Biggs, Kentucky Weather Forecast Discussion

057
FXUS63 KJKL 250025 AAA
AFDJKL
AREA FORECAST DISCUSSION...UPDATED
National Weather Service Jackson KY
825 PM EDT Wed Sep 24 2025
.KEY MESSAGES...
- Rounds of showers and thunderstorms through the night will
  bring heavy rainfall. This rain could lead to isolated flash
  flooding, especially where storms repeatedly move over the same
  areas.
- A few thunderstorms could become strong this evening, with
  gusty winds as the primary concern.
- Periods of showers will continue Thursday. A low chance for
  rain will then linger through the weekend with continued mild
  temperatures.
&&
.UPDATE...
Issued at 745 PM EDT WED SEP 24 2025
23Z sfc analysis shows eastern Kentucky in the middle of an
evolving frontal structure associated with a distinct area of low
pressure lifting east northeast from the Memphis area. Plenty of
cloud cover has kept the instability to a minimum today despite
the potent pattern. As such, there is mainly just a few clusters
of showers around the area this evening. However, the CAMs
consensus is for an increase in activity with more in the way of
thunder later this evening and through the overnight - perhaps
particularly targeting the I-64 corridor. Currently, temperatures
are running in the low to mid 70s. Meanwhile, amid generally
south winds of 5 to 10 mph, dewpoints are in the upper 60s to
lower 70s. Have updated the forecast mainly to adjust PoPs and QPF
through the evening and overnight per the latest CAMs guidance.
Did also add in the latest obs and trends for the T/Td grids.
These 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 235 PM EDT WED SEP 24 2025
The latest surface analysis across the CONUS shows multiple surface
disturbances with associated surface boundaries bringing widespread
showers and storms to much of the eastern CONUS. The first of these
disturbances is a surface low tracking through northeastern Ohio
with a stationary boundary oriented eastward toward the Mid-
Atlantic. The second feature is located over western Kentucky,
riding along the cold front of the Ohio surface low. A third surface
perturbation is over the Ozark Region, also riding along the same
cold front, with its own cold front extending southwestward toward
the Sonoran Desert. Locally, weak showers are riding along the
boundary that is oriented along the Ohio River.
Similar to yesterday, the upper-level flow pattern is consistent
with what is happening at the surface. At 500 hPa, there is a closed
upper-level feature that is favoring the northeast Ohio low, but the
main highlight is a positively tilted longwave trough that is
covering much of the CONUS, east of the Rockies. At the base of this
trough, the western Kentucky low is located in the right exit region
of a 60-knot upper-level jet streak. Southwesterly flow on the
upslope side of the trough is over the forecast area, and this flow
is advecting abundant moisture. Forecast soundings are indicative of
this increased moisture as forecast PWs values are approaching 1.90
to 2.00 inches this afternoon. Other heavy rainfall parameters such
as long, skinny CAPE profiles, high mid- and low-level relative
humidity, and training along a boundary will all combine to create
local hydrological issues across eastern Kentucky. Fortunately,
storm motions are rather high, which favors progressive motion, so
storms do not have a large residence time to produce efficient
rainfall. However, morning and early afternoon CAMs continue to
indicate two potential rainfall maximums through the frontal passage
on Thursday. The first is along the I-64 corridor where training is
forecast this afternoon, and then across the southeast overnight
where training is expected to occur. Total rainfall through the
frontal passage is forecast to be less than 2.00 inches, but areas
that see repeated rounds of showers and storms could exceed that
total, and local instances of flash flooding will be possible. Due
to these conditions, the WPC has the entire forecast area under a
Day 1 Slight Risk for Excessive Rainfall.
Along with this heavy rain threat, there is a very marginal risk for
severe weather. The SPC has largely pulled the Marginal Risk out of
the CWA, but there is still a Marginal Risk for severe storms across
the Lake Cumberland region of south-central Kentucky. As there has
been very little chance to increase instability, the threat for
severe storms will largely be nil. Nonetheless, showers and storms
will continue through the day today, and this will play a role in
temperatures as highs will only climb into the mid to upper 70s.
Widespread cloud cover overnight will keep temperatures mild, and
they will only fall into the mid to upper 60s.
Thursday will bring continued chances for showers and storms as the
cold front slowly moves across the Commonwealth. Showers and storms
will persist throughout the day before the frontal passage occurs
late Thursday afternoon, bringing an end to precipitation late
Thursday evening. Flash flooding and severe weather threats are
essentially zero as precipitation tomorrow appears to be progressive
and forcing is limited by a lack of shear and instability. A surface
high-pressure system will try to nudge its way into the region for
the end of the period, but the upper-level trough will remain in
place.
The forecast period will be highlighted by periods of showers and
storms. The biggest threat will be the heavy rainfall through
Thursday. Otherwise, highs will be in the upper 70s, with overnight
lows falling into the low to mid-60s tonight and the upper 50s to
lower 60s for Thursday night.
.LONG TERM...(Friday through Wednesday)
Issued at 235 PM EDT WED SEP 24 2025
For Friday, a positive upper trough axis will continue to move
slowly into the central and southern Appalachians with the frontal
boundary moving well southeast of the area.  However, an inverted
surface trough will remain just south and east of the area.
Shear axis and associated Q-Vector forcing will keep chances of
showers especially areas near the KY/VA and KY/TN state-lines. CAPE
looks quite limited so thunder chances quite low.
For much of the extended period from Friday through at least Monday
the ensemble cluster analysis along with the latest deterministic
models are showing an upper trough axis being cut-off over the
Tennessee valley and central/southern Appalachians and weakening.
During this period, shear axis will rotate around this upper low
producing periods of better Q-Vector forcing and deformation zone
forcing. An inverted surface trough is also anticipated.
Ensemble CAPE probabilities do increase for Saturday, Sunday, and
Monday with afternoon values of 250-500 possible. This is likely due
to more sunshine in the afternoon hours. End result will be greater
coverage of diurnal showers and possibly thunderstorms. Threat
for strong to severe storms is quite limited. Greatest coverage
will likely remain near the KY/VA and KY/TN state-line.
For Tuesday and Wednesday, confidence is low on how this closed off
and weakening upper low will effect the area. Can not rule out a
slight chance of mainly diurnal convection.
Sky cover becomes less for late this weekend into early next week
which will allow for better radiational cooling conditions so will
modify the mins for the valley/ridge temperature differences.
Nighttime and morning fog will become more likely as well some dense.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
ISSUED AT 825 PM EDT WED SEP 24 2025
TAFs are all VFR at the 00Z issuance but there are clusters of
showers around and per the latest CAMs guidance precipitation
will increase in coverage and intensity for most of the area later
this evening and overnight causing terminals to fall into
categorical IFR to MVFR - staying that way through much of the
TAF window. Showers and storms will begin to taper off toward the
Thursday evening but little improvement in aviation conditions is
expected. Winds will be largely 5 kts or less through the period
generally from the south but gusty and erratic winds can be
expected with any stronger convection.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
UPDATE...GREIF
SHORT TERM...VORST
LONG TERM...DH
AVIATION...VORST/GREIF

NWS JKL Office Area Forecast Discussion