883
FXUS63 KJKL 031141
AFDJKL

AREA FORECAST DISCUSSION
National Weather Service Jackson KY
741 AM EDT Mon Jun 3 2024

.KEY MESSAGES...

- After a relative lull in precipitation lasting into Tuesday
  morning, the potential of showers and thunderstorms will
  increase at mid week.

- Somewhat cooler and drier weather will arrive behind a cold
  front which will pass on Thursday.


&&

.UPDATE...
Issued at 740 AM EDT MON JUN 3 2024

Have blended morning obs (temps, dew points, and sky cover from
satellite) into the forecast, without substantive changes.

&&

.SHORT TERM...(Today through Tuesday)
Issued at 533 AM EDT MON JUN 3 2024

Clouds in the 2-10K ft range have been problematic to forecast
the coverage of during the night. Where they have been most
prevalent they have inhibited fog development which was
anticipated. Areas southwest of a line from around Mt. Vernon to
Middlesboro and near/north of I64 saw the most breaks in the
clouds and have had the most fog. Even so, it does not appear more
widespread than most summer nights, and the forecast has been
allowed to handle it without special products. By first light of
dawn the clouds were trending north and east, generally northeast
of a line from Irvine to Harlan, alleviating the fog that had
developed over the northern part of the area. What fog there is
will dissipate after sunrise.

Weak ridging aloft will be passing over from west to east today
with relatively dry air aloft. Surface flow will be weak, but a
somewhat moist air mass will remain in place, with dew points in
the lower to mid 60s. The deepest low level moisture is expected
to be over the northern portion of the forecast area, and both the
NAM and GFS have light precip there as convection bubbles up
during the day, and a 20% POP has been used. The HRRR also shows a
bit of convective precip over the more rugged terrain of
southeast KY this afternoon, and that can`t be completely ruled
out either. Any precip will eventually die out this evening as
stabilization occurs.

By Tuesday the aforementioned ridge will be to our east, and a
weak shortwave embedded in a larger area of troughiness will be
approaching from the west. This may bring more
showers/thunderstorms, especially with diurnal heating. The GFS is
the most aggressive with the precip making across the forecast
area on Tuesday, but even the NAM has some in our southwest
counties in the afternoon, while the HRRR has a spattering area
wide. A blended solution suggests a slight chance (20%) in our
eastern counties and a chance (30-40%) elsewhere.

.LONG TERM...(Tuesday night through Sunday)
Issued at 353 AM EDT MON JUN 3 2024

An amplified and blocky long wave pattern will be in place through
the period. Model agreement has improved somewhat late in the
week compared to yesterday. Deeper short wave energy will take on
a negative tilt as it moves from the central/northern Plains to
the Upper Midwest and Great Lakes/lower Ohio Valley region by
early Wednesday morning. A surface cold front will progress
southeast, aligning from portions of the Great Lakes and Ohio
Valley back through the Midwest and into the southern Plains by
early Wednesday morning. Deeper moisture and lift will move
through the Ohio and Tennessee valleys later Wednesday
afternoon/evening, associated with a passing short wave trough, as
well as the nearing surface cold front. Consequently, widespread
convection will break out across eastern Kentucky, with good model
agreement maintaining that this will likely be our most active
period.

As the parent upper level low gradually spreads southeast from
south central Canada into the Great Lakes and portions of the Ohio
Valley through the end of the work week, cooler and drier air
will eventually overspread our region. While PoPs will not be
eliminated from the forecast, given the cyclonic flow in place,
they will lessen through Friday, with only a 20% chance forecast
by that time. PoPs will then increase to the chance range (20-40%)
through the end of the week, as the upper level low continues to
gyre around the eastern Great Lakes and portions of New England.
This will allow for another progressive surface cold front to move
through the Ohio Valley. Details on the timing are low confidence
at this time, so have continued to keep PoPs aligned more with the
diurnal cycle.

Temperatures will average several degrees above normal through
mid-week, with highs in the low to mid 80s and lows in the low to
mid 60s. Highs will then retreat to the mid to upper 70s on
Friday, before modifying back closer to normal by Sunday, with
temperatures peaking near the 80 degree mark. Lows will generally
range from 55 to 60 degrees.

&&

.AVIATION...(For the 12Z TAFS through 12Z Tuesday morning)
ISSUED AT 740 AM EDT MON JUN 3 2024

Fog is affecting some places early this morning, especially
valleys, resulting in localized IFR or worse conditions. The fog
will dissipate shortly, perhaps lifting into a MVFR ceiling for a
time before clouds further lift and scatter out during the day.
Mainly VFR conditions are forecast from early afternoon on. There
is a slight chance of showers and thunderstorms from mid day
through the afternoon in northeast KY and near the VA border,
which could bring very localized sub-VFR conditions. Valley fog
is also forecast late tonight, but is not expected to affect TAF
sites.

&&

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

$$

UPDATE...HAL
SHORT TERM...HAL
LONG TERM...GEOGERIAN
AVIATION...HAL