813
FXUS63 KJKL 260912
AFDJKL

AREA FORECAST DISCUSSION
National Weather Service Jackson KY
512 AM EDT Sun May 26 2024

.KEY MESSAGES...

- There is a potential for severe thunderstorms today and tonight,
  with damaging winds, large hail, and isolated tornadoes
  possible.

- Showers and thunderstorms are possible through the middle of the
  week, mainly during the afternoon.

- A cold front will usher cooler air into the area from Tuesday
  through Friday.


&&

.SHORT TERM...(Today through Monday)
Issued at 4 AM EDT SUN MAY 26 2024

High resolution guidance continues to signal the potential for
several rounds of showers and storms today and tonight. For early
this afternoon, warm air advection will pick up in the low levels.
Mass convergence ahead of this will cause scattered storms to
develop. There is some uncertainty as far as coverage, so kept
PoPs in the likely category for now. Despite moderate instability,
bulk shear remains rather low, so severe potential remains modest.

There may be a weakening convective system diving southeast
through the region late this afternoon into the evening. This will
likely be accompanied by some gusty winds and will be followed by
a cooler, more stable airmass.

Finally, a third line of convection will likely impact eastern
Kentucky late tonight. Wind fields will be much stronger with this
convection, leading to the potential for strong to severe
thunderstorms. However, while bulk effective shear lifts to 40-50
knots, instability should remain somewhat modest due to the
previous convection during the day. Will need to monitor this
closely with future updates.

The cold front itself will finally make its way through the area
Monday. By then, wind fields will have decreased some... but
there remains enough instability for scattered showers and storms.
Suppose a strong gust or two cannot be ruled out with this
frontal convection, particularly in the southeast during the
afternoon.


.LONG TERM...(Monday through Saturday)
Issued at 552 PM EDT SAT MAY 25 2024

We will start off the period on Monday on the heals of an impactful
weather system Sunday and Sunday night. By Monday morning, the cold
front associated with this strong surface and upper level system
will quickly traverse KY, exiting the east side of the state by
~18Z. A line of showers and thunderstorms will likely be present
along the frontal boundary, one of several lines that will impact
the CWA through Monday morning.

Precip should taper off behind the front by Monday evening, giving
way to drier wrap around air from the surface and upper level low.
This influx of drier air will help to clear out clouds, and will
also advect in a cooler airmass from our north, despite surface
winds remaining from the W to SW. Overnight lows will settle in the
50s, around 5 to 10 degrees less than the previous night.

The strong and broad-reaching upper level trough axis will persist
across the state through midweek before finally starting to shift
eastward Thursday, where it will stall again through the remainder
of the period.

During this time, several other upper level lows will rotate through
the trough, bringing unsettled weather to the Ohio Valley and Great
Lakes at times. The first of these will be on Tuesday. All the
models have a different solution on how this will play out, with the
ECMWF and NAM keeping eastern KY mostly dry. However, the GFS brings
the shortwave farther south and precip moves across much of the
state late in the day. The NBM has trended down on pops related to
this system, only bringing in some slight chances in the far east and
northeast of the CWA Tuesday afternoon with peak heating. Didn`t see
any reason to increase it at this point, and models are still
evolving on Day 4. A similar situation arises on Wednesday afternoon
as a shortwave moves through the trough as the axis begins to shift
eastward. Models show the potential for precip to graze eastern KY
during this time, mainly during afternoon peak heating. The NBM
followed suit by another day of isolated pops for a few hours in the
afternoon in the NE CWA.

During the time that the trough is impacting the Ohio Valley, strong
N to NW flow will be in place aloft. This will keep temperatures at
or just below seasonal normals for this time of year during the day.
During the overnight, good radiational cooling with light winds will
help to quickly drop temperatures. It will also lead to some decent
ridge/valley differences in temperatures as well. Expect
temperatures to generally be in the upper 40s and low 50s, some 5 to
10 degrees below normal.

A gradual warm up will be on tap again as we close out the week and
head into the weekend. The trough will continue to shift east,
introducing a strong but short-lived ridge across the region, and
surface high pressure. Rising heights and the imposing high pressure
system should keep conditions dry both Thursday and Friday. From
this point forward there is quite a bit of disagreement. A storm
system generally over the Plains seems to stay in place through the
end of the forecast period, keeping high pressure across JKL through
the end of the period. The NBM, however, shows a quicker progression
of this system eastward, introducing pops into the CWA by Friday
night and continuing into Saturday. The fact that they are only
isolated, however, is hopefully a trend towards the drier
solutions. &&

.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
ISSUED AT 241 PM EDT SAT MAY 25 2024

Largely VFR conditions are forecast during the period, with a
couple of localized exception. A few showers/thunderstorms with
sub-VFR conditions are possible late this afternoon and evening.
Valley fog is also expected to develop late tonight and last into
Sunday morning before dissipating. MOS guidance is hitting the fog
fairly hard at TAF sites. However, if precip does not occur, it
would seem to be more questionable. A TEMPO group for IFR
conditions has been used in the TAFS for several hours around
sunrise.

&&

.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
ISSUED AT 241 PM EDT SAT MAY 25 2024

Largely VFR conditions are forecast during the period, with a
couple of localized exception. A few showers/thunderstorms with
sub-VFR conditions are possible late this afternoon and evening.
Valley fog is also expected to develop late tonight and last into
Sunday morning before dissipating. MOS guidance is hitting the fog
fairly hard at TAF sites. However, if precip does not occur, it
would seem to be more questionable. A TEMPO group for IFR
conditions has been used in the TAFS for several hours around
sunrise.

&&

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

$$

SHORT TERM...HOGUE
LONG TERM...JMW
AVIATION...HOGUE