038
FXUS63 KLMK 281739
AFDLMK

Area Forecast Discussion
National Weather Service Louisville KY
139 PM EDT Tue May 28 2024

...Updated Aviation Discussion...

.KEY MESSAGES...

*   Dry weather and below normal temperatures expected for most of
    the upcoming week.

*   Rain chances return for the weekend; severe weather is not
    expected at this time.

&&

.UPDATE...
Issued at 138 PM EDT Tue May 28 2024

Quiet conditions prevail this morning as surface high pressure
overspreads the region. Expect winds to pick up later this morning as
an approaching shortwave tightens up the pressure gradient resulting
in WNW winds gusting around 20-25mph at times through sunset. Some
of the latest CAM guidance does suggest isolated pop up shower
potential this afternoon, but meager moisture availability and
instability, combined with a notable warm layer between 750 and
700mb, should limit any development this afternoon. Will continue
with silent PoPs for the morning update.

Will continue monitoring an area of convection over southern MN and
northern IA associated with a surface low centered near Milwaukee,
WI as it makes its projected journey southeastward across IL and
IN. Some models suggest weakening showers could make it into our
southern Indiana counties late tonight, but aforementioned limiting
factors may likely preclude this solution.

Only notable update to the going forecast was to increase wind
speeds a tad across southern Indiana through today; otherwise, only
blended near term grids with local observations to better reflect
reality. Updated products forthcoming.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 315 AM EDT Tue May 28 2024

Cool and quiet start to the morning with only some patchy fog
anticipated in the more usual fog-prone locations. Light but steady
southwesterly winds have kept the fog from becoming a bigger issue
despite the clear skies and saturated soils from recent rains.

Plenty of sunshine is expected today as dry air funnels in from the
west and northwest and weak high pressure over the Plains slowly
drifts toward us. A cu-field will likely develop by late morning or
early afternoon as the boundary layer mixes out, though capping near
750mb will hamper vertical cloud growth. It`s not until late in the
day that we see the cap nearly erode across northern portions of the
region ahead of a weak frontal boundary, and some CAMs indicate very
isolated convection is a possibility with the eroding cap. For the
current forecast package, plan to run with ~10% PoPs across our
northeastern zones for the late afternoon and early evening hours.

Overnight, any remaining isolated showers should gradually diminish
in coverage as low level CIN increases. Slightly cooler/drier air
will filter in behind a weak frontal boundary.

&&

.LONG TERM /WEDNESDAY THROUGH MONDAY/...
Issued at 315 AM EDT Tue May 28 2024

Wednesday - Thursday...

Large scale upper level troughing lingers over the eastern US and
Canada Wednesday and Thursday. A couple of shortwave troughs will
rotate cyclonically over the Upper Ohio Valley, the first on
Wednesday and the second on Thursday. The first wave on Wednesday
will have a bit more low to mid-level moisture to work with,
although it is still fairly shallow. Deeper moisture will remain off
to our northeast across OH/WV/PA. But with the aid of diurnal
heating, we should see a fairly healthy cumulus field and perhaps a
few showers in the Bluegrass Region. Thunder seems unlikely due to
the very shallow nature of any isolated convection, but cannot
completely rule it out. Most will enjoy a dry, partly sunny day with
highs in the mid 70s.

Narrow upper level ridging over the Plains Wednesday nudges eastward
over the MS Valley by Thursday as sfc high pressure expands
southeast over the Great Lakes. This setup will maintain dry
northerly flow across our region. Wednesday night and Thursday look
very pleasant with lows in the lower 50s and highs in the mid 70s.


Thursday night - Friday...

High pressure at the sfc and aloft will maintain a strong influence
on our local weather through Friday. Sfc high pressure drifts
southeast across the Upper Ohio Valley, with light northeasterly to
easterly low-level flow. The cool NE flow and proximity of the high
will result in a rather cool start to Friday. Expect lows in the mid
40s to lower 50s. Friday looks gorgeous with afternoon highs in the
mid/upper 70s.


Saturday - Monday...

High pressure slides east of the region by the weekend as a weak low
pressure system lifts northeast out of the central Plains.
Strengthening southwesterly flow between the two will advect moist
air back into the Ohio Valley. Increased forcing provided by low-
amplitude shortwave troughs will bring daily rain/thunderstorm
chances back to central KY and southern IN Saturday into early next
week. We can also expect a return to relatively warmer, more humid
conditions with highs in the upper 70s/lower 80s and lows in the
60s.

&&

.AVIATION /18Z TAFS THROUGH 00Z THURSDAY/...
Issued at 138 PM EDT Tue May 28 2024

Expect VFR conditions throughout this TAF cycle. Latest surface
analysis reveals broad high pressure across the OH Valley while
current satellite shows a cumulus field developing behind the cold
front from the east coast into our region. Some hi-res models show
isolated showers possible today, but AMDAR soundings out of SDF
continue to show stable layers aloft and an abundance of dry air
that should limit any showers from developing. Gust winds from the
west will continue through around sunset before backing to WSW and
lightening to less than 7 kt overnight. Low VFR CIG with bases
around 5kft are expecting by tomorrow morning as well as another day
of gusty NW winds.

&&

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

&&

$$

UPDATE...CG
SHORT TERM...DM
LONG TERM...EBW
AVIATION...CG