667
FXUS63 KJKL 020015 AAA
AFDJKL

AREA FORECAST DISCUSSION...UPDATED
National Weather Service Jackson KY
815 PM EDT Tue Jul 1 2025

.KEY MESSAGES...

- Showers and thunderstorms will pass across eastern Kentucky
  this evening

- Enjoy drier and more comfortable conditions for Wednesday and
  Thursday.

- Independence Day looks beautiful and very warm, with mostly
  sunny skies and highs in the upper 80s to lower 90s, perfect for
  outdoor celebrations!

- Starting this weekend and into early next week, prepare for
  increasing heat and humidity, which will make it feel like the
  90s, along with daily chances for pop-up showers and
  thunderstorms.

&&

.UPDATE...
Issued at 800 PM EDT TUE JUL 1 2025

23Z sfc analysis shows weak low pressure slipping off to the east
while some high pressure is poised to enter from the west. This
transition is clearing the threat of showers and thunderstorms off
to the east while drier and quieter weather is inbound from the
northwest. Currently temperatures are running in the mid to upper
70s away from any showers or thunderstorms to the low 70s amid the
convection. Meanwhile, amid light and variable winds, dewpoints
are generally in the upper 60s northwest to the low and mid 70s in
the southeast. 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 and Wx per the current radar and CAMs guidance through
the night. These adjustments have been sent to the NDFD and web
servers along with a freshening of the zones, HWO, and SAFs.

&&

.SHORT TERM...(This evening through Wednesday night)
Issued at 254 PM EDT TUE JUL 1 2025

Current surface analysis has the forecast area under the warm sector
regime ahead of an approaching cold front. The parent surface low,
responsible for the front, is located over southern Canada but the
front itself is extended southwestward from the surface low through
the Commonwealth and down to the High Plains of Texas. As the front
approaches, increasing showers and thunderstorms are expected with
storms chances maximizing ahead of FROPA. Locally, showers and
thunderstorms are developing with the backside of the front in
western Kentucky.

Through the remainder of the day, the front will approach the area
bringing increased chances of showers and storms. Widespread severe
weather isn`t expected due to a lack in deep instability and
mediocre shear values. However, can`t rule out a stronger
thunderstorm this afternoon. Also, a long, skinny CAPE profile
exists meaning that efficient storms are expected and with PWATs
upwards and over 2.00"; heavy rainfall can be expected with any of
these showers. Fortunately, the activity appears to progressive and
that should mitigate the flash flooding/hydrology threat. Once the
front passes late tonight, surface high pressure will build into the
area ushering in cooler and drier air.

Surface high pressure lingers through Wednesday into Thursday
leading to drier weather through the rest of the period. Temperatures
will rebound back into the mid-80s for Wednesday but dry
northwesterly flow will bring dewpoints down into the mid to upper-
60s leading to a dry-heat compared to the oppressive heat we saw the
last few days.

In summary, a cold front will cross through the CWA today bringing
showers and storms. Highs will climb into the low to mid-80s pre-
frontal. Once FROPA occurs, surface high pressure will build into
the region with high temperatures climbing into the mid-80s.
Overnight lows will still remain in the low to mid-60s.

.LONG TERM...(Thursday through Tuesday)
Issued at 350 PM EDT TUE JUL 1 2025

The long-term period analysis opens on Thursday morning with a
500H trough extending southward from Quebec into the Northeast and
Mid-Atlantic. At the same time, a 500H ridge extends from the
Gulf of America northward through the Central Plains and into
Manitoba/Saskatchewan. Translating down to the surface, an ~1018
mb high is centered over the Mid-Mississippi Valley but is
expansive and already very much in control of the weather over
eastern Kentucky. Deep layer northwesterly flow to the east of the
surface high and upper-level ridge is feeding a warm but dry
continental air mass into the Eastern Kentucky Coalfields.

As the aforementioned trough departs into the Canadian Maritimes
and West Atlantic, the upper-level ridge axis will translate
eastward to a position over the Commonwealth Saturday morning. The
associated surface reflection strengthens as it lifts northeast
and becomes an ~1022 mb high centered near/over Eastern
Pennsylvania. Moisture levels, remaining relatively low under a
continental air mass, will begin to inch higher beginning Saturday
as a southerly flow from the subtropics develops on the backside
of the surface high. PWATs will rise back into the 1.5 to 1.8 inch
range by Monday and Tuesday (or to between the 75th and 90th
percentile relative to climatology). At the same time, the upper-
level ridge flattens with a notable weakness developing over the
Ohio Valley between a Pacific shortwave trough passing through the
northern CONUS and a potential upper low of tropical origin
trying to press northward. Specific details become more obscure
due to increased model spread during the last couple days of the
forecast period, but the return of diurnally modulated deep
convection is probable from Sunday onward.

In sensible terms, a dry warming trend will be underway on
Thursday and continue right into the upcoming weekend with mostly
sunny days and mostly clear nights. High temperatures on Thursday
reach the mid to upper 80s, upper 80s to lower 90s on Friday, and
lower to mid 90s on Saturday. Moderate dew points will allow for
good cooling at night though with low temperatures forecast in the
lower to middle 60s on Thursday night and mainly middle 60s on
Friday night. Heading into early next week, the increasing
humidity levels will help limit the diurnal temperature range a
few degrees with highs slipping to near 90 degrees for Monday and
Tuesday while nighttime minimums moderate to near 70 degrees. In
spite of the cooling daytime highs, the higher humidity levels
will still result in heat indices rising well into the 90s on both
afternoons. Also, with that rise in moisture, we will see the
return of daily pop-up shower and thunderstorm chances from Sunday
onward.

&&

.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
ISSUED AT 815 PM EDT TUE JUL 1 2025

Showers and storms are working across the eastern portion of the
aviation forecast area with this TAF issuance having already
passed most of the TAF terminals. The activity will still cause
short-lived reductions in category when there`s activity at a
terminal but recovery back to VFR is rather quick. SJS looks to
have the best chance of seeing a storm during the next couple of
hours. Once a cold front crosses through later this evening,
surface high pressure will build into the region drying us out
for the remainder of the TAF period. Guidance still suggests that
widespread fog will develop but that will be largely dependent on
how much clearing can be achieved overnight. If fog does develop,
expect categorical reduction at TAF sites to IFR or lower. Fog
will then clear out by 14Z allowing all sites will return to VFR.
Winds will be light and variable, for the most part, through the
period.

&&

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

&&

$$

UPDATE...GREIF
SHORT TERM...VORST
LONG TERM...GEERTSON
AVIATION...VORST/GREIF