-- Discussion containing changed information from previous version are highlighted. --
682
FXUS63 KJKL 101930
AFDJKL

AREA FORECAST DISCUSSION
National Weather Service Jackson KY
330 PM EDT Thu Jul 10 2025

.KEY MESSAGES...

- High temperatures will be near normal through the week though
  they may trend above normal over the weekend and early next
  week.

- Chances for shower and storms persist through the upcoming
  weekend and into early next week, mainly during each afternoon
  and evening.

&&

.SHORT TERM...
-- Changed Discussion --
(This evening through Friday night)
Issued at 330 PM EDT THU JUL 10 2025

Widely scattered showers and thunderstorms (often referred to as
garden variety for their disorganized nature) continue across
parts of central/eastern Kentucky at mid-afternoon. This activity
is occurring as a dampening upper-level trough, extending
southward from Quebec, crosses the Central Appalachians. This
convection is also generally ahead of the last associated weak
mid-upper level vorticity max, which is passing over Central
Kentucky. Meanwhile, there is little in the way of discernible
features in the surface pressure field as it remains dominated by
mesoscale diurnal and convective effects. A stalled frontal
boundary well north of the Ohio River has little direct impact on
our sensible weather. PWATs have dropped sharply since yesterday
and now range from 1.4 to 1.6 inches while flow in the 850-300 mb
layer favors cell motions to the east at about 10 to 15 kts,
limiting hydrologic concerns to very isolated poor-drainage/urban
ponding and elevated small stream flows in locations affected by
the most persistent convection. MLCAPE is modest around 1,000 to
1,500 J/kg and shear is minimal, minimizing the severe weather
concern. Temperatures are seasonable, ranging from the mid 70s in
areas recently affected by convection to the mid 80s where
sunshine has been more prevalent.

As the trough and its associated vorticity energy slowly slide
eastward, low to mid-level heights will begin to rise as weak
subsidence leads to a mid-level capping. This will cause showers
and thunderstorm coverage to gradually wane through the remainder
of the afternoon and evening and actually allow a weak tongue of
high pressure to build along the Central and Southern Appalachian
Mountains tonight. The combination of clearing skies, light winds,
and ample lingering low-level moisture will set the stage for
efficient radiation fog formation. Locally dense fog is not out of
the question as nighttime minimum temperatures are forecast to
fall 2+ degrees below crossover temperatures in many areas. On
Friday, heights continue to rise (aside from a weak upper level
perturbation in the afternoon) while surface ridging slides a
little further east ahead of the next weak upper level trough
approaching from the Central Plains. Limited deep convection is
possible again on Friday afternoon/early evening with the passing
disturbance and differential heating. However, lean CAPE profiles
and minimal shear will keep any activity sporadic and weak. After
bottoming out between 1.2 and 1.4 inches tonight/early Friday,
PWATs will again creep higher amidst southwesterly return flow,
likely exceeding 1.5 inches toward dawn on Saturday.

In sensible terms, look for leftover showers and thunderstorms to
dissipate heading through the evening. Partly cloudy skies yield
to areas of fog overnight. Some of that fog could become locally
dense, especially in valleys. Low temperatures are forecast to be
in the mid to upper 60s. On Friday, mostly sunny skies might be
interrupted in some locations by isolated to scattered showers and
thunderstorms. Otherwise, it will be seasonably hot with highs
from 85 to 90 degrees. Friday night is shaping up similar to the
prior night with any late-day convection giving way to mostly
clear skies and areas of fog overnight. The fog is likely to be
more confined to the river valleys than tonight. Look for Friday
Night temperatures to settle back into the mid 60s to near 70
degrees.


.LONG TERM...(Friday through Wednesday)
Issued at 500 PM EDT WED JUL 9 2025

The period is expected to begin with an upper level ridge
centered over parts of the western Atlantic near or northeast of
Bermuda and extending into the eastern Gulf with another upper
level ridge centered off the CA and Baja coast and extending into
parts of the southwest Conus. In between an upper level trough is
expected to extend into the Northeast Conus to mid Atlantic states
from Quebec with a trend of rising heights into the Southeast and
Southern Appalachians as the period begins. Further west, upper
troughing is progged initially from parts of the upper MS valley
to Central and Southern Plains between the two areas of upper
level ridging. In addition, an upper level trough per the
consensus of guidance should extend from the Hudson Bay vicinity
into MT and portions of the Great Basin with another trough
upstream from the Gulf of Alaska to west of the BC coast. At the
surface, a frontal zone should extend from Quebec to south of the
Great Lakes and north of the OH Valley into the Plains while
another sfc low is anticipated in Ontario as the period begins
with the trailing cold front into the Dakotas to portions of the
western Conus.

Friday to Saturday night, guidance generally has a trend of
rising heights at 500 mb across eastern KY for Friday into Friday
evening/night. During this time, upper level ridging is expected
to continue to extend from near Bermuda to the Gulf and parts of
the southeast Conus with upper level ridging remains from the
Southwest Conus into the eastern Pacific. A weak shortwave may
pass north of eastern KY and across the Great Lakes later Friday
night to early on Saturday while guidance generally has near
neutral height tendencies at 500 mb for Saturday or perhaps some
slight height falls late on Saturday. This will be in advance of
the shortwave moving across portions of Canada and the Northern
Plains reaching western Ontario to the Great Lakes by late
Saturday night. At the same time another shortwave moving around
ridging that builds north across the western Conus as the weekend
begins should move into the Upper MS Valley and portions of the
Northern and Central Plains/Central Conus. Further south, upper
level ridging should become centered from off the Southeast US
Coast to Gulf to begin the weekend. Meanwhile, at the surface, a
ridge of high pressure should be in place from the eastern Gulf to
Southern Appalachians while the boundary initially north of
eastern KY lifts north into Canada as a sfc low tracks to near
James Bay and the trailing cold front moves across parts of the
western and central Great Lakes and sags toward the Lower OH
Valley. Diurnally driven convection is anticipated across eastern
KY with coverage similar to climatology for eastern KY with no
discernible triggers anticipated at this point. Some periods of
height rises and relatively warm temperatures aloft should tend to
limit coverage of convection. Nevertheless isolated to scattered
showers and storms should be a fixture each afternoon and evening.
Also, valley fog is anticipated each night as well. Near normal
temperatures are anticipated to end the work week and begin the
weekend.

Sunday to Monday night, the next upper level shortwave trough
should move east across Ontario and the western and Central Great
Lakes and enter the Lower OH Valley from Sunday to Sunday night
while upper level ridging remains across the Gulf and parts of
the southeast and another upper level ridge remains centered from
the Southwest Conus to the eastern Pacific. This shortwave trough
at 500 mb should work into Quebec and across the eastern Great
Lakes and reach the Maritimes to Northeast and mid Atlantic states
through Monday night. This would have the shortwave trough
crossing the Lower OH Valley and eastern KY later Sunday night to
Monday evening. In advance of this shortwave trough passing a cold
front should sag south of the OH River by later Sunday night and
Monday and perhaps across eastern KY Monday to Monday evening and
then south of the area on Monday night as sfc high pressure
builds to the eastern Great Lakes to portions of the OH Valley
and Appalachians ahead of shortwave upper ridging behind the late
weekend to early week shortwave passage. Somewhat greater
coverage of convection is anticipated as the shortwave trough and
cold front approach and cross the area to end the weekend and
begin next week. Pending the degree of heating in advance of the
front and resultant instability a few stronger storms cannot be
ruled out. Temperatures should remain near normal.

Tuesday to Wednesday, upper and sfc ridging extending from the
Southeast to OH Valley should gradually shift east from Tuesday
into Wednesday with the boundary south of the region becoming
diffuse. Another trough is expected to have moved across western
Canada and across the Northern Plains and into the upper MS Valley
and begin to the western Great Lakes around the middle of next
week. This should be preceded by a sfc frontal zone that works
into the Great Lakes to mid MS Valley late in the period and
may near the Lower OH Valley late. Under the ridging a slight
uptick in temperatures perhaps to a few degrees above normal may
occur across eastern KY. Some diurnally driven convection is also
possible though coverage on Tuesday could be more limited with
ridging dominating. In addition, as on other nights in the long
term period, valley fog development is favored.
-- End Changed Discussion --

&&

.AVIATION...(For the 18Z TAFS through 18Z Friday afternoon)
ISSUED AT 158 PM EDT THU JUL 10 2025

Generally VFR conditions are noted at TAF issuance, though
briefly worse conditions are occurring under scattered diurnally-
driven pop-up convection. Once that convection dissipates this
evening, expect good clearing tonight which will allow for areas
of BR/FG to develop, likely dropping to IFR/LIFR visibility or
worse at valley terminals, though significant reductions will be
possible at the TAF sites as well. Winds will generally be under
10 kts through the period, except locally stronger and erratic
near thunderstorms.

&&

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

&&

$$

SHORT TERM...GEERTSON
LONG TERM...JP
AVIATION...GEERTSON