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215
FXUS63 KJKL 092007
AFDJKL

AREA FORECAST DISCUSSION
National Weather Service Jackson KY
407 PM EDT Wed Jul 9 2025

.KEY MESSAGES...

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- There is an elevated concern for high water and isolated flash
  flooding across the area into tonight due to torrential
  downpours and possible training of showers and thunderstorms.

- High temperatures will be near normal through the week as
  humidity increases.

- Chances for shower and storms persist through the upcoming
  weekend, mainly during each afternoon and evening.
-- End Changed Discussion --

&&

.SHORT TERM...
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(This evening through Thursday night)
Issued at 407 PM EDT WED JUL 9 2025

At 4 PM EDT, regional radar mosaic shows the more organized
convection from earlier in the day now in Virginia/West Virginia.
Looking aloft, this activity appears to have been forced, at least
in part, by a stronger pulse of energy ejecting northeast out of
a 500 hPa trough that currently extends from James Bay south
through Lower Michigan and Western Kentucky. Additional shower and
thunderstorm activity has developed and is moving over Eastern
Kentucky ahead of another modest pulse of mid-level energy. Over
much of the area, several hours of partial sunshine have allowed
temperatures to heat up into the 80s and generate about 1,000 to
2,000 J/kg of MLCAPE. PWATs still around 1.9 to 2.0 inches along
with a deep warm cloud layer favor torrential rainfall under the
stronger convection. Additionally, nearly unidirectional flow
through the cloud-layer as well as weak upwind propagation vectors
favor back building and training.

The upper level trough will fill as it slowly slides into the
Mid-Ohio Valley tonight and exits east on Thursday morning, taking
the higher PWATs with it. However, until that trough axis
departs, there will be a continued threat for torrential
downpours, leading to isolated flash flooding, even into the
overnight. Another subtle mid-upper level disturbance will
approach Thursday afternoon/evening with the renewed threat of
showers and a few thunderstorms, but PWATs will be much lower,
around 1.25 to 1.50 inches, north-to-south, which should minimize
any further excessive rainfall threat. At nighttime, abundant low-
level moisture will combine with any clearing of the clouds to
promote radiation fog formation, with the most favored locations
being in typical valley locales.

In sensible terms, the warm, muggy and unsettled July weather
pattern will continue through the short-term. Look for showers and
thunderstorms to gradually diminish this evening/overnight,
though they could linger deep into the night for a few locations.
Torrential downpours in the strongest activity could lead to
isolated instances of flash flooding. It will be mild and muggy
with areas of fog and lows in the mid 60s to around 70 degrees. On
Thursday, look for partial sunshine giving way to rising shower
and thunderstorm chances during the late morning/afternoon, most
likely near the Kentucky/Tennessee and Kentucky/Virginia borders.
Conditions will again be warm and humid with high temperatures in
the middle 80s for most locations. Rain chances taper off again
Thursday evening and night with partial clearing and areas of fog
developing overnight. It might be a bit cooler with low
temperatures ranging in the mid to upper 60s.


.LONG TERM...(Thursday through Tuesday)
Issued at 425 PM EDT TUE JUL 8 2025

The long period is expected to begin with an upper level ridging
centered in the western Atlantic near Bermuda with a trough off
the southeast U.S. coast, troughing extending from Quebec across
the eastern Great Lakes to the Lower oH Valley to the Arklatex
region, with another upper level ridge centered near the CA and
Mexican border and extending from the southwest Conus into the
Pacific. At that point, a shortwave trough is expected to be in
the MN to IA vicinity with a stronger shortwave extending from an
upper low in northern Canada to the interior Northwest/northern
Rockies. At the surface, an area of low pressure should initially
be over the eastern Great Lakes vicinity with a frontal zone east
to off the New England/Northeast U.S. coast with the trailing
cold front toward the OH Valley region, but likely north of the OH
River and then west to the mid MS valley and portions of the
Central to northern Plains/Dakotas. Another sfc low centered in
the Manitoba vicinity should be in place ahead of the troughing in
western Canada.

For Thursday to Friday night, the axis of troughing at 500 mb
should shift north and northeast of the Lower OH Valley and
eastern KY from Thursday to Thursday night as upper troughing
moves toward the Maritimes and northeast. The next upstream
shortwave may move from the upper MS Valley vicinity to the Great
Lakes and generally pass north of eastern KY on Friday with
generally rising heights at 500 mb progged across eastern KY at
that point. Further west and southwest, upper level ridging
should encompass much of the western Conus and become centered a
bit further west off the CA to Baja coast. Meanwhile through
initially from central Canada to the Northwest Conus should move
east to the Hudson Bay to western Ontario region to portions of
the Northern and Central Plains to upper MS Valley. As this occurs
the boundary initially north and northwest of eastern KY should
sag a bit south into the Mid Atlantic states to portions of the OH
Valley though likely remaining north of the OH River through
Thursday into Friday. Though as troughing works across portions
of Canada and toward parts of the Northern Plains and Central
Conus that boundary should lift north and northeast of eastern KY
as a warm front with a sfc low organizing in the Plains and
tracking toward the Upper MS Valley/western Great Lakes with the
trailing frontal zone extending to the mid MS Valley to Southern
Plains at that point. With the rising heights from the Southeast
and into parts of the Appalachians during this timeframe, a sfc
ridge of high pressure is anticipated to build from the northeast
Gulf to the Southeast and Southern Appalachians during this
timeframe. With the rising height trend at 500 mb from Thursday to
Friday, Friday should be the warmer of the two days. The initial
trough/shortwave crossing the region should help to fire largely
diurnally driven convection for Thursday while the next trough
passing generally north with the frontal zone in the vicinity
should lead to some additional at least scattered convection on
Friday also likely peaking during the afternoon and evening.

Saturday to Sunday night, upper troughing is progged to move east
across Ontario to Quebec, the Great Lakes and OH Valley to the
Northeast to Mid Atlantic with upper ridging building into the
Southeast as the weekend progresses and remains in place from the
eastern Pacific to the western Conus. Additional troughing in
between the ridging is generally expected to develop from the
Central to southern Plains Sunday to Sunday night. At the surface,
low pressure should trek across the Northern Great Lakes to
Ontario and Quebec while the weakening trailing cold front moves
to the Central to eastern Great Lakes and the OH Valley region and
becomes diffuse by the end of the weekend. Additional rounds of
convection are anticipated across eastern KY during this timeframe
as well. There is a general consensus of a slight max in
convective probabilistic guidance from the GEFS and ENS for
Saturday across eastern KY. However, shear is expected to remain
limited this weekend as it will be this week and into early next
week and thereby limiting the potential for any organized
stronger convection. Highs over the weekend should be near normal
with a general peak in convection anticipated each afternoon and
evening though with the trough moving into and across the area,
some convection cannot be ruled out on Saturday night and into
late Sunday evening or Sunday night.

During the Monday to Tuesday timeframe, guidance has rising
heights 500 mb heights from the Southeast into the OH Valley, TN
Valley, and portions of the Appalachians while the axis of weak
troughing between that ridging and ridging from the Southwest
Conus to the eastern Pacific is over portions of the Plains/Central
Conus. This upper ridging with a ridge of sfc high pressure from
the northeast Gulf across the Southeast to the mid Atlantic should
result in a warming trend with more in the way of capping compared
to earlier in the long term period. The result should be near or
below average mainly diurnally driven pops for mid July with high
temperatures trending above normal by Tuesday to near or in excess
of the 90 degree mark for many locales.
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&&

.AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon)
ISSUED AT 210 PM EDT WED JUL 9 2025

Scattered to locally numerous showers and thunderstorms are
anticipated through 00z across most of eastern Kentucky. While
MVFR to VFR conditions will generally prevail, brief but
significantly worse conditions are possible in torrential
downpours associated with stronger showers and storms. Areas of
fog are likely again tonight with MVFR/IFR or worse visibilities,
especially at locations which experience decent clearing of cloud
cover after afternoon/evening rainfall. 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