132
FXUS63 KJKL 031222
AFDJKL

AREA FORECAST DISCUSSION
National Weather Service Jackson KY
822 AM EDT Fri May 3 2024

.KEY MESSAGES...

- Shower and thunderstorm potential returns to the forecast
  through the next 7 days.

- Cooler than in recent days, but temperatures are forecast to be
  above normal through the next 7 days.

&&

.UPDATE...
Issued at 822 AM EDT FRI MAY 3 2024

Expanded low-end PoPs slightly eastward this morning to account
for isolated shower activity developing where PoPs < 15. Also
raised QPF slightly especially this afternoon and mainly along the
westernmost tier or two of counties. Otherwise, blended in hourly
temperatures to the forecast.

UPDATE Issued at 700 AM EDT FRI MAY 3 2024

Made a quick early update to the forecast grids. Based on obs
from the past few hours, temperatures have simply not fallen off
as far as originally forecast, especially in our normally cooler
eastern valleys. Therefore, modified this mornings lows to reflect
the latest obs trends. Will leave the zone forecast text product
as is to continue covering early morning shower activity. Another
update will be needed in the next hour or two to remove the pre-
first period and make any further necessary updates.

&&

.SHORT TERM...(Today through Saturday)
Issued at 500 AM EDT FRI MAY 3 2024

The 6Z surface chart out of the WPC showed a large occluded low in
place over northwestern Minnesota, with an occluded front  extending
southeast from it. A cold front and semi-stationary boundaries were
snaking their way southwest and east from the triple point with the
occluded boundary, with each boundary extending out to the east
coast and beyond and out to western Nevada. Waves of low pressure
were also seen at various locations from Utah to southwest Texas, to
Indiana, and just off the Mid-Atlantic coast. High pressure was in
place over portions of the central Plains and upper Mississippi
Valley, with  large subtropical low in place off the southeastern
CONUS.

A complex pattern in place across the country to be sure to start
off this Friday. We will see showers and thunderstorms moving
through our area from time to time today through Saturday, as the
occluded low moves eastward into the Great Lakes and eventually into
central New England. As the low moves off to the east or northeast,
the surface boundaries extending south from it will move through the
region, and will spark showers and storms across area. Based on
current model data, it is clear that there will be instability and
moisture in place to fuel showers and thunderstorms across eastern
Kentucky, but uncertainty exists as to exactly where storms will
fire and how extensive the rain will be. Some models have been
showing few if any showers and storms across eastern Kentucky over
the next couple of days, while others have fairly extensive coverage
of precipitation. There is also some doubt revolving around how well
defined any boundaries will be as they move through our area. That
all being said, with a good influx of moisture and instability into
the region, we expect scattered to numerous showers and scattered
storms to fire and move through the area from time to time today
through Saturday, with the afternoon and early evening hours being
most active due to peak heating and maximized instability. It does
appear that Saturday will be a bit more active than today, as the
model data is showing quite a bit more instability present than
today, especially late Saturday afternoon.

Temperatures will continue to run well above normal, with highs in
the upper 70s to lower 80s on tap today and Saturday. Enough
decoupling may occur late Friday night to allow for a small ridge
valley split, especially in the northeast where our normally cooler
valleys may fall off into the mid 50s. As far as weather hazards go,
we are not expecting anything of major concern at this time. As
always, any thunderstorms we see the next couple of days will be
capable of producing dangerous cloud to ground lightning, gusty
winds, and locally heavy downpours that could lead to ponding of
water on roadways or short lived minor nuisance flooding.
Confidences is high that most locations will see rain today through
Saturday, its a matter of how widespread will thunderstorms be,
especially today with less instability expected.

.LONG TERM...(Saturday night through Thursday)
Issued at 500 AM EDT FRI MAY 3 2024

A rather wet long term period should be in store. However, it
looks overall rather short on details/specifics. Prevailing large
scale flow aloft will be persistent from the west southwest, while
low level flow will be from the south southwest off the gulf.
This pattern of warm/moist advection will favor precip. A wavering
frontal boundary will approach from the northwest at times, but
being largely parallel to the upper level flow, it will not have
much momentum and is not likely to make a clean passage during the
period (possibly just beyond the current long term period). This
will leave us in a modestly humid air mass with surface dew points
in the upper 50s and lower 60s most of the time. The main drivers
for precip will be convection associated with diurnal heating
cycles and mid/upper level waves. While the diurnal cycle is
simple, weak upper level features are much more problematic. The
most obvious and predictable feature at this point is a shortwave
trough which all models have approaching on Monday. The highest
POP (70% area wide) of the long term period coincides with this.
The remainder of the 12 hour periods have POPs mainly in the
40-60% range.

&&

.AVIATION...(For the 12Z TAFS through 12Z Saturday morning)
ISSUED AT 700 AM EDT FRI MAY 3 2024

Scattered rain showers have begun moving into our southwestern
counties early this morning, with SME and LOZ seeing the first
rain. VCSH is being used to handle the early morning activity, but
it appears that enough thunderstorms will fire by early this
afternoon to warrant inserting VCTS into each TAF, beginning at
18Z for SME and starting at 23Z or so at JKL and SJS. The best
time for any storms will be this afternoon into early this evening
during peak heating. Once the sun goes down, the storms should
become more isolated with time with rain showers being the
dominant precipitation mode. Rain will become more widespread as
the day wears on, with numerous light to moderate rain showers
expected this afternoon through late this evening. Any storm
could produce locally heavy rainfall and gusty winds, along with
brief periods of MVFR VSBYs. MVFR CIGs will also be possible at
times today into this evening during peak thunderstorm activity.

&&

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

$$

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