293
FXUS63 KJKL 121427
AFDJKL

AREA FORECAST DISCUSSION
National Weather Service Jackson KY
1027 AM EDT Fri Jul 12 2024

.KEY MESSAGES...

- Hotter conditions make a comeback through this week and into
  next week, with heat indices peaking around 100 degrees Monday
  through Wednesday.

- The next significant chance of rain arrives toward the middle
  of next week.

&&

.UPDATE...
Issued at 1026 AM EDT FRI JUL 12 2024

Very very little changes made to the grids aside from loading in
the latest surface obs and adjusting those trends through the
remainder of the morning. The biggest change made was updating
morning text and radio products to remove mention of fog. Grids
have been saved and sent.

UPDATE Issued at 705 AM EDT FRI JUL 12 2024

There are no significant changes with the morning update. While
the grids will be updated to be initialized with the latest
observations, the text products will not be refreshed.

&&

.SHORT TERM...(Today through Saturday)
Issued at 325 AM EDT FRI JUL 12 2024

An upper trough remains situated from the Great Lakes with trough
axis extending south-southwest to the Mid-Mississippi and lower Ohio
River Valleys early this morning. A weak mid-level disturbance
continues to trigger scattered showers across the eastern Bluegrass
region this morning, but most areas in eastern Kentucky are, and
will remain, dry.

The aforementioned upper trough dampens significantly and lifts out
of the Great Lakes region, with gradual mid-level height rises
through Saturday despite weak disturbances brushing/grazing the area
from the northwest. The best chances for rain will thus be this
morning through the afternoon over the northwestern Bluegrass region
and then again Saturday afternoon as the next weak system brushes
the region and allows for an increase in instability. However,
outside of rain chances early this morning, the PoPs were left below
the 15 threshold which is needed for a mention in the official
forecast, so for now the entire short-term period will be left dry
across eastern Kentucky.

With gradual height rises and a slight decrease in moisture by late
afternoon, expect high temperatures to rise a few more degrees from
Thursday with upper 80s to lower 90s expected under partly cloudy
skies. Lows tonight will also rise a couple of degrees with lows in
the 60s compared to this morning, with lower 60s in the typically
coolest sheltered valleys. Saturday`s highs in the lower 90s with
isolated pockets of mid-90s seem reasonable with a slight uptick in
instability yet still remaining fairly dry.

.LONG TERM...(Saturday night through Thursday)
Issued at 349 AM EDT FRI JUL 12 2024

The latest 12/00z model suite upper level analysis beginning
Saturday evening shows Kentucky amidst weak troughing between an
~598 dam high centered over the Central Rockies and another ~598 dam
high over the Western Atlantic. At the surface, weak high pressure
is spatially displaced east of former covering the Ohio Valley
and portions of adjacent regions. Over the upcoming weekend, the
upper level high to our west will gradually weaken while
elongating eastward toward the Commonwealth, briefly becoming more
amorphous. Meanwhile, the corresponding surface high retreats
southward to near the Gulf Coast by Sunday night where it will
begin to merge with a stronger surface high over the Atlantic. Far
to the north, reinforcing shortwave energy will phase southwest
of the Hudson Bay, causing an upper level trough to dig into the
Great Lakes/Ohio Valley on Tuesday/Wednesday and lingering there
through Thursday. This will will be reflected at the surface by a
cold front approaching the Ohio River from the northwest late
Tuesday and passing on Wednesday/Wednesday night. However, that
front likely struggles to push beyond the spine of the Southern
Appalachians and instead stalls just to our south and east on
Thursday as Canadian high pressure builds over the Great Lakes.

Before that cold front arrives, the heat and humidity will
gradually increase each day as 850 mb temperatures climb to around
22-23C by Monday/Tuesday, as per CMC/GEFS/EFS. This will stoke
some of the hottest if not the hottest temperatures of the year
thus far come Monday and Tuesday, barring substantial deep
convection during the period of peak heating. At this point, there
appears to be a low end threat for showers and thunderstorms on
Sunday afternoon and evening with a passing disturbance. Subtle
shortwave ridging aloft, should preclude most convection on
Monday. Rain chances then return on Tuesday as heights begin to
fall ahead of the upper level trough/cold front. Rain
probabilities peak on Wednesday (60 to 70% chance). Thereafter,
the better rain chances become increasingly focused near and
south of the Hal Rogers Parkway/ Highway 80 corridor by Thursday
as the cold front stalls out along the Southern Appalachians.
Temperature-wise, look for highs mainly in the lower 90s on
Sunday, before climbing into the mid 90s for many locations on
Monday and Tuesday. At this point, Monday is forecast to be the
sunniest and hottest day. In fact, Jackson`s record high of 95 set
in 1988/1995 and London`s record high of 95 set 1988 both stand
in danger of being tied or perhaps even broken. On Tuesday, higher
moisture levels and greater cloud cover should keep highs a
degree or two cooler than Monday. Even so, the higher dew points
will keep maximum apparent heat indices similar to Monday,
generally close to 100F. High temperatures finally retreat back
to seasonable levels the mid 80s behind the front on Thursday.

&&

.AVIATION...(For the 12Z TAFS through 12Z Saturday morning)
ISSUED AT 708 AM EDT FRI JUL 12 2024

The period will remain mostly VFR across eastern Kentucky outside
of some lingering morning fog/mist to begin the period at KSME.
Expect another day of FEW to SCT afternoon cumulus development
generally with cloud bases once again in the 5 kft to 6 kft range.
Winds will remain light and variable through the period. MVFR
fog/mist was indicated in the TAFs at both KLOZ and KSME late in
the TAF period, with low confidence in both severity and timing at
this time.

&&

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

$$

UPDATE...VORST
SHORT TERM...CMC
LONG TERM...GEERTSON
AVIATION...CMC