603
FXUS63 KLMK 091904
AFDLMK

Area Forecast Discussion
National Weather Service Louisville KY
304 PM EDT Thu May 9 2024

.KEY MESSAGES...

*   Very isolated shower or storm possible this afternoon and
    evening, mainly north of I-64. Brief gusty winds and small hail
    are possible.

*   Widely scattered storms possible north through east of
    Louisville Saturday afternoon.

*   Active pattern next week with daily chances of showers and
    storms Monday through Thursday. Severe weather is not expected
    through at least Tuesday. Strong storm chances may increase
    slightly by Wednesday-Thursday, but confidence is low.

&&

.SHORT TERM /THROUGH FRIDAY/...
Issued at 303 PM EDT Thu May 9 2024

A mid/upper level trough continues to drop southeast from the Upper
Midwest, with a mid-level speed max streaming east from Missouri
across the Ohio Valley this afternoon and evening. Sfc low pressure
will continue to move east-southeast across central IN and southern
OH this afternoon, dragging a cold front through the region. There
is still some low-level moisture available with sfc dewpoints still
in the mid 60s. Temperatures have struggled today beneath stratus,
however readings are quickly rebounding into the mid 70s as the low
clouds scatter out from west to east. Temperatures are still likely
to top out in the upper 70s to near 80 degrees by mid-afternoon.

The nearby sfc low and approaching cold front will provide modest
lift as the airmass destabilizes. Much of the precip will remain on
the cool side of the system, closer to I-70 and north. However, a
few isolated cells could develop across southern IN and northern KY.
There is some mid-level warm air to overcome still, as seen on
recent SDF ACARS soundings, and coverage will remain quite sparse.
Mainly dry weather is anticipated, but a few isolated showers and
storms will be possible north of I-64 into the evening hours. With
steeper low-level lapse rates and a dryer column, an isolated storm
or two could produce localized gusty winds. Effective bulk shear of
50+ kts is also more than sufficient for some organization, so there
may be very brief window for small to marginally severe hail.
However, confidence in a stronger storm is low due to very limited
coverage.

Tonight looks fairly quiet with mainly dry weather continuing. A
secondary sfc trough will drop south through the area into Friday
morning. Winds veer northerly in its wake, with a more notable surge
of cooler air. Stratus will blanket the region from north to south
early Friday morning, and cannot rule out a stray light shower or
sprinkle. Clouds will linger into the afternoon hours before partial
clearing late in the day. Highs will only reach the mid to upper 60s
in most places with a brisk north wind. A few spots will top out
near 70 F.

&&

.LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/...
Issued at 303 PM EDT Thu May 9 2024

Stacked low pressure crossing the Great Lakes will swing a cold
front through the Ohio Valley around mid-day Saturday. Soundings
show a strong mid-level cap and very little moisture, so will keep
PoPs low and restricted to areas east of I-65 that will be ahead of
the front in the afternoon. There is a bit of instability below the
cap and the mercury should rise a few degrees above convective
temperatures so will include mention of thunder.

Sunday is still looking good as a small bubble of high pressure
crosses the Tennessee Valley. After a cool start in the mid 40s to
around 50, under mostly sunny skies temperatures will peak in the
70s in the afternoon, right at normal values for this time of year.

An active pattern develops next week with a 5H trough moving through
the region Tuesday and a stronger trough coming in from the west
late week. The Gulf will open up early in the week, allowing enough
moisture to include showery precipitation in the forecast. CAPE and
shear are weak Monday and Tuesday, so severe weather is not
expected, but there`s enough instability to include mention of
thunder.

Confidence is very low by mid/late week, but the general idea is for
an increase in moisture and instability, with shower and
thunderstorm chances ahead of an approaching Plains upper trough.
The main threats for severe weather look to be from the southern
Plains through the Southeast, but there are indications of a slight
uptick in strong storm chances in the Ohio and Tennessee Valleys by
Wednesday or Thursday.

High temperatures next week will primarily be in the 70s.

&&

.AVIATION /18Z TAFS THROUGH 00Z SATURDAY/...
Issued at 206 PM EDT Thu May 9 2024

A sfc low over central Indiana will move ESE across southern OH this
afternoon and evening, dragging a cold front southeast through the
area. BKN MVFR stratus is in the process of scattering and lift from
SW to NE as drier air begins to filter in from the west.
Southwesterly sfc winds will gust to 20-25 kts through sunset, with
winds veering westerly and gradually diminishing 00-06z Fri.

Isolated convection will be possible this afternoon and evening,
mainly north of I-64. However, coverage will be much too low and
likely too far north to consider any TSRA mention in the SDF and LEX
TAFs.

A second sfc trough is forecast to drop south through the area
overnight into Friday morning, with cooler air and winds veering
northerly in its wake. MVFR stratus is likely to overspread the
region from north to south early Friday morning.

&&

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

&&

$$

SHORT TERM...EBW
LONG TERM...13
AVIATION...EBW