429
FXUS63 KLMK 201057
AFDLMK

Area Forecast Discussion
National Weather Service Louisville KY
657 AM EDT Fri Sep 20 2024

.KEY MESSAGES...

*  Mainly dry and hot weather through Sunday with highs each day
    near or above 90 degrees. Patchy fog possible this morning.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 311 AM EDT Fri Sep 20 2024

Upper ridge axis from Texas to Lake Huron remains in control of our
weather, so look for another dry and hot day. Low-level thickness
progs suggest max temps close to persistence, perhaps a degree
warmer than Thursday. Even with dewpoints remaining low enough to
keep heat index values in line with the actual air temperature, most
locations will reach the lower 90s, which is well above normal for
this time of year.

Light return flow and even the start of some moisture pooling over
southern Indiana tonight will continue the warming trend for
nighttime temps, with Saturday morning lows closer to midsummer
normals for most.

&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...
Issued at 311 AM EDT Fri Sep 20 2024

===== Saturday - Sunday Night =====

A weak frontal boundary will be stretching across the region
Saturday morning, which could bring a few sprinkles or very light
showers to some portions of the region. Overall moisture associated
with the boundary will be lacking, so we certainly won`t get any
relief from the dry or drought conditions from Saturday`s sfc
boundary. Best chances for any light precip will be mainly north of
the Western Kentucky/Bluegrass Pkwys, but chances will remain below
15% for now.

Otherwise, hot and mostly dry conditions will remain for the
weekend, largely thanks to strong upper ridging extending across
much of the central US. Majority of our forecast area remains in a
D1 Moderate Drought, though the latest US Drought Monitor (updated
yesterday) expanded D2 Severe Drought conditions as well.
Temperatures for Saturday will once again be in the upper 80s and
low 90s. However, sfc dewpoints will mainly be in the 60s, which
will help keep heat indices from creeping into the triple digits.
The warm conditions continue for Saturday night as well, with above
normal temperatures expected for most areas. Generally expecting 60s
overnight, though temps will be on the cooler side along and east of
I-75.

An upper shortwave over the western US will be pivoting into the
Central US on Sunday, which will help motivate the upper ridge to
eventually push east. The upper ridge axis should eventually slide
east of our area sometime on Sunday, which will open the door for
temperatures to finally cool down, but also bring rain chances back
into the forecast.

PoPs will begin to filter in from the NW on Sunday, ahead of the
upper wave and an associated sfc cold front. Some isolated to
scattered showers and storms will be possible on Sunday, mainly for
our northwestern half of the CWA, as outlined in the SPC Day 3.
Sunday will also be the last day for any chance of 90 degree
temperatures for the next several days. With increasing clouds and
rain chances greatest across southern Indiana, they could end up
remaining in the 80s, with warmer temperatures to the south and
east.


===== Monday - Thursday =====

The upper ridge will continue to slide to the east for the first
half of next week. Rain chances really ramp up for the Monday-
Tuesday time frame as a sfc low and associated cold front pass
through the area. Certainly appears to be a good chance for
scattered showers and storms for at least those two days, and
lingering lower chances for the mid-week as the front takes it`s
time progressing eastward. We`ll definitely take any rain chances we
can get at this point. Temperatures will also be quite lower for
next week, with highs still in the 80s for Monday as we should
still be pre-frontal, but upper 70s and low 80s for Tuesday through
the end of the week.

&&

.AVIATION /12Z TAFS THROUGH 18Z SATURDAY/...
Issued at 656 AM EDT Fri Sep 20 2024

VFR conditions expected through the valid TAF period. Look for a few
high-based diurnal Cu, and winds settling into a WSW direction by
late morning, with speeds remaining below 10 kt. Should decouple
shortly after sunset, but with a fairly dry air mass, no
restrictions to vis are expected overnight.

&&

.LMK WATCHES/WARNINGS/ADVISORIES...
KY...Air Quality Alert until midnight EDT tonight for KYZ029>031.
IN...Air Quality Alert until midnight EDT tonight for INZ077>079-
     090>092.

&&

$$

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