633
FXUS63 KJKL 131914
AFDJKL

AREA FORECAST DISCUSSION
National Weather Service Jackson KY
314 PM EDT Sun Jul 13 2025

.KEY MESSAGES...

- High temperatures will range from near to slightly above normal
  through next week.

- The potential for showers and thunderstorms will persist for the
  next week, especially during afternoon and evening hours.

&&

.UPDATE...
Issued at 834 AM EDT SUN JUL 13 2025

The forecast is updated to reflect the latest radar trends with
spotty showers over the area. More development should occur
during the day after diurnal destabilization occurs.

UPDATE Issued at 1230 AM EDT SUN JUL 13 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
along with a touch up to the PoPs and Wx through the rest of the
night per the current radar images and CAMs guidance. These minor
adjustments have been sent to the NDFD and web servers along with
a freshening of the zones, HWO, and SAFs.

UPDATE Issued at 840 PM EDT SAT JUL 12 2025

00Z sfc analysis shows weak high pressure to the south of the
state and lower pressure to the northwest. The latest semi-
organized cluster of storms is steadily shifting east through the
state and starting to impinge on the JKL CWA with gusty winds the
main concern. Otherwise, only isolated convection is noted across
the area and skies are mostly clear. In addition, just light and
variable winds are seen - outside of any of the storms. Currently
temperatures vary from the lower 70s in the east where the storms
moved through earlier to the still mid 80s in the western
Cumberland Valley region. Meanwhile, dewpoints are generally in
the sticky lower 70s. Have updated the forecast mainly to add in
the latest obs and trends for the T/Td/Sky grids along with an
adjustment to the PoPs through the night per the current radar
images and CAMs guidance. These relatively minor adjustments have
been sent to the NDFD and web servers along with a freshening of
the zones and SAFs.

&&

.SHORT TERM...(Through Sunday night)
Issued at 230 PM EDT SAT JUL 12 2025

Current surface analysis across the CONUS is quite active, with a
surface perturbation moving across its northern half. The main
synoptic feature is a surface low tracking across the Great Lakes
region. Currently, its positioned over Michigan`s Upper
Peninsula. The warm front extends west to east from the lows
center, across Canada, and into New England. The corresponding
cold front stretches southwestward from the lows center, reaching
down to the southern Central Plains. Locally, eastern Kentucky is
firmly within the warm sector regime, behind the warm front but
ahead of the approaching cold front. This setup will lead to
warmer temperatures as southwesterly flow advects warmer
temperatures and higher dew points into the region. This is
already reflected in current temperatures, which have climbed into
the mid to upper 80s.

Through the remainder of the day, temperatures will continue to
climb into the upper 80s to lower 90s. However, throughout the
afternoon, there will be increasing chances for showers and
thunderstorms. Some of these have already started to develop but are
short-lived. The SPC has issued a Marginal Risk for severe
thunderstorms today, as this afternoons convection could bring an
isolated threat of a stronger storm. Any storms that do develop
could bring strong, gusty winds and heavy rainfall. However, since
shear values are nonexistent to negligible, widespread severe storms
are not expected. Showers and storms will dissipate toward the
overnight hours, leading to a mostly dry night with areas of fog and
overnight lows in the upper 60s to low 70s.

Sunday will bring another day of highs in the mid to upper 80s, with
increasing threats for convection as the front finally moves into
the region. As with Saturday, strong storms are possible, but shear
continues to be lacking; therefore, significant severe weather is
not anticipated. Models indicate the front will stall out across the
area from northeast to southwest. As this occurs, PoP chances will
continue from Sunday afternoon through the overnight into Monday.
Sunday night will closely mirror Saturday night, with lows in the
upper 60s to low 70s.

Overall, the period will be highlighted by rounds of showers and
storms, some of which could be severe. Highs will climb into the
upper 80s to lower 90s, with overnight lows falling into the upper
60s to lower 70s, along with areas of fog.

.LONG TERM...(Tuesday through Sunday)
Issued at 314 PM EDT Sun Jul 13 2025

When the long forecast period opens on Tuesday morning, an upper
level ridge will have nudged its way into Southern Kentucky. Thus,
Tuesday looks to be the driest day in the long term forecast period,
albeit the afternoon hours are still marked by scattered
shower/storm chances. After any leftover clouds from Monday`s
activity and the AM valley fog burn off, efficient diurnal warming
processes should yield notably warmer highs near 90. This exceeds
the convective temperature thresholds visible in modeled BUFKIT
soundings, but a lack of dynamic support aloft and only marginal
amounts of CAPE should limit the impacts of Tuesday`s
showers/storms. That activity should begin to subside after sunset
and as overnight low temperatures cool down towards 70 degrees.

For the rest of the long term forecast period, the guidance suite
collectively resolves a stagnant weather pattern over the eastern
half of the country. A broad anticyclone is forecast to remain
parked over the Southeastern states, whereas zonal flow will move
through the Upper Midwest and into the Great Lakes. The Ohio River
Valley will be situated between the two, and our sensible weather
will accordingly be driven by characteristics of both. Southwesterly
flow in the lower levels of the atmosphere will persistently advect
a warm, moist airmass into the Commonwealth, keeping temperatures
and humidity high. This will lead to above-normal PWATs and
increasingly oppressive heat indices on Wednesday and Thursday.
Expect afternoon highs in the low 90s on both days and peak heat
indices in the upper 90s in the deepest valleys and urban corridors.
These warm/humid conditions will combine with some shortwave
impulses moving through the broader zonal flow to enhance
precipitation chances across the area on Wednesday and Thursday.
Thunderstorms will be possible, but they are likely to remain pulse-like
in nature. Weak winds aloft and dry air in the column will mitigate
deep-layer shear and thus the potential for highly-organized
convection. This is particularly true for southern KY, which will be
closer to the center of the southeastern ridging.

Thus, the greatest sensible weather impacts over the area next week
will likely come from the cumulative nature of the heat and the
repetitive nature of the precipitation chances. Rain chances will
peak every day in the afternoon/evening hours, and the heaviest
showers could provide some localized relief from the hot apparent
temperatures. However, overnight lows near 70 degrees will provide
limited nocturnal relief. The NWS HeatRisk tool has been picking up
on the potential for heat-related health impacts across Eastern
Kentucky in the Wednesday-Thursday time frame. Likewise, WPC has
outlined the forecast area in Marginal (Level 1/4) Excessive
Rainfall Outlook on both Wednesday and Thursday. The potential for
localized flash flooding will be highest in areas that see multiple
rounds of heavy rain multiple days in a row next week, as soils in
those places will progressively be able to absorb less moisture.

Guidance suggests that the SE ridge may flatten late next week and
allow a weak frontal boundary to slide into the forecast area. This
could yield slightly cooler afternoon highs in the 80s, but a lack
of deep upper level support means that said front is likely to stall
out. This will keep diurnally-peaking rain chances in the forecast
for next weekend, and we will closely monitor the potential for any
potential excessive rainfall-related impacts as the mesoscale
details of the forecast become clearer by mid-week.

In short, expect an active summertime weather pattern to persist
across Eastern Kentucky this week. Confidence is high that Eastern
Kentucky will experience seasonably warm/humid conditions and daily
diurnal peaks in shower/storm chances throughout the next week. Only
minor adjustments were made to the NBM-populated long term forecast
grids, as it is capturing the general pattern well. Confidence in
the magnitude of overnight ridge-valley temperature splits is low
due to the potential for lingering clouds from diurnal convection.
Likewise, nocturnal fog may form in locations with wet grounds
beyond the typical river valleys. With that being said, grid edits
were limited to minor reductions in valley low temperatures, minor
increases in ridgetop low temperatures, and the addition of valley
fog in the weather grids.

&&

.AVIATION...(For the 06Z TAFS through 06Z Sunday night)
ISSUED AT 630 AM EDT SUN JUL 13 2025

Although a spotty SHRA cannot be ruled out early in the period,
most sites remain dry until this afternoon when some spotty
diurnally-driven SHRA/TSRA activity once again sprouts about by
the afternoon. Have handled this with PROB30 for now given ISO
coverage.

VFR conditions prevail across all TAF sites at issuance as fog
remained confined to area river valleys. VFR Cu will increase by
late morning through the daytime. By late this evening into
tonight, some additional ISO SHRA/TSRA will be possible, although
the greatest coverage should remain N of the terminals. Have
added a PROB30 to account for this potential. Lastly, winds will
be light and variable outside of any convection.

&&

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

&&

$$

UPDATE...HAL
SHORT TERM...VORST
LONG TERM...MARCUS
AVIATION...ILN