281
FXUS63 KLMK 071920
AFDLMK

Area Forecast Discussion
National Weather Service Louisville KY
320 PM EDT Sun Jul 7 2024

.KEY MESSAGES...

*   Hot temperatures return Monday, with slowly increasing humidity.

*   Moisture associated with the remnants of tropical cyclone Beryl
    will move into the Ohio and Tennessee Valleys on Tuesday.
    Isolated strong to severe storms will be possible Tuesday
    afternoon into the overnight hours, with heavy rainfall and
    isolated instances of damaging wind gusts and brief tornadoes
    possible in the strongest storms.

&&

.SHORT TERM /THROUGH MONDAY/...
Issued at 319 PM EDT Sun Jul 7 2024

Sfc high pressure near Toledo will continue to modify tonight and
Monday as it starts to retreat to the NE. Pressure pattern behind
the departing high is too weak for a Gulf moisture tap, but we will
see temps and dewpoints trend a few degrees higher compared to
today. Look for temps 3-4 degrees warmer, and dewpoints increasing
to the mid or upper 60s on Monday. The slightly warmer overnight
temps will keep fog formation at bay tonight. Heat index values
Monday will be in the mid/upper 90s.

Even with the increase in low-level moisture, deep moisture remains
lacking so no mention of precip planned. Can`t rule out a diurnal
pop-up close to the KY/TN border, but that`s less than a mention-
worthy chance.

&&

.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
Issued at 319 PM EDT Sun Jul 7 2024

Monday Night Through Wednesday Night...

A moisture plume ahead of Tropical Cyclone Beryl will begin
advancing toward the region Monday night into Tuesday. The center of
Beryl`s circulation by dawn Tuesday morning will likely be near the
ArkLaTex region, but will steadily advance northeastward through the
day and likely pass just north of the CWA on Wednesday.

Rainfall in our region could begin as early as Monday night, but
will likely hold off until Tuesday. While there are some slight
variations, most model/ensemble consensus peg the heaviest rainfall
to be along an axis stretching from northern Arkansas into
central/northern Indiana. As such, the threat for flooding rains
appears to be low within our CWA, though any heavier shower or storm
that develops in this environment would be capable of torrential
downpours.

Of more concern is the potential for isolated damaging wind gusts
and brief tornadoes within the outer bands of Tropical Cyclone
Beryl. Our region will be within the right-front quadrant of this
tropical system Tuesday, which is the most favorable area for
tornadic showers/storms. Model soundings ahead of the outer bands
that form Tuesday afternoon into the overnight hours show elongated
hodographs with plentiful shear/helicity in the low levels.
Instability will also be present as we heat up and steepen low level
lapse rates ahead of the arrival of the tropical system. Will need
to keep an eye on this setup, as changes in the overall track of
Beryl and/or its speed will play a role in how favorable our
environment will be for tornadic potential.

Depending on Beryl`s track, we could see some gusty gradient winds
Wednesday afternoon, particularly if we get any clearing. EPS
probabilities of +30mph wind gusts are near 70% for most of the
region.

Thursday into the weekend...

Mostly dry and hot weather is expected to return in the wake of
Beryl. Can`t rule out isolated showers/storms at times during this
period, but we`ll lack any sort of defined lifting mechanism to get
convection going, and warmer air aloft associated with upper level
ridging nudging in from the south and west will make it hard to get
any storms going.

&&

.AVIATION /18Z TAFS THROUGH 00Z TUESDAY/...
Issued at 123 PM EDT Sun Jul 7 2024

VFR conditions expected through the valid TAF period. Main
difference going into Monday morning compared to this morning is
temps are not expected to cross over this afternoon`s dewpoints.
Couldn`t rule out brief MVFR vis at HNB or BWG, but not confident
enough to include it in the TAFs.

Wind field is fairly sloppy with the sfc high parked along the
Indiana/Ohio line. Model progs want to back current (mainly) E-NE
winds to north this afternoon, but not seeing much support for that
in the pressure pattern. Will keep it light/variable this afternoon
and tonight, then light SSE on Monday morning.

&&

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

&&

$$

SHORT TERM...RAS
LONG TERM...DM
AVIATION...RAS