978
FXUS63 KJKL 301853
AFDJKL

AREA FORECAST DISCUSSION
National Weather Service Jackson KY
253 PM EDT Sun Jun 30 2024

.KEY MESSAGES...

- A cold front with showers and thunderstorms will exit southeast
  of the area this evening. A few storms this afternoon could
  produce strong wind gusts and small hail.

- A short-lived break from the heat and humidity is forecast
  tonight through Monday night behind the cold front, quickly
  followed by a return of sultry conditions mid to late week.

- An active period of showers and thunderstorms may occur
  Wednesday through Friday. The greatest probability for showers
  and thunderstorms appears to be on Thursday, Independence Day.
  Heat indices will return to near 100 degrees for many locations
  during this time.

&&

.UPDATE...
Issued at 1133 AM EDT SUN JUN 30 2024

The late morning update is out with minimal changes overall. The
initial cold front has pushed south of Interstate 64, but this is
primarily just a wind shift, with dew points remaining in the
lower to middle 70s even after frontal passage. Lower dew points
and thus increasingly stable air are just entering northern
Kentucky near Covington and will reach and pass the area late this
afternoon through the evening.

UPDATE Issued at 818 AM EDT SUN JUN 30 2024

Precip is more plentiful than anticipated near the TN border early
this morning, and the POP was raised there for this morning.

&&

.SHORT TERM...(Today through Monday)
Issued at 559 AM EDT SUN JUN 30 2024

A cold front is entering KY from the northwest early this morning,
supported by an upper level trough over the Great Lakes headed
east toward New England. Warm/moist advection ahead of the front
has been helping to keep slightly elevated convection firing
through the night. As heating occurs today, convection will become
surface based and further increase in coverage ahead of the
front. With the front moving through the forecast area during the
day, this will place the highest POP in south central and
southeast KY where the front arrives latest. Shear will be rather
negligible, but a fair amount of instability could give some brief
strong storms. The last of the thunderstorms will end in
southeast KY late today or this evening.

Cooler and drier air will move in behind the front, with a
noticeable change in air mass area wide by Monday morning. Most
places are not expected to have temperatures get out of the 70s on
Monday, and this will be accompanied by dew points dropping to
comfortable levels in the upper 40s to mid 50s.

.LONG TERM...(Tuesday through Sunday)
Issued at 253 PM EDT SUN JUN 30 2024

Models continue to be in good agreement with main synoptic
feature and pattern through the extended. At times, a moderately
amplified but progressive flow with generally weak to moderate
wind fields shout out a continuation of our summer time conditions
through the period. Ridging over the eastern CONUS gradually
breaks down as shortwave energy carves off the top through the
first 24-48 hours of the extended. Thereafter, flow aloft takes on
a more zonal flavor with an occasional passing short wave or
minor trough. At the surface, New England high pressure will drift
out into the Atlantic, allowing a frontal zone to develop across
the Midwest. A series of weak surface waves will track through the
Great Lakes along this baroclinic zone, effectively dropping and
lifting a frontal boundary southward and northward in response to
each passing wave of low pressure. With the zonal pattern aloft
keeping the steering flow generally west to east, the boundary
gradually drifts southward but never quite makes it through our
area until possibly at the very end of the forecast window.

After a seasonably warm (highs in the mid to upper 80s) and
relatively comfortable (surface Tds in the upper 50s to lower 60s)
start to the extended on Tuesday, our sensible weather will
generally be warm and muggy through the remainder of the period
under a very typical summer like pattern. With a frontal zone to
our north through a good part of the extended, and an occasionally
passing disturbance aloft, we should expect to see a chance for
showers and thunderstorms just about every day. However, with the
lack of strong ridging over the region and flow generally more
from out of the Deep South, temperatures will be much more typical
of this time of the year, or 80s versus the 90s experienced over
the past couple or few weeks. This will result in a bit lower heat
indices through the period as well, with peaks averaging in the
90s versus around 100 degrees or higher. Surface dew points in the
upper 60s to mid 70s will still make for some typically sticky
summer like weather.

Not seeing much in the way of hazards through the period. There
will be at least a climatologically low 20-30% or higher PoP each
day through the period. The best chance for rain and possibly more
organized convection will be during those period of time that the
frontal zone manages to dip southward, close enough to eastern
Kentucky to fire off convection, first Thursday...possibly into
Friday, and then again Saturday. Overall rainfall totals will be
localized with the hit and miss type convection we typically see
in the summer time. On average, QPF forecasts are not that
impressive, with ensemble probabilistic 24 hour averages showing
only a 25-35 percent chance of a half inch or more of rainfall
during any 24 hour period. Rest assured though, PWATs will be high
enough (~90th percentile of climatology) for some localized heavy
rainfall with any passing thunderstorms. Freezing levels will be
quite high (15-16 kft) and with relatively weak wind fields, mean
storm motions will be at or less than 10-15 kts through the
period. Consequently, any thunderstorms will be capable of
producing locally heavy rainfall.

&&

.AVIATION...(For the 18Z TAFS through 18Z Monday afternoon)
ISSUED AT 143 PM EDT SUN JUN 30 2024

Showers and thunderstorms will impact, or continue to impact all
but KSYM, with this activity clearing the TAF sites by 23z this
evening. This activity will bring sub-VFR conditions at times, and
possibly some gusty and erratic winds under the stronger storms.

Behind the cold front, VFR conditions are expected through the
night and into Monday morning in all but the most sheltered
deeper valleys as dry air moves into the region. At this time, fog
is not expected to significantly impact TAF sites.

VFR conditions are expected Monday morning through early
afternoon, though it should be noted that there is some chance at
low stratus clouds moving into the area from the northeast Monday
morning, which may persist until burning off. There is too low
confidence to mention in the TAFs at this time, and would
primarily impact KSJS and possibly KJKL if it occurred.

&&

.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE...CMC
SHORT TERM...HAL
LONG TERM...RAY
AVIATION...CMC