856
FXUS63 KJKL 172020
AFDJKL

AREA FORECAST DISCUSSION
National Weather Service Jackson KY
420 PM EDT Mon Jun 17 2024

.KEY MESSAGES...

- Hot weather persists through the week. Afternoon heat indices
  may peak around 100 at some locations.

- The upper level high/ridge bringing our heat wave will weaken
  next weekend and allow a cold front to move into the area,
  possibly bringing thunderstorms.

&&

.SHORT TERM...(This evening through Tuesday night)
Issued at 304 PM EDT MON JUN 17 2024

Current surface analysis has yesterday`s slow moving warm front off
to the east of the area. Surface high pressure is firmly entrenched
across much of the southeastern CONUS. To the north, a shortwave is
moving through the Great Lakes but with the strength of the upper-
level ridge, that feature will remain well north of the area.

For the remainder of the day, near to or record setting temperatures
are forecast to continue to climb into the low to mid-90s with heat
indices pushing 100 degrees. Continued caution and heat safety
awareness should exist as these above average temperatures will
remain in place through the period. Also, increased moisture across
the area will allow for the development of showers and thunderstorms
this afternoon which may linger the evening before dissipating after
sunset. SPC mesoanalysis is pinging the region for SBCAPE values
pushing in the 3,000 J/kg range with PWs approaching 2.00" both of
which could create some decent thunderstorms with heavy rainfall.
Like yesterday, unfavorable severe parameters exist; therefore,
severe thunderstorm chances should be limited. Once showers
dissipate, lingering cloudy skies will remain overnight which will
limit the amount of ridge-valley splitting and hinder fog
development. However, areas that do see precipitation would be the
better candidates to experience fog. As a result of increased cloud
cover, overnight temperatures are forecast to be on the more mild
side as overnight lows are forecast to be in the upper-60s to lower-
70s.

High pressure persists into Tuesday with very similar temperatures
and heat indices to Monday. The big difference for Tuesday is the
decreased moisture due to downsloping from easterly flow will
largely negate the chances for afternoon showers and thunderstorms.
However, can`t rule out a very very isolated chance of PoP for
Tuesday afternoon mainly for the western portions of the CWA. Cirrus
clouds are forecast to be in place Tuesday night into Wednesday
morning which may allow for a ridge-valley split to materialize and
valley fog to develop. However, this is dependent on the cloud
coverage and amount of radiational cooling that can occur.

.LONG TERM...(Wednesday through Monday)
Issued at 420 PM EDT MON JUN 17 2024

Models continue in good agreement for the pattern that will affect
our area during the long term period. Strong upper level high
pressure is expected to be centered over the Mid Atlantic states
ridging west southwest over our area through Friday. Surface high
pressure/ridging will be displaced slightly to the southeast. Our
low level flow will emanate from this high/ridge, crossing the
Appalachians and not having trajectories over the warm gulf, and
this will keep dew points from being too excessive. Meanwhile, the
upper level high will bring subsidence and warm temps aloft. This
combination should prevent deep convection, despite the early season
hot temperatures which are expected.

As we move into the weekend, the upper level ridge will break down
and an upper low/trough is forecast to move east to the upper Great
Lakes, sending the southern edge of the prevailing westerlies aloft
back south to our area. At the surface, our flow out of the high
will break down and become amorphous on Saturday. The upper level
system to our north will support a cold front which will approach
the Ohio Valley late Sunday, and our low level flow should then
become southwesterly. As the flow out of the surface high breaks
down, our air mass should begin to modify and see dew points creep
higher on Saturday, followed by advection of moisture into the area
ahead of the front late in the weekend. Along with slight cooling
aloft as the ridge breaks down, the combination may allow for a few
thunderstorms during the weekend. However, the best shot at rain is
on Monday when the cold front should arrive and provide a focus for
development.

&&

.AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon)
ISSUED AT 125 PM EDT MON JUN 17 2024

VFR conditions are prevailing across all TAF sites and will
prevail through most of the TAF period. Surface high pressure is
in place; however, showers and thunderstorms are forecast to
develop over the next few hours and increase in coverage. Opted to
add VCTS to all terminals through 01Z/Tuesday. As showers
decrease, decreasing CIGS are expected and could lead to areas of
valley fog which could impact all terminals minus KJKL.
Otherwise, light and variable winds will persist through the TAF
period.

&&

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

$$

SHORT TERM...VORST
LONG TERM...HAL
AVIATION...VORST