663
FXUS63 KJKL 031127
AFDJKL

AREA FORECAST DISCUSSION
National Weather Service Jackson KY
727 AM EDT Thu Jul 3 2025

.KEY MESSAGES...

- Enjoy sunny, comfortable weather through Thursday night, with
  highs in the mid-to-upper 80s and pleasant overnight lows.

- Independence Day Friday will be delightful, starting mild with
  some valley fog that clears to sunshine, then temperatures
  warming into the upper 80s to low 90s for the afternoon.

- Prepare for hotter and more humid conditions this weekend, as
  temperatures will climb into the lower and middle 90s.

- Scattered to numerous thunderstorms become a daily possibility
  across all of Eastern Kentucky from Monday through Wednesday.

&&

.UPDATE...
Issued at 727 AM EDT THU JUL 3 2025

Just a quick refresh of the forecast grids to incorporate the
latest morning guidance. Updated the morning text and radio
products to reflect the changes. Grids have been saved and sent.

UPDATE Issued at 1230 AM EDT THU JUL 3 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.
For a time, the PoPs and Wx grids had a couple of showers and
sprinkles in the far east during the evening but now those have
dried up and been removed. These minor adjustments have been sent
to the NDFD and web servers along with a freshening of the zones
and SAFS.

UPDATE Issued at 745 PM EDT WED JUL 2 2025

23Z sfc analysis shows high pressure is now in control of the
weather over eastern Kentucky. This is working to settle the winds
and keep skies mostly clear. Currently temperatures are running
in the upper 70s to lower 80s. Meanwhile, amid northwest winds of
around 5 mph, dewpoints are generally in the low to mid 60s, most
places. Have updated the forecast mainly to add in 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 zones and SAFs.

&&

.SHORT TERM...(This evening through Thursday night)
Issued at 241 PM EDT WED JUL 2 2025

The latest surface analysis across the CONUS reveals a dome of
surface high pressure situated over much of the central United
States. A quasi-stationary frontal boundary extends from northeast
to southeast, oriented parallel to the Atlantic Seaboard. Locally,
our weather will remain under the influence of this surface high-
pressure regime, ensuring warm and dry conditions through the
remainder of the forecast period.

Throughout the remainder of today, the surface high pressure will
continue to build into the forecast area, maintaining warm and dry
weather. Todays high temperatures are expected to reach the mid to
upper 80s. Fortunately, upper-level northwesterly flow will advect
drier air into the region, which will keep heat indices closer to
the actual ambient temperatures. The influence of CAA will be more
pronounced in the overnight hours, with low temperatures forecast to
fall into the low to mid-60s. As is common during summer nights,
widespread valley fog can be anticipated overnight.

Thursday will feature a continuation of this weather pattern as the
ridge of high pressure persists over much of the CONUS. Temperatures
for Thursday will again be warm, with highs forecast to be in the
mid to upper 80s. Similarly, the drier northwesterly flow will
continue to keep heat index values near the actual temperatures.
Thursday night lows are forecast to be slightly warmer, settling
into the mid-60s, accompanied by widespread valley fog.

In summary, surface high pressure will build into the region,
ushering in dry weather with high temperatures climbing into the mid-
80s. Overnight lows will generally remain in the low to mid-60s,
with widespread valley fog expected.

.LONG TERM...(Friday through Wednesday)
Issued at 355 PM EDT WED JUL 2 2025

The long-term period commences with fair weather across Eastern
Kentucky for Independence Day. Analysis based on the 02/12Z model
suite reveals a robust 500 hPa ridge axis extending from the Gulf
of America northward through the Mississippi River Valley and into
Northern Ontario early in the day. An associated ~1021 mb surface
high, though centered over Lower Ontario, exerts a broad calming
and drying influence from southwestern Quebec to the Lower
Mississippi Valley. At the low-levels, weak northerly flow
continues to advect a warm, dry continental air mass into Central
Appalachia.

The ridge axis will pass overhead Friday into Friday night, while
the attendant surface high migrates east of the Appalachians. In
the wake of the departing surface high, low-level flow will become
southerly, initiating the advection of an increasingly moist air
mass northward from the Gulf of America. Precipitable water
(PWATs) values are modeled to rebound to between 1.5 and 1.8
inches (75th to 90th percentile relative to climatology) from
Monday through Wednesday. As this heightened moisture feeds into
the region, the ridge aloft will flatten and develop a weakness
over our area on Sunday as Pacific shortwave trough transits the
Northern Plains/Upper Midwest. This setup will allow for the
first possibility of deep convection by Sunday afternoon, though
any activity would be very isolated and more probable near the
Kentucky/Tennessee border. Confidence is increasing that the
shortwave will fill as the associated weak cold front settles
into the Ohio Valley on Monday. The front is then expected to
stall over or just southeast of the JKL forecast area, as strong
ridging persists to our southeast. The parent shortwave aloft will
be briefly replaced by quasi-zonal to weakly ridged flow before
another Pacific shortwave trough approaches mid-week. This
disturbed pattern will maintain a daily threat of deep, diurnally-
modulated convection over the Eastern Kentucky Coalfields and
adjacent areas from Monday through Wednesday.

In sensible terms, expect a delightful Independence Day morning,
with lows in the lower to middle 60s and some fog in the favored
valley locales. However, temperatures will rise quickly under the
direct early July sun (once any early morning valley fog
dissipates) reaching between 89 and 94 degrees for most locales
during the afternoon. Only a few scattered shallow cumulus and
high, wispy cirrus clouds are expected, as humidity levels remain
tolerable (dew points are forecast to remain in the 60s).
Independence Day evening and night also appear quite pleasant,
with temperatures falling back into the 60s. Some fog is possible
again in the valleys Friday night. Both weekend days are shaping
up to be hot and increasingly humid, with daily maximums in the
lower to middle 90s. There will be an isolated shower or
thunderstorm risk on Sunday, but the vast majority of the area
should remain dry. With the increasing moisture, expect the
diurnal temperature range to tighten early next week, with highs
slipping back into the mid-80s to near 90 by Tuesday and
Wednesday, while nighttime lows moderate to near 70 degrees. The
rise in humidity will lead to widespread heat indices reaching
well into the 90s each afternoon from Saturday through Tuesday.
The renewed muggy air mass will also be accompanied by a daily
threat of scattered to numerous showers and thunderstorms from
Monday onward.

&&

.AVIATION...(For the 12Z TAFS through 12Z Friday morning)
ISSUED AT 645 AM EDT THU JUL 3 2025

River valley fog this morning is resulting in some visibility
reductions for a few of the more fog prone sites through 13Z. VFR
conditions prevail through the remainder of today. Winds will be
light and variable through the period.

&&

.JKL WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

UPDATE...VORST
SHORT TERM...VORST
LONG TERM...GEERTSON
AVIATION...GUEST