840
FXUS63 KLMK 190721
AFDLMK

Area Forecast Discussion
National Weather Service Louisville KY
321 AM EDT Fri Jul 19 2024

.KEY MESSAGES...

*   Gradual warm up this weekend with increasing mugginess by early
    next week.

*   Shower and storm chances across southern KY this weekend,
    increasing everywhere early to mid week. Locally heavy rainfall
    possible by early next week.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 321 AM EDT Fri Jul 19 2024

A surface low, sitting under an upper trough extending south through
the eastern Great Lakes and continuing down the Mississippi River
Valley to the Gulf of Mexico, is sliding eastward from the Midwest
into the southern Great Lakes region. This is keeping northeasterly
winds over southern Indiana and central Kentucky light under mostly
clear skies. Dry air continues to get advected over the area,
keeping dew points in the mid to upper 50s.

Later today, clear skies will make for lots of sunshine. Some light
cirrus will become more common as the day wears on, but temperature
should have no problem reaching into the low to mid 80s. Dew points
remain low climbing only into the mid 50s to low 60s, so it`s going
to be another nearly perfect day.

Tonight, winds will once again ease and go near calm, but mid-level
moisture, near the 700mb level, will begin to work northward into
south central Kentucky. This will bring 5-10 k foot ceilings to
those in and around a line from Bowling Green to Lexington and to
the southeast of that line. After around midnight, a 20-30% chance
of precipitation will develop along the Kentucky/Tennessee border
from near Bowling Green and points to the east. Low dew points
should limit fogging.

&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...
Issued at 321 AM EDT Fri Jul 19 2024

Saturday - Sunday Night...

The Ohio River Valley will remain positioned between two upper
features through the weekend. An anomalous upper low will dig across
eastern Canada, with a secondary cutoff low meandering over the
lower Missouri River Valley. Meanwhile, a strong upper ridge will be
positioned over the western Atlantic. We`ll see a steady feed of
Gulf of Mexico moisture across the SE CONUS between these two
features, with the northern fringes of the PWAT plume across
southern and eastern KY. Farther north across southern IN and
northern KY, a much drier airmass is expected (PWATs around 1",
rather than 1.75" down south). Given the relative lack of moisture,
and the upper trough axis displaced too far to the NW, expect the
northern half of the CWA to stay dry. Will continue chance pops
across the south, generally along and south of the Parkways through
early Sunday evening. Better moisture arrives by Sunday night, and
will have some small chances across the whole CWA by then.

Slower moving heavy rainers will be the main concern with any shower
or storm across our south through the weekend. We do stay on the
northern fringes of the PWAT plume, so the highest values and best
coverage will likely remain to the south and east of the CWA, but
still can`t rule out some locally heavy amounts.

Overall, temperatures will stay pretty near normal with values
mostly in the mid to upper 80s. A few locations could touch 90 by
Sunday. Look for lows in the low and mid 60s on Saturday night, and
a little milder by Sunday night as the deeper moisture arrives. 65
to 70 degree readings expected by Sundrise Monday morning.

Monday - Thursday...

The same upper pattern still holds going into the early and mid week
time frame, although the upper trough axis will be impinging a bit
more into our region. This combined with the continued deep moist
plume advecting around the NW periphery of the upper ridge, and the
broad baroclinic zone from the western Gulf Coast states up through
the mid Atlantic will be enough to allow for rounds of showers and
thunderstorms. Will carry chances through the entire week, with the
best coverage still across the southern and eastern portions of the
CWA. PWATs are expected to jump above 2" through the column with
certain waves (most likely Monday and Tuesday), and give relative
slow and rougly parallel movement to the surface boundary, locally
heavy rain is possible. Given the prolonged nature of this pattern,
am a bit concerned about some localized flash flooding. This will be
more likely SE of the CWA, but we could get in the game with
repeated rounds. Look for slightly below normal temps in the low to
mid 80s.

&&

.AVIATION /06Z TAFS THROUGH 12Z SATURDAY/...
Issued at 212 AM EDT Fri Jul 19 2024

With high pressure over the region, VFR conditions are expected
through the forecast period. Winds will remain light and generally
out of the northeast. Skies will begin mostly clear, but the region
will likely see more cirrus streaming overhead later in the period.

&&

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

&&

$$

SHORT TERM...KDW
LONG TERM...BJS
AVIATION...KDW