430
FXUS63 KJKL 301928
AFDJKL

AREA FORECAST DISCUSSION
National Weather Service Jackson KY
328 PM EDT Tue Apr 30 2024

.KEY MESSAGES...

- Isolated to scattered showers this afternoon, with perhaps a
  rumble of thunder. Not as warm.

- Dry and trending warmer midweek, with near record highs on
  Thursday.

- Unsettled weather returns for Friday and lingers through early
  next week.

&&

.UPDATE...
Issued at 1232 PM EDT TUE APR 30 2024

Steadier showers have moved east and southeast of eastern KY this
morning with isolated to scattered showers lingering behind it.
Hourly grids have been updated for recent radar and observation
trends.

&&

.SHORT TERM...(Today through Wednesday)
Issued at 335 AM EDT TUE APR 30 2024

Rain showers have arrived to the far southwest counties of the
forecast area as of this early-morning writing. Rain will continue
to progress slowly NNE through the day. I`ve removed the thunder
chance early this morning as instability is best over northern
Alabama, where thunder prevails at this time. There is a subtle
resurgence in instability by midday, but this varies greatly from
model to model. I say subtle because there will be plenty of
clouds to overcome. Lapse rates are generally be poor as well.
Additionally, in the wake of this cold front, a forcing mechanism
for any late-afternoon redevelopment is absent. Therefore, have
generally capped the thunder at "chance" today with dry weather
prevailing from west to east as this line of rain exits. Rainfall
today will generally total around 0.25" to as much as 0.50".

Clearing skies tonight with light wind. Add to the mix the fresh
rainfall and fog is likely overnight in the valleys.

500-mb heights will be on the rise Wednesday due in part to some
deepening of a trough over the Northern Rockies. This will propel
our highs back into the 80s following the  seasonably cool
temperatures of Tuesday.

.LONG TERM...(Thursday through Tuesday)
Issued at 327 PM EDT TUE APR 30 2024

The period begins with good agreement in the deterministic and
ensembles on the mid-level ridging the Southeast US and high
pressure off toward the Atlantic Coast line. This will keep the
weather quiet, with very dry low levels and capping inversion
aloft. This could lead to some flat cumulus in the afternoon, but
very warm afternoon high temperatures in the mid-80s to near 90
degrees. This could eclipse record high temperatures, with JKL 87
degrees set in 2012 and LOZ 88 degrees set in 1959. The ridging
does push east as a mid-level wave rides toward the Ohio Valley
Thursday night into Friday. This will aid in giving way to showers
and thunderstorms Friday afternoon, as moisture surges northward
and small amount of instability comes with it. This as multi-model
ensembles show 40-50 percent chance of greater than 250 J/kg of
CAPE.

Overall guidance, including ensembles are in good agreement with
best chance of rain (around 60-70 percent) Friday night into
early Saturday. There seems to be a little uncertainty on Saturday
in terms of timing, with first wave and next shortwave pushing
into the Midwest, Saturday night into Sunday. The deterministic
and ensemble data are disagreeing on the amplitude of this wave
too and leads more uncertainty by late weekend into early next
week. Particularly as there could be some shortwave ridging in
between these features. Therefore, the PoPs drop back into the
40-50 percent range mainly in the afternoon hours Sunday into
Tuesday. It will remain 10 to 15 degrees above normal through this
time range.

&&

.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)
ISSUED AT 215 PM EDT TUE APR 30 2024

Some isolated to scattered showers were moving across the region
as of issuance time with some IFR ceilings in the far southeast
and MVFR or VFR elsewhere. For all sites during the first 3 to 5
hours of the period, there continues to be a non-zero chance of
thunder, but the risk overall remains too low to mention.

Ceilings should trend to MVFR and VFR and then VFR areawide during
the first 3 hours of the period, though some MVFR ceilings and/or
vis are anticipated within showers. Clearing is anticipated
tonight with winds becoming calm as high pressure builds in,
setting the stage for fog development. This should particularly
affect the valleys, though it appears likely that it will affect
most areas including all of the TAF sites for at least a few hours
between 03Z and 14Z. Visibilities as low as IFR to LIFR if not
below airport minimums will be possible.

&&

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

$$

UPDATE...JP
SHORT TERM...BROWN
LONG TERM...DJ
AVIATION...JP