633
FXUS63 KLMK 080542
AFDLMK

Area Forecast Discussion
National Weather Service Louisville KY
142 AM EDT Sat Jun 8 2024

...Updated Aviation Discussion...

.KEY MESSAGES...

*   Showers and a few thunderstorms this weekend. Locally heavy
    downpours possible late Saturday night into early Sunday morning
    across western and southern Kentucky.

&&

.UPDATE...
Issued at 954 PM EDT Fri Jun 7 2024

Sun has just set over central Kentucky and southern Indiana,
allowing gusty southwesterly winds to relax and temperatures to
cool. Clear skies and light winds will lead to efficient cooling.
Low temperatures in the morning are expected to be in the upper 50s
and low 60s. In the early morning, dissipating convection currently
over the central Plains will move over the Ohio Valley bringing
broken to overcast clouds and scattered light showers by mid-
morning.

Current forecast remains on track.

&&

.SHORT TERM /THROUGH THIS AFTERNOON/...
Issued at 312 PM EDT Fri Jun 7 2024

Tonight, the surface high will be focused just south of us moving
toward eastern Tennessee. As a result, there will be mostly clear
skies and dry conditions. After a breezy afternoon, the winds will
become more light and variable overnight as the high pressure shifts
eastward. Temperatures will lower into the mid to upper 50s. Close
to sunrise, convective cloud debris from the decaying MCS over
Missouri will filter over our area. By sunrise tomorrow, expect
increasing mid- and high-level cloud cover.

For tomorrow, low rain chances will spread eastward as the remnants
of the overnight MCS continue to dissipate. NBM is very bullish on
precip chances tomorrow, but given high res model soundings showing
very dry air in the lowest 3km, have decided to back off on PoPs
slightly. Decided to lower PoPs to 20-30% with the highest chances
north of I-64. We can expect some scattered showers tomorrow
afternoon over southern IN, and isolated showers for the rest of KY.
With increasing cloud cover throughout the day, little to no
instability is expected, so thunderstorm chances remain low.
Temperatures for tomorrow will range from mid to upper 70s for
southern IN, and upper 70s to low 80s elsewhere.

&&

.LONG TERM /TONIGHT THROUGH FRIDAY/...
Issued at 312 PM EDT Fri Jun 7 2024

Saturday Night through Monday Night...

Saturday night will feature a cold front slipping in from the
northwest and then slowing down in southern KY by dawn Sunday.
Nocturnal low-level jet will be in play, but not anywhere as strong
as what we saw Friday night.  PWATs will be in the 1.75-1.9 inch
range along that front so primo juice will be available for
convection.  Overall convective evolution here is still a bit
muddled as the HRRR has some sort of MCS rolling through the central
part of our CWA while the 3KNAM, Euro and GFS have an MCS rolling
through mainly southwest and far western KY.  For now, will keep
higher end chance PoPs going for the overnight until we get a bit
more forecast convergence within the next few model cycles.  Overall
severe threat looks pretty low here, but if we get a forward
propagating MCS, then gusty winds and torrential rainfall would be
the main threats.  PoPs should continue into Sunday morning with
drier conditions likely in the wake for the afternoon/evening.
Overnight lows will be in the mid-upper 60s.  Highs Sunday will
likely be in the upper 70s to around 80.  Sunday night lows will be
cooler behind the front with lows in the upper 50s.  Dry and less
humid conditions are expected for Monday and Monday night with highs
in the upper 70s to around 80 and overnight lows in the low-mid 50s.

Tuesday through Friday...

Moving into next week, the pattern will start off with a trough axis
along the east coast with some upper ridging over the Ohio Valley.
This trough axis will move east and the flow over the Ohio Valley
will remain in a west-northwest type pattern.  Earlier forecasts
showed a mid-level perturbation working through around midweek.
However, latest ensembles and deterministic runs have shifted this
feature more to the south and west here.  Additionally the GFS and
its ensembles have reversed course here and are now much more dry
through the period, which matches the Euro.  Perhaps the next chance
of precipitation may arrive in the Thu/Fri time frame as a stronger
wave in the northern stream pushes through the Great Lakes which may
bring at least some iso-sct showers/storms to the region.

Temps will remain below normal for Tuesday with highs in the upper
70s to near 80.  Lower 80s look likely for Wednesday.  An uptick in
temps looks likely for Thursday as highs will warm into the middle
80s.  Latest blend is suggesting upper 80s and lower 90s by Friday.
That seems a bit aggressive given the relative moist soil conditions
and lush vegetation across the region.  More than likely, highs will
top out in the mid-upper 80s by late week and into next weekend.

&&

.AVIATION /06Z TAFS THROUGH 12Z SUNDAY/...
Issued at 141 AM EDT Sat Jun 8 2024

High clouds from a convective system over the central Plains will
begin to move across the region over the next few hours, with winds
remaining light and generally out of the SW through sunrise. Later
this morning, the remnants of the convective system are expected to
move across the region as a weakening band of light rain showers.
Little to no impacts are expected from these showers, and due to
coverage and timing uncertainty, we`ll only go with VCSH mention for
now.

A light SW breeze should pick up after sunrise this morning,
with wind speeds of 5-10 kt expected through the daytime hours
today. Cloud bases will gradually build downward through the day,
though there is high confidence in VFR conditions continuing through
at least the late evening hours tonight. Toward the end of the
current forecast period, a cold front dropping in from the north
will bring an increase of moisture below 10 kft. At this time, we`ll
keep VFR CIGs going through the forecast, although the probability
of MVFR or lower CIGs will increase between 06-12Z Sunday.
Additionally, a second round of rain (and possibly a few storms) may
impact sites early Sunday morning; however, confidence is too low to
mention in the current forecast.

&&

.LMK WATCHES/WARNINGS/ADVISORIES...
KY...None.
IN...None.

&&

$$

UPDATE...SRM
SHORT TERM...CJP
LONG TERM...MJ
AVIATION...CSG