074
FXUS63 KJKL 291746
AFDJKL

AREA FORECAST DISCUSSION
National Weather Service Jackson KY
146 PM EDT Sun Jun 29 2025

.KEY MESSAGES...

- Hot and humid conditions will continue into early next week.
  Heat indices will peak in the 90s to around 100 degrees through
  Monday.

- Diurnal shower and thunderstorm chances continue into the first
  half of this coming week.

- A potential cold front passage toward the middle of this coming
  week could bring temporary relief from the sustained heat and
  humidity.

- Daily high temperatures might return to the 90s from next
  Saturday onward.

&&

.UPDATE...
Issued at 1230 PM EDT SUN JUN 29 2025

At just past noon, an extensive cumulus field is rapidly
developing as thermometers approach the convective temperature.
Areas most likely to experience a shower or thunderstorm this
afternoon and evening appear to be southwest of KY-15 (roughly
Whitesburg to Stanton). Convective initiation is likely to occur
first over the higher summits of Black Mountain and adjacent
ridges as well as near/west of the Pottsville Escarpment. Similar
to yesterday, cell motions will be slow, generally be under 10
mph unless a substantial cold pool develops. Given high PWATs and
and a deep warm layer, locally excessive rainfall will again be a
threat under the most intense and persistent cores.

UPDATE Issued at 753 AM EDT SUN JUN 29 2025

A fairly comprehensive update has been sent out and uploaded to
NDFD. However, there are no significant changes to the forecast or
forecast reasoning for the near-term and short-term periods.

UPDATE Issued at 1145 PM EDT SAT JUN 28 2025

No significant changes were made to the forecast with mainly just
the inclusion of the latest obs and trends for the T/Td/Sky grids.
Did also fine tune the PoPs and weather through the rest of the
night. These minor adjustments have been sent to the NDFD and web
servers along with a freshening of the zones, HWO, and SAFs.

UPDATE Issued at 855 PM EDT SAT JUN 28 2025

00Z sfc analysis shows a weak pressure pattern through eastern
Kentucky allowing the diurnal cycle to dominate. This means
convection peaking in the late afternoon and early evening each
day. Our current bout of showers and thunderstorms have worked
through much of the western portion of the CWA in association with
a large outflow boundary progressing east. Most activity in the
wake of this has had a hard time sustaining itself as instability
is waning. Currently, temperatures are running in the mid 70s
within the more rain cooled areas and in the low 80s elsewhere.
Meanwhile, amid generally light winds away from any storms,
dewpoints are mostly in the upper 60s to low 70s. Have updated the
forecast mainly to add in the latest obs and trends for the
T/Td/Sky grids but also to fine tune the PoPs per current radar
and CAMs guidance through the night. These minor adjustments have
been sent to the NDFD and web servers.

&&

.SHORT TERM...(This evening through Sunday night)
Issued at 340 PM EDT SAT JUN 28 2025

A slightly cooler and less humid air mass is noted over eastern
Kentucky late this afternoon with widespread temperatures in the 85
to 90 degree range for elevations below 1,500 feet ASL. While there
are just a few spotty radar returns showing up in our area, mainly
in the I-64 corridor at 1930z, regional radar shows multiple
clusters and loosely organized lines of showers and thunderstorms
slowly advancing eastward through Central Kentucky. This activity
has developed ahead of a slow-moving vort max disturbance
embedded in the westerly flow aloft. Sporadic convection is also
sagging into southern Indiana and Ohio with a stalling cold
frontal boundary.

As the disturbance approaches, CAM guidance has struggled to resolve
the evolution of the associated convection. Shear is minimal and
thus limiting overall storm organization, however, 2,500 to 3,500
J/kg of MUCAPE in an uncapped environment has allowed for upstream
convection to develop and establish a cold pool which is now likely
aiding in maintenance of the linear storm structure. High PWATs
in the 1.6 to 1.8 inch range, combined with relatively slow cell
movement to the east northeast at 10 to 20 mph, may pose a risk
for isolated high water/flash flooding, especially if multiple
storm cores pass over the same location, or if a heavier cell
impacts a location that received heavy rainfall yesterday. An
isolated strong to perhaps damaging wind gusts can also not be
ruled out under the most intense cores through sunset.

Expect most if not all convection to dissipate after sunset with the
loss of daytime heating. A stray shower or storm cannot be ruled out
overnight, but a vast majority of the area should be rain-free.
It will be muggy but a little cooler than recent nights with lows
in the 65 to 70F range for most places. The stalled cold frontal
boundary will pull away to the northeast as a warm front on
Sunday, but additional weak perturbations in the westerly flow
aloft are likely to aid in additional convection development,
primarily during the afternoon/early evening, coincident with
peak heating. Isolated instances of high water as well as a stray
damaging wind gust or two will once again be possible. Look for
high temperatures in the 85 to 90F range on Sunday. Sunday night
appears similar to Saturday night -- leftover convection mostly
wanes after sunset, though a stray shower or storm remains
possible overnight as temperatures settle back to between 66 and
71F.

.LONG TERM...(Monday through Saturday)
Issued at 424 PM EDT SAT JUN 28 2025

The 28/12z model suite analysis beginning Monday morning shows a
digging trough, extending from Northern Ontario to the Central
Plains, diving southeastward toward the Lower Ohio Valley. A
surface cold front initially trails from an ~1003 mb low over
James Bay southwestward across Lower Michigan and well beyond
into the eastern Kansas Plains.

This system is slated to bring temporary relief from the
heat/humidity mid-week before upper level ridging tries to re-
establish its grip on the Coalfields next weekend. The parent
trough drops into the Commonwealth by Monday and early Tuesday,
along with an associated surface cold front, and finally sweeps
away the muggy, high PWAT air mass that is currently plaguing the
region. Some modest increase in shear is likely along/ahead of
the cold front, but the overnight/morning frontal passage will
occur when instability is minimized. Similar to recent days,
disturbances aloft/ahead of the cold front are likely to bring
another round of scattered showers and thunderstorms on Monday
prior to boundary`s arrival. Rain chances are favored to linger on
Tuesday as the front makes a slow departure. As the 500H trough
slowly shifts eastward on Wednesday and Thursday, incoming
large-scale ridging will support high pressure building in at the
surface. However, a few weak disturbances riding down the eastern
side of the ridge might be able to spark a very isolated shower
or thunderstorm. A gradual warming trend is also likely as 500 mb
heights rise back to around 592 dam.

Sensibly speaking, expect more of the typical summertime showers and
thunderstorms, most numerous during the afternoon and evening, on
Monday before a period of more widespread showers and
thunderstorms move through Monday Night into Tuesday. Mostly sunny
days and mostly clear nights with just an isolated (~20% or
lower) shower or thunderstorm threat follow from Wednesday onward.
Fog can be expected in the valleys on most nights, least
extensive Monday night. Temperature-wise, daily maximum
temperatures in the 85 to 90F range on Monday cool to the 81 to
86F range on Tuesday. Nighttime lows dip solidly into the lower
and mid 60s for most as well. From then onward, look for
temperatures to gradually warm back to between 90 and 95F on
Saturday. The Independence Day holiday is shaping to be mostly
sunny and seasonably hot with just the small chance of an isolated
shower or thunderstorm.

&&

.AVIATION...(For the 18Z TAFS through 18Z Monday afternoon)
ISSUED AT 146 PM EDT SUN JUN 29 2025

The cumulus field over eastern Kentucky at TAF issuance is likely
to blossom into scattered showers and thunderstorms this
afternoon and evening. While VFR conditions should generally
prevail through sunset, briefly reduced flight categories are
likely under any passing shower or storm. Once deep convection
diminishes, fog formation is favored again tonight in the typical
valleys. However, any fog impacts at the TAF sites is uncertain,
likely dependent upon where/when rainfall occurs. Fog clears after
sunrise on Monday with renewed chances for storms by the end of
the period. Winds will be variable, generally under 5 kts, through
tonight, except potentially gusty and erratic near thunderstorms.

&&

.JKL WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

UPDATE...GEERTSON
SHORT TERM...GEERTSON
LONG TERM...GEERTSON
AVIATION...GEERTSON