issued at 1235 AM EDT SUN SEP 7 2025
No significant changes were made to the forecast with mainly just
the inclusion of the latest obs and trends for the T/Td/Sky grids
but also to add more extensive fog into the weather grids. These
minor adjustments have been sent to the NDFD and web servers along
with the freshening of the zones, SAFs, and HWO - including an SPS
for fog.
UPDATE Issued at 855 PM EDT SAT SEP 6 2025
00Z sfc analysis shows high pressure building into the area in the
wake of an exiting cold front to the southeast. This is working to
clear the skies from west to east this evening and ending any
lingering sprinkles or drizzle patches. Currently, temperatures
are running in the upper 50s and lower 60s across the area.
Meanwhile, amid light and variable winds, dewpoints vary from the
low 50s northwest to the lower 60s in the far southeast. Have
updated the forecast mainly to add in the latest obs and trends
for the T/Td/Sky grids while lingering the trace pcpn for a tad
longer from JKL on southeast. These minor adjustments have been
sent to the NDFD and web servers along with a freshening of the
zones and SAFs.
&&
.SHORT TERM...(This evening through Sunday night)
Issued at 300 PM EDT SAT SEP 6 2025
Regional radar imagery and surface observations show a fairly
steady light rain falling across nearly all of eastern Kentucky at
mid-afternoon. The back edge of the rain shield is noted from
roughly Vanceburg, KY southwest to Bugtussle, KY. Under this
rain, temperatures are cool, ranging from the upper 50s to lower
60s nearly everywhere except in the deep Cumberland Mountain
Valleys, where values as warm as ~70F are noted. The latest
surface analysis shows a cold front with an anafrontal structure
extending from New York City SSW to over southern Georgia. To our
west, surface high pressure reigns firm across the Central and
Northern Plains, outside of a couple of weak surface trough
features in the vicinity of the Upper Great Lakes. Aloft, a deep
and broad 500 hPa trough is in place over most of the CONUS east
of the Rocky Mountains.
This 500 hPa trough will linger aloft through the short-term,
though its core will become more displaced to the northeast. As a
result, that slow-moving surface cold front will edge southeast
through this evening, with most lingering precipitation tapering
by 21-22Z north of the Hal Rogers/KY-80 corridor. Further
southeast, patchy light drizzly rain could linger several hours
longer, perhaps even close to midnight over the higher mountains
along the KY-VA border. As the rain comes to an end at a given
location, skies will tend to lift and clear but this will be in
the evening or even after sunset for most locations. Due to
lingering low-level moisture and fairly weak winds, any clearing
should favor rapid fog formation, especially in sheltered valleys
and low-lying areas. However fog, may tend to lift into low
stratus overnight due to the thickening fog`s "insulative"
properties trapping outgoing long-wave radiation. A northeasterly
component in the weak near surface flow may also favor low
stratus. Looking ahead to Sunday, surface high pressure will shift
eastward, cresting north of the Ohio River Sunday night. The
drier air will manifest at the surface on Sunday after morning fog
and stratus lifts and scatters, allowing a fair-weather cumulus
field to develop. Quiet conditions persist Sunday night with fog
once again favored in the sheltered river valleys.
In sensible terms, look for light rain to diminish slowly from
the northwest this afternoon and evening. Temperatures should hold
close to current levels through sunset. Skies slowly clear from
the northwest as well this evening into the overnight, allowing
low stratus and extensive fog formation overnight. The fog could
become locally dense in some areas. It will be cooler with low
temperatures ranging from the mid 40s over the Eastern Bluegrass
to the mid 50s in the deep valleys near the Virginia-Kentucky
border. Otherwise, fair weather dominates Sunday and Sunday night
with high temperatures forecast to reach the low to mid 70s during
the afternoon while dew points settle into the 40s -- a splendid
early autumn day. Temperatures are then forecast to dip into the
40s area-wide Sunday night with fog redeveloping in the favored
valleys.
.LONG TERM...(Monday through Saturday)
Issued at 436 PM EDT SAT SEP 6 2025
A cool and dry air mass will still be in place locally to start
the period, as surface high pressure passes eastward over the
upper Ohio Valley and lower Great Lakes region. Aloft, the upper
level trough which allowed for our resurgence of autumn-like air
will be progressing east and retreating northward. Even as the
surface high departs eastward early in the week, it will continue
to ridge southwestward along the Appalachians. This will prevent
any significant low level moisture return, which should continue
to be the case through Saturday. Even though low level
temperature advection will be fairly neutral, a slow warming trend
can be expected as insolation works on the air mass.
A rather minor upper level trough is expected to pass over in the
Wed-Thu time frame. With very little moisture present, it
shouldn`t be strong enough to have any significant effect on our
weather. After this, model agreement starts to take a hit. The
latest deterministic GFS has a weak upper level trough dropping
southeast from the Great Lakes to the Mid Atlantic region in the
Fri-Sat time frame, with a notable increase in mid-upper level
moisture bringing virga. Even if this scenario came to be, it`s
still very questionable if the virga could overcome our dry lower
levels to eventually result in any precip. Meanwhile, the latest
ECMWF has transient ridging aloft building back in by Saturday.
Despite differing solutions, a model blend including ensembles
keeps the POP very low, and the forecast will remain dry.
&&
.AVIATION...(For the 06Z TAFS through 06Z Sunday night)
ISSUED AT 131 AM EDT SUN SEP 7 2025
IFR TAFs are occurring with this TAF issuance. These conditions
will persist through the overnight before gradually improving
Sunday morning. VFR conditions are expected after 14Z and will
remain VFR through the remainder of the period. Winds will be
light and variable through the TAF window.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
UPDATE...GREIF
SHORT TERM...GEERTSON
LONG TERM...HAL
AVIATION...VORST

NWS JKL Office Area Forecast Discussion