899
FXUS63 KJKL 050550 AAA
AFDJKL

AREA FORECAST DISCUSSION...UPDATED
National Weather Service Jackson KY
150 AM EDT Thu Jun 5 2025

.KEY MESSAGES...

- Above normal high temperatures persist today, followed by highs
  near to slightly below normal for the weekend.

- Hazy skies linger from distant wildfire smoke aloft.

- Shower and storm chances return today and stay around through
  the upcoming weekend. Some strong storms are possible later
  today, and especially for Fri and Sat with the potential for
  heavy rain and gusty winds.

&&

.UPDATE...
Issued at 130 AM EDT THU JUN 5 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.
These minor adjustments have been sent to the NDFD and web
servers.

UPDATE Issued at 1115 PM EDT WED JUN 4 2025

Hourly grids were again freshened up based on recent observation
trends. Lows still are on track, so overall just minor adjustments
were made at this time.

UPDATE Issued at 845 PM EDT WED JUN 4 2025

Hourly grids were freshened up based on recent observations and
trends. Temperatures were running a few degrees cooler than
forecast in a few locations. Overnight lows remain on track and
some valley fog should again develop along some of the larger
creeks, rivers, and lakes after midnight and linger until a couple
of hours past sunset.

&&

.SHORT TERM...(This evening through Thursday night)
Issued at 421 PM EDT WED JUN 4 2025

Fans of the recent summer-like pattern will need to soak it up
because today is the last we`ll see of it for a bit. High pressure
centered to our east has kept things warm and dry. We`ve seen
another day of above average temperatures in the upper 80s. Skies
are still hazy from lingering Canadian wildfire smoke but
otherwise, our skies are dotted with a scatted cumulus deck that
has developed as we`ve entered the heat of the afternoon. As for
tonight, expect it to be fairly similar to last night. A mild
night with lows in the mid to upper 60s, with our more sheltered
valleys radiating out and making it down to the low 60s and
possibly upper 50s. Though that cooling could be slightly hindered
where clouds move in late in the overnight. Patchy fog is once
again expected to develop in the deeper valleys.

The weather pattern shifts going into Thursday, as a broad upper
level trough starts to push out the ridging that had been prominent
over the area until now. Heights continue to fall through the period
as that troughing moves over the area, before flow eventually
flattens some, while an occasional small wave rides through. At
the surface a frontal boundary stretched through the Upper Midwest
and Mississippi Valley will serve as a focus for showers and
storms while slowly making its way south, occasionally reinforced
by the previously mentioned waves of energy aloft. Tomorrow
afternoon, East Kentucky starts to see the first of that rain as
it enters from the northwest. Chances for rain continue through
Thursday night, but peak in the afternoon with diurnal heating.
Thunderstorms are likely to be spotty/cellular in nature. Some of
them could be capable of producing strong, possibly severe, wind
gusts, but this potential is generally limited to a line through
Montgomery to Rowan Counties and north. This area is where the
storms would be closer to the better forcing and have the chance
to access enough shear to be better organized. Our better chance
for severe weather resides in the long-term portion of the
forecast. Highs Thursday will still be warm, in the mid 80s, but
have the potential to be a little cooler in some spots depending
on the exact timing of increasing cloud cover and storms. Thursday
night is expected to be mild with lows in the mid 60s, but
dreary. Chances for showers and storms continue, particularly in
our northwest, and broken to overcast skies will prevail, keeping
any significant ridge-valley temperature splits at bay.

.LONG TERM...(Friday through Wednesday)
Issued at 512 PM EDT WED JUN 4 2025

The 04/12z model suite upper level analysis beginning Friday morning
shows a broadly-troughed to quasi-zonal pattern over the
Central/Eastern CONUS with multiple embedded disturbances. A
positively-tilted trough axis extends from an ~535 dam low over
northern Quebec through the Northern Plains through the Great
Basin to off the Central California Coast. At the surface, a weak
coastal low is over the Outer Banks. A quasi-stationary front lies
draped from the Maine Coast southwest through the NY/PA Twin
Tiers to just north of the Lower Ohio River and then more westward
to an area of low pressure over KS/OK.

Model agreement is generally good at the synoptic scale through
Sunday. Some increase in model spread is noted thereafter, but
the overall pattern can still be ascertained. The aforementioned
coastal low will drift offshore on Friday, with little direct
impact on our weather. Any shower or thunderstorms activity from
the early morning hours should have exited or be exiting to our
east by 12z. Meanwhile, the stalled frontal boundary will waffle
and slowly ooze southeast on Friday and Saturday as a series of
disturbances ride through aloft. Compared to yesterday, the
frontal boundary`s southward progress appears to have slowed and
there are now likely to be at least 2 rounds of notable rainfall
to end the week, one on Friday afternoon/evening and the other
sometime on Saturday, each with the passing of a stronger vort max
aloft. Forecaster confidence is higher for more widespread and
stronger shower and thunderstorm activity with the first round as
the frontal boundary will still be north of our entire forecast
area and the atmosphere will have time to recover from any early
day convection. Guidance is split on how far south the boundary
will have settled into our area when convection redevelops on
Saturday afternoon. (The more notable activity should occur south
of the boundary). Model sounding data suggests seasonable levels
of destabilization on Friday under partial sunshine -- MLCAPE up
to around 1,500 J/kg -- while EBWD increase to around 30 kts or
perhaps slightly better. This is sufficient for semi-organized
convection with strong to damaging wind gusts the primary severe
threat. Thus, the SPC has placed much of eastern Kentucky under a
Slight Risk for severe weather on Friday and Friday night.
Additionally, the ENS and NAEFS are in good agreement showing
PWATs nearing the 90th percentile relative to climo Friday
evening, corresponding with the passage of the first disturbance.
PWATs are likely to surge again ahead of the second disturbance,
but the northward extent to the maximum moisture is less certain.
The combination of high PWATs, relatively thin CAPE, and the
potential for multiple rounds of downpours has warranted WPC
raising a Marginal risk for excessive rainfall on Friday and
Saturday. Compared to recent model suites, the cold front now
appears to hang around longer Saturday night or even into early
Sunday as it dissipates over or just south of our CWA. This will
keep the threat of diurnally modulated shower and thunderstorm
chances in our forecast for Sunday. Looking ahead to early next
week, the blended guidance shows a potent northern stream 500H
low/trough diving into the Great Lakes and dropping a reinforcing
cold front into the Ohio Valley, reinvigorating the threat of
showers and thunderstorms. Some of the guidance suggests that this
front could stall overhead or nearby later Monday or Tuesday
while a wave of low pressure traverses the region. If this occurs,
soggy weather could persist through at least Tuesday.

Sensibly speaking, for Friday, expect any early morning showers or
thunderstorms to exit east by or shortly after sunrise. At least
partial sun in the morning then yields to rising chances of
showers and thunderstorms that will then linger well into Friday
evening or perhaps later. The main threats with the more intense
activity would be heavy rainfall and strong to damaging wind
gusts. High temperatures are forecast to range in the lower to
middle 80s at most locations. Shower and thunderstorm chances,
most numerous in the afternoon linger for Saturday and, to a
lesser degree, on Sunday. High temperatures both weekend days will
be slightly cooler, mainly upper 70s to around 80F. More
widespread shower and thunderstorm chances return Monday into
Tuesday. High temperatures initially return to the lower and
middle 80s for highs on Monday before settling back closer to 80F
for Tuesday and Wednesday. Nighttime minimum temperatures in the
60s can be expected through Monday night with mid 50s to lower 60s
for Tuesday night.

&&

.AVIATION...(For the 06Z TAFS through 06Z Thursday night)
ISSUED AT 150 AM EDT THU JUN 5 2025

Sfc and upper level high pressure will depart to the east of the
area early in the period while a series of disturbances and a
slow moving front begins to gradually approach eastern Kentucky.
Through the rest of the night, mainly high and some mid clouds
will pass overhead through 15Z. Some fog is possible early this
morning in the typical valley locations through 13Z, with TAF
sites not expected to be affected significantly, but there
remains a small chance for KLOZ and/KSME to briefly dip to MVFR
visibility levels around sunrise. Some showers and/or storms
could encroach on the TAF sites during the 16Z to 18Z timeframe,
with chances of this highest at KSYM before 18Z. PROB30 groups for
scattered convection were used for this threat. Winds into the
morning will be light and variable and continue that way for most
of the period with the exception of briefly stronger sustained
winds and gusts in any showers and thunderstorms.

&&

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

&&

$$

UPDATE...GREIF
SHORT TERM...HAS
LONG TERM...GEERTSON
AVIATION...JP/GREIF