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000
FXUS63 KLMK 231741
AFDLMK

Area Forecast Discussion
National Weather Service Louisville KY
141 PM EDT Tue Apr 23 2024

.KEY MESSAGES...

*   Southwest winds will gust 25-35 mph today, especially this
    afternoon.

*   The gusty winds combined with filtered sunshine and temperatures
    rising into the lower and middle 70s may lead to slightly
    increased fire danger this afternoon in exposed areas where
    fuels can lose moisture.

*   Light rain showers this evening and tonight, especially along
    and north of I-64.

*   Lows in the 30s Wednesday night from southern Indiana into the
    northern Bluegrass region, and typical cold spots.

*   Active weather Friday through the weekend, but plenty of
    uncertainty in timing of any intervals of showers and
    thunderstorms.

*   Weekend will feature temperatures in the 80s and breezy
    southerly winds.

&&

.SHORT TERM /THROUGH WEDNESDAY/...
Issued at 303 AM EDT Tue Apr 23 2024

Southwest winds between low pressure over the Great Lakes and high
pressure over Georgia and South Carolina, combined with sunshine
filtered through high clouds, will bring us a warm and breezy spring
day today. Winds gusting 25-35mph this afternoon will help to push
temperatures into the lower and middle 70s.

The low to our north will advance along the St Lawrence River
tonight and drag its trailing cold front through the Ohio Valley.
The front will be weakening as it passes through and will have only
a narrow band of moderately enhanced atmospheric moisture pooling
along it, mostly in the mid and upper levels. Instability continues
to look meager. So, a band of showers, mostly light, is expected to
enter southern Indiana from the north by early evening and proceed
southeastward across central Kentucky tonight, ending by the time
the sun comes up tomorrow morning. General rainfall amounts over
southern Indiana around a quarter to a third of an inch will
diminish to less than a tenth of an inch in southern Kentucky.

Despite the cold frontal passage, low temperatures by dawn will only
fall to the upper 40s in southern Indiana and to the mid 50s in
southern Kentucky, with colder air well behind the front over the
upper Great Lakes closer to a dome of Canadian high pressure over
Ontario.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
Issued at 303 AM EDT Tue Apr 23 2024

===== Wednesday - Thursday =====

Dry weather is expected for our Wednesday and Thursday as sfc high
pressure slides across the Great Lakes. Temperatures will be near
normal for this time of year, with highs on both days on either side
of 70F. For areas north of the Ohio River and in the Bluegrass
region, temps could perhaps be a few degrees cooler where cloud
cover may linger into the afternoon peak heating hours. Wednesday
night and into Thursday morning should be a decent radiative cooling
night, with clear skies and light winds. Temps will range from upper
30s across the Bluegrass region to the mid 40s across south-central
Kentucky. Some of our traditional cool spots may underachieve
forecast lows, so maybe another opportunity for some isolated frost
development in the Bluegrass.


===== Friday - Weekend =====

While the mid-week will be quiet in the Ohio Valley, the upper flow
transitions across the southwestern US as an upper low deepens and
pivots towards the Plains. Deep southwesterly flow will take over by
Thursday night, resulting in mild temps for Friday morning. Warming
trend will continue for Friday and into the weekend, with temps
warming to the low-mid 70s on Friday, and temps surging into the 80s
for Saturday and Sunday.


Precip Discussion... As for precip chances, we`ll see PoPs make a
return to the forecast by Friday morning. The aforementioned upper
low will likely be located east of the Rockies by Friday morning,
with a cold front stretching to the south into Texas, and a warm
front extending out to the east and into the Tennessee Valley. This
warm front boundary will push northward during Friday, bringing
increased rain chances and isolated thunder to our area. Highest
PoPs of Friday will be during the daytime hours. Model soundings are
not too impressed with instability profiles, though the shear will
likely increase later in the day as a broad LLJ expands into the
lower Ohio Valley as the upper low spins towards the Great Lakes
region.

We`ll remain in the warm sector of the low pressure system through
the weekend, with some mid-level vorticity lobes swinging around the
parent upper low to provide additional forcing. This will likely
lead to additional on and off rain chances through the weekend.
Still don`t have much confidence on timing each little disturbance,
so will keep a broad brush PoP going for majority of the weekend. If
there`s any area that has the best chance of being mostly dry this
weekend, it`ll be the Lake Cumberland region.


Wind Discussion... A breezy period is expected for Friday and into
the weekend as southerly sfc winds ramp up. To start things off,
we`ll likely see wind obs increase by the Friday afternoon hours as
the LLJ expands eastward and the sfc pressure gradient tightens. Sfc
winds will continue to ramp up for Saturday and Sunday as the
pressure gradient remains in place, with each afternoon having high
probabilities of wind gusts greater than 30 mph. For Saturday
afternoon, roughly 80-90% of EPS members suggest wind gusts greater
than 30 mph will be concentrated from Lexington and I-75 and
pointing westward. For Sunday afternoon, between 70-85% of EPS
members indicate wind gusts greater than 30 mph for the same areas.
Probabilities for gusts greater than 40 mph fall below 40% at this
time, but it`s worth keeping an eye on in the coming days.


==== Early Next Week =====

Another upper low system for early next week looks to follow a
similar track as the late week system discussed above. This will
likely bring shower and storms to the region for Monday. As of now,
model soundings don`t show much sfc-based instability, but will keep
tabs on the trends throughout the coming days.

&&

.AVIATION /18Z TAFS THROUGH 00Z THURSDAY/...
Issued at 141 PM EDT Tue Apr 23 2024

Breezy SW winds this afternoon with gusts frequently around 25 kt.
Precip associated with the cold front arrives in HNB around 23Z,
then SDF and LEX in the 01-03Z time frame, but cig/vis should only
dip into the higher end of MVFR, if not remain VFR. Winds veer to
due west and diminish as the gradient is weaker near the front.

Rain departs shortly after midnight, with any low clouds scattering
out by Wed morning. Lighter winds out of the NNW on Wednesday, with
speeds remaining near or below 10 kt as high pressure builds in.

&&

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

&&

$$

SHORT TERM...13
LONG TERM...CJP
AVIATION...RAS