060
FXUS63 KJKL 161945
AFDJKL

AREA FORECAST DISCUSSION
National Weather Service Jackson KY
345 PM EDT Tue Jul 16 2024

.KEY MESSAGES...

- Hot and humid weather will bring heat index values ranging from
  the upper 90s to the lower 100s to many locations Tuesday.

- Showers and thunderstorms will impact the region late this
  afternoon through early next week.

- Thunderstorms this afternoon into the overnight will be capable
  of producing damaging wind gusts. There is also the risk for
  excessive rainfall through Wednesday from potentially repeat
  rounds of showers and thunderstorms, despite antecedent
  abnormally dry conditions for many areas.

- A welcomed relief from the heat follows for Thursday through
  early next week, with afternoon high temperatures in the upper
  70s to lower 80s.


&&

.UPDATE...
Issued at 230 PM EDT TUE JUL 16 2024

Capping has been keeping a lid on convection thus far early this
afternoon. This should change in the next few hours. Will
maintain isolated to chance PoPs area-wide. The rest of the
forecast generally remains on track.

UPDATE Issued at 1151 AM EDT TUE JUL 16 2024

The forecast remains on track late this morning. Some isolated
convection attempted to initiate earlier in response to
progressive outflow that moved through from the northwest, but
this was fairly short-lived in nature. The more organized
activity has since settled across the terrain in northern
Tennessee, with only a few echoes popping up in southeastern
Kentucky thus far. The latest CAM guidance continues to advocate
for only isolated to scattered PoPs through the majority of the
day, given the lack of shear and weaker forcing at play. As we
head into early this evening, PoPs do increase north of I-64, as
better moisture and wind fields move in across the region. Highs
in the low to mid 90s are on track, although with cumulus already
developing, did tweak a few of the higher numbers down just a bit.
Updates have been sent.

UPDATE Issued at 729 AM EDT TUE JUL 16 2024

Debris clouds from upstream MCS activity overnight has started to
thin and diminish over eastern Kentucky. Have thus gone back and
lowered Sky coverage in the grids significantly from the last
update this morning. This yields higher confidence in achieving
today`s forecast highs in the lower to mid-90s, with associated
heat indices approaching 105 degrees in some of the warmest
locations. Also blended the current PoPs from the morning forecast
package with the latest 1-hr NBM PoPs and then smoothed somewhat
to blend with neighboring forecasts. Also used the latest
observations as the initialization for the update to the grids for
the next several hours.

&&

.SHORT TERM...(Today through Wednesday)
Issued at 331 AM EDT TUE JUL 16 2024

Eastern Kentucky will see an increasingly active weather pattern
through Wednesday afternoon as the area comes under the influence
of increasing cyclonic flow aloft and a cold front approaches
from the northwest.

A large MCS continues to weaken upstream over the Midwest as it
approaches the area. Latest trends suggest little to no rain
reaching the area this morning, with some remnant outflow winds
possibly impacting areas especially north of Interstate 64. But
trends will need to be monitored as what is left of the MCS
approaches the area.

The remnant debris clouds left from the MCS will move over the area
this morning. This may prevent high temperatures today from reaching
their full potential this afternoon. The NBM has trended downward
a degree or two compared to 24 hours ago, but with lower to
mid-90s still expected. Humidity will also increase today as warm
advection continues to push moisture into the region. With the
question mark of cloud cover today and uncertainty with how
quickly dew points rise today, will cover the heat impacts with a
Special Weather Statement as we have been doing.

As for showers and thunderstorms, expect generally low chances until
late this afternoon into the evening as models depict moisture
advection fairly parallel with the mid- and upper-level winds
entering northern parts of the CWA by this evening. This
increases the chances of showers and thunderstorm activity
training across parts of the area, especially toward the
Interstate 64 corridor, which is why the Weather Prediction
Center has issued a Slight Risk for excessive rainfall. However,
given antecedent abnormally dry conditions it will take more rain
than usual to cause any significant flooding issues. Thus, have
decided to withhold any issuance of a Flood Watch at this time.

As disturbances move west to east across the area the approaching
cold front and upper level trough will gradually push shower and
thunderstorm activity south across the CWA through Wednesday.
Widespread categorical PoPs cover the area Wednesday during the
daytime period, which will bring badly needed rainfall for many
areas, though again will need to watch for the potential for
excessive rainfall with a Slight Risk continuing over eastern parts
of the forecast area.

.LONG TERM...(Thursday through Tuesday)
Issued at 345 PM EDT TUE JUL 16 2024

The period will begin much cooler than of late, as there is good
agreement in the ensembles and deterministic guidance that mid-level
ridging breaks down. At the surface, the guidance remains some what
uncertain just how far south the cold front gets, but will still be
much cooler and drier to begin the period from Thursday into Friday.
The uncertainty on the front will affect the far southeast the most,
with fairly low PWATs of only around an inch expected in these areas
that could lead to showers and perhaps a few thunderstorm mainly in
the afternoon and early evening Tuesday and Friday. Outside of
that far southeast areas PWATs will be below 1 inch and will lead
to much drier feel on Friday. The highs will top put in the upper
70s and lower 80s each day and this is about 5 degrees below the
climate normals for this time of year.

The ensembles and deterministic models show some height rises as
we move toward the weekend into early next week. However, it looks
meager as we see a mid-level low push toward the Midwest and the
Ohio Valley looks to get stuck in between these features. Given
this we will continue to see slightly below to near normal
temperatures through the weekend into early next week. We will
also be stuck on the periphery of the ridging and this should
open the door for a slightly more active pattern to possibly lead
to a few bouts of showers and thunderstorms through the period.
Even so, storm total QPF from Saturday into Tuesday is still
around a quarter of an inch in the Bluegrass to around and inch
near the Cumberland Valley. The afternoon highs will also remain
in the low to mid 80s as a result of more unsettled pattern and
cloud cover. Not to mention the 850 mb temperatures flat line in
the around 17 celsius range at best through the remainder of the
period. Right now peak area wide chances of rain will be Tuesday
at around 50-70 percent.

&&

.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)
ISSUED AT 230 PM EDT TUE JUL 16 2024

Generally VFR conditions will prevail through the majority of the
period. Some isolated to scattered convection will be possible
at all terminals through early this evening, before increasing
chances look to become confined more towards the I-64 corridor,
including KSYM. Any direct hit from thunderstorms will bring
temporary MVFR or lower conditions. As a cold front drops
southeast towards the area later tonight into Wednesday, showers
will expand in areal coverage by the pre-dawn hours Wednesday.
Surface winds of 5 to 10 kts out of the southwest to west
southwest will diminish by early this evening.

&&

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

$$

UPDATE...GEOGERIAN
SHORT TERM...CMC
LONG TERM...DJ
AVIATION...GEOGERIAN