035
FXUS63 KJKL 270625 AAC
AFDJKL

AREA FORECAST DISCUSSION...UPDATED
National Weather Service Jackson KY
225 AM EDT Thu Jun 27 2024

.KEY MESSAGES...

- Hotter weather is expected to make a comeback by Friday and
  especially Saturday, with afternoon highs in the low to mid 90s
  and heat index values peaking around or in excess of 100F.

- A passing cold front will bring likely rainfall to the area
  Saturday night into Sunday, followed by another shorter-lived
  cooldown for early next week.

&&

.UPDATE...
Issued at 225 AM EDT THU JUN 27 2024

Grids were updated based on recent radar and observation trends.
Lightning has not been detected over eastern KY during the past
couple of hours and is not expected during the overnight hours and
thus thunder was removed to the forecast for the overnight.

UPDATE Issued at 1040 PM EDT WED JUN 26 2024

The stronger storms have mostly died out with only one last
cluster rolling east through the southern Cumberland Valley.
Otherwise, showers (with an occasional lighting flash) will
gradually diminish into the early overnight hours followed by some
clearing. This will likely result in areas of low clouds and fog -
locally dense - to develop. Have updated the forecast to fine tune
the convection`s departure to the southeast through the night.
Did also add in the latest obs and trends for the T/Td grids.
These adjustments, and the dropping of the severe watch, have
been sent to the NDFD and web servers along with a freshening of
the zones, HWO, and SAFs.

UPDATE Issued at 755 PM EDT WED JUN 26 2024

23Z sfc analysis shows eastern Kentucky in the warm sector of a
larger system just to the west of the state. This allowed the
area to heat up with ample instability triggering several
thunderstorm clusters - a few of which became severe. Much of the
area is now worked over by the earlier, and current, convection
as the next round approaches from the northwest. The latest CAMs
guidance and radar extrapolation indicate that the Cumberland
Valley will be most under the threat of severe weather - mainly
in the form of damaging wind gusts. Have updated the PoPs and
thunder chances through the night per this scenario along with
beefing up the fog due to the added rains of this evening.
Otherwise, temperatures are running in the low 80s in places
spared the convection but in the low to mid 70s where the rain
occurred. Meanwhile, amid generally light and variable winds
(outside of any storms), dewpoints remain elevated in the upper
60s to lower 70s for most. With this update, in addition to the
PoP and Wx adjustments have also included the latest obs and
trends for the T/Td/Sky grids. These changes have been sent to
the NDFD and web servers along with the earlier updates to the
zones, HWO, and SAFs to account for the severe watch that remains
in effect until 10 PM EDT.

&&

.SHORT TERM...(This evening through Thursday night)
Issued at 256 PM EDT WED JUN 26 2024

Current surface analysis is pretty busy as there`s multiple
disturbances moving across the eastern CONUS. The most significant
of them is a surface low moving across the Upper Great Lakes.
Extending southwest from the occluding low is a stationary front.
Also, riding along the boundary is another surface low moving out of
the Ozarks. All of this is forecast to move toward the Commonwealth.
Locally, a weak line of showers is moving across the northern tier
of counties with a couple weak echos showing up along the Mountain
Parkway. Also, temperatures across the area are already climbing
into the upper-80s to low-90s which will maximize ahead of the cold
front.

This afternoon brings an upper-level trough that`ll pivot southeast
toward the CWA this afternoon. That pivoting will push that
aforementioned surface low and cold front toward the Commonwealth.
The SPC has increased our severe weather risk to include much of the
entire CWA minus a few cities along the KY/TN border. Forecast
soundings from across the area continue to show somewhat favorable
severe weather indices. Both MUCAPE, SBCAPE and DCAPE are all
favorable for severe storms, steep low-level lapse rates are in
place as well. Significant shear is slightly lacking but there`s
enough out there to favor a few longer lasting storms. Lastly, PWs
continue to run about 2" which if a storm is efficient enough will
allow for some heavy rainfalls. The front will slowly track through
the area this afternoon and overnight hours before exiting early
early tomorrow morning. Widespread fog is possible tomorrow morning
but will burn off with increasing daytime heating.

Height rises ahead of surface high pressure is expected to build
into the region for Thursday morning and persist through the
remainder of the forecast period. Temperatures for Thursday will be
slightly cooler with highs climbing into the mid-80s and overnight
lows dropping into the upper-50s to low-60s which will bring an end
to an active period.

.LONG TERM...(Friday through Wednesday)
Issued at 553 PM EDT WED JUN 26 2024

The models remain in generally good agreement through the middle
of next week. Ridging will dominate across the southern third of
the CONUS, with the center of this ridge establishing itself over
the southern Plains through this weekend, before elongating and
shifting east with time through next week, mostly maintaining the
ongoing heat across the region. Meanwhile, bouts of passing short
wave energy will skirt east, with the core of this energy
affecting the northern tier of states across the CONUS. Still,
residual short wave troughing will pass through the Ohio Valley at
times, yielding intermittent threats of convection across our
area, and at least some temporary relief from the hotter weather.

The heat will be in full swing Friday and Saturday, with highs in
the lower 90s, yielding peak heat indices of around 100 degrees
for some locations on Friday, and between 100 and 105 degrees on
Saturday. Lower PoP chances (20-30%) will be possible across the
southeastern half of our area Friday afternoon. Better moisture
return then ensues for Saturday, with most places seeing a good
chance (50%) of afternoon showers and thunderstorms. Overall, the
best forcing and instability will be coincident Saturday night
into Sunday, with PoPs peaking in the 70-80% range across our area
during that time. Drier and temporarily cooler weather will return
for the new work week behind the associated departing cold front.
Highs will retreat to the 80s, while temperatures dip into the
upper 50s and lower 60s at night. The heat will then make a
comeback by Tuesday and Wednesday, with lower 90s returning. While
a stray storm or two can not be ruled out Tuesday afternoon, the
areal coverage looks to be pretty limited, due likely to capping
associated with higher 500 mb heights over the region. As such,
kept PoPs below 15% this go around. Chance PoPs (40%) will occur
by Wednesday, with an increase in moisture ahead of another
approaching cold front from the northwest.

&&

.AVIATION...(For the 06Z TAFS through 06Z Thursday night)
ISSUED AT 210 AM EDT THU JUN 27 2024

Showers or light rain remained across the south at issuance time
as a cold front sags south. A wide range of conditions were
reported with VFR in some areas, with some MVFR or IFR reductions
where the rain was falling and also further north behind the
boundary. A few locations were reporting conditions at or below
airport minimums. An overall trend toward more widespread low
CIGS or visibilities to MVFR and IFR if not LIFR or VLIFR is
expected during the first 6 hours of the period. The reductions
should begin to improve around 13Z. The reductions should persist
longest in portions of the south, but VFR should prevail in all
areas by 18Z as high pressure builds into the area. Winds are
expected to be light and variable through the period.

&&

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

$$

UPDATE...JP
SHORT TERM...VORST
LONG TERM...GEOGERIAN
AVIATION...JP