161
FXUS63 KJKL 121322
AFDJKL

AREA FORECAST DISCUSSION
National Weather Service Jackson KY
922 AM EDT Mon Oct 12 2026

.KEY MESSAGES...

- Areas of dense fog will clear out by mid morning along with a
  lifting and break up of the low clouds by early afternoon.

- Warm and mostly dry weather dominates the early part of the
  week.

- Rain potential returns by mid to late week, followed by much
  colder weather inbound for this upcoming weekend.

&&

.UPDATE...
Issued at 922 AM EDT MON OCT 12 2026

Have updated to initially increase sky cover greatly this morning
due to fog and low clouds which will linger. This will also slow
the rise in temperatures.

UPDATE Issued at 730 AM EDT MON OCT 12 2026

As the low clouds cleared from west to east, areas of fog took
their place and became locally dense. An NPW is in effect for
locations generally along and west of I-75 with an SPS for places
to the north and east of the advisory. Otherwise, no significant
changes were made to the forecast with the inclusion of the
latest obs and trends for the T/Td/Sky grids. These minor
adjustments have been sent to the NDFD and web servers along with
a freshening of the SAFs and zones.

&&

.SHORT TERM...(Today through Tuesday)
Issued at 520 AM EDT MON OCT 12 2026

08Z sfc analysis shows weak high pressure building into the area
from the southwest. This is not enough to clear out much of the
low level moisture this night and resulted in plenty of low
stratus clouds (and patchy drizzle) covering the bulk of eastern
Kentucky. Only recently have they started clearing out from west
to east. The trouble is as the clouds retreat areas of fog quickly
develop and become locally dense. At this point an advisory is in
effect roughly from I-75 corridor on west but this may need to be
expanded towards dawn should this process push further east.
Amid light southwest winds most places, temperatures and
dewpoints are fairly uniform in the upper 50s to lower 60s.

The models, and their individual ensemble suites, continue to be
in rather good agreement aloft through the short term portion of
the forecast. They all depict troughing departing to the east with
5h ridging quickly building into Kentucky from the southwest.
While the heights do rise aloft over the area, for the most part
northwest mid-level flow will be the rule through Tuesday though
the more distinct impulses stay well off to the north of the JKL
CWA. Once again, given the relatively small model spread, most of
the forecast grids came from unadjusted NBM data this morning.
However, did dry out the dewpoints a bit extra this afternoon and
Tuesday while also adding in some terrain enhancements tonight.
As for PoPs, they were basically escorted out of the region this
morning in line with the NBM and CAMs guidance.

Sensible weather will feature a foggy start in the western parts
of the forecast area. This all clears out by mid morning with the
lower clouds likely disipating towards noon. Look for the
afternoon sunshine arriving from west to east to help
temperatures soar much higher than we saw on Sunday with readings
reaching the low 80s in the west and mid to upper 70s in the east.
For tonight, we will likely see more of a traditional radiational
cooling night resulting in a small to moderate ridge to valley
temperature difference setting up along with fog mainly confined
to the valleys. Tuesday looks amazing with warm temperatures
topping out in the low to mid 80s most places under partly sunny
skies.

The main changes to the NBM starting point were made to allow for
a bit more afternoon drying in the dewpoints and RH for today and
Tuesday along with ridge and valley distinctions tonight. Did not
end up adjusting the PoPs much from the NBM as they appear
reasonable - clearing out this morning then dry through at least
Tuesday evening.

.LONG TERM...(Tuesday night through Sunday)
Issued at 400 AM EDT MON OCT 12 2026

The extended period unfolds Tuesday evening through next Saturday,
shifting eastern Kentucky from unseasonably warm weather early
in the week to a sharp early-autumn frost/freeze potential by next
weekend.

On Tuesday evening, a strong upper-level ridge will remain
anchored across the Southeastern US and Gulf Coast with 500 hPa
heights well exceeding the 90th percentile relative to climo.
Meanwhile, at the surface, broad high pressure positioned off
the Atlantic Coast will maintain steady south-southwesterly
return flow across eastern Kentucky. This pattern will yield
continued warm, dry, and summer-like conditions for mid-October.
Afternoon highs on Wednesday will climb into the 80s, roughly 10
to 15 degrees above seasonal normals. Wednesdays forecast high
temperature of 83F at the JKL airport exceeds the current daily
record of 82F. Model soundings Tuesday and Wednesday show steep
low-level lapse rates from the surface to 850 hPa, with a
pronounced dry layer above the boundary layer. To account for
this boundary layer mixing, raw model guidance was blended with
the NBM to slightly lower dew points both afternoons.

Farther west, an upper-level trough ejecting from the Rockies
into the Northern Plains will push an initial, slow-moving
surface cold front into the Ohio Valley late Wednesday. Cloud
cover should gradually increase Wednesday afternoon from the
northwest, with rain shower chances slowly ramping up Wednesday
evening into Thursday morning.

Some model spread remains regarding Thursday and beyond, driven
by ensemble differences in the strength of the Southeast ridge
and the timing of the ejecting Plains shortwave. The initial cold
front entering the Ohio Valley late Wednesday is shown by a
majority of models to stall and briefly lift back north as a
warm front on Thursday ahead of an approaching surface wave.
However, some solutions are slower. Slight chance to chance
PoPs are forecast through Thursday night.

The cold front then sweeps across eastern Kentucky on Friday.
Shower and thunderstorm chances accompany the frontal passage.
Winds could be breezy at times, with gusts likely in the 20 to
30 mph range for many. The probability of the JKL CWA seeing
gusts exceeding 30 mph currently ranges from a 40 to 60 percent
chance in the latest 12Z LREF ensemble guidance. Strong
post-frontal cold air advection (CAA) will surge into the
Commonwealth Friday afternoon and evening. Any rain chances
should diminish Friday night as low-level moisture grows
increasingly shallow and temperatures drop into the upper 30s
and lower 40s.

While there remains a great deal of uncertainty between
individual deterministic models (mainly the ECMWF and GFS),
ensemble cluster guidance shows overall good agreement on a deep
troughing pattern on Saturday. While GEFS-heavy clusters hold
onto cold northwest flow and low-level post-frontal clouds
slightly longer into the afternoon, dominant EPS/CMC clusters
favor faster eastward progression of the trough axis,
promoting clearing from west to east as a strong surface high
builds in from the Plains. The NBM has the area cooling 15 to 20
degrees from Friday to Saturday, with eastern Kentucky
remaining under continuous northerly cold air advection (CAA).
Highs in the mid to upper 50s on Saturday will run 10 to 15
degrees below climatological normals. If guidance holds,
clearing Saturday night with a strong surface high centered
nearby would support low temperatures tumbling into the upper
20s to lower 30s, effectively ending the growing season, at
least in the sheltered valleys. This will be monitored, and if
guidance holds and confidence grows, frost or freeze products
may be forthcoming by late week.

&&

.AVIATION...(For the 12Z TAFS through 12Z Tuesday morning)
ISSUED AT 750 AM EDT MON OCT 12 2026

Low ceilings, generally corresponding with LIFR or VLIFR
conditions, will lift or erode from west to east during the
morning. Fog to the west of the clearing line will also break up
by mid morning. Via this process conditions will become VFR by
afternoon and continue into the night. Late tonight we may see new
restrictions from areas of fog impacting a few of the TAF sites.
Winds will be light and variable through the period.

&&

.JKL WATCHES/WARNINGS/ADVISORIES...
Dense Fog Advisory until 11 AM EDT this morning for KYZ058-068-
069-079-080-083-084.

&&

$$

UPDATE...HAL/GREIF
SHORT TERM...GREIF
LONG TERM...GINNICK/GEERTSON
AVIATION...GREIF