154
FXUS63 KJKL 182300 AAA
AFDJKL

AREA FORECAST DISCUSSION...UPDATED
National Weather Service Jackson KY
700 PM EDT Fri Jul 18 2025

.KEY MESSAGES...

- Thunderstorms could produce locally heavy rainfall through this
  evening, with a potential for flash flooding.

- The current regime will persist through early in the new week,
  with shower/thunderstorms expected at times, with isolated to
  scattered instances of additional flooding being a concern.

- The potential for rain will wane at mid week and heat is
  forecast to build. Heat indices are forecast to top 100 in most
  places by late week.

&&

.UPDATE...
Issued at 700 PM EDT FRI JUL 18 2025

With high PW persisting, and ongoing convection upstream as well
as signals for heavy rain this evening in some CAMS and the 12Z
HREF, opted to extend the Flood Watch for a few more hours
through the evening into 1 AM EDT on Saturday.

The pattern over the weekend with high PW and a front stalled or
nearly stalled over the OH Valley vicinity will be conducive for
additional isolated to scattered flash flooding concerns and an
extension into the weekend or a future flood watch for the weekend
is likely to be needed.

&&

.SHORT TERM...(This evening through Saturday night)
Issued at 313 PM EDT FRI JUL 18 2025

Slow moving showers/thunderstorms are ongoing over the southern
portion of the area at mid afternoon, with repeated occurrences
bringing heavy rainfall to some locations. Cape profiles are
generally tall and thin with precipitable water in the column near
or above 2". Flow aloft continues rather weak and unidirectional.
This is promoting localized training and backbuilding of cells,
but is limiting strong storms to pulse variety. The southern part
of the area will probably be largely worked over by this evening,
but there is some potential for activity still to increase in our
northern counties where it is so far remaining more sparse.

A similar scenario will be in places again on Saturday, except
there should be a weak mid/upper level wave (currently associated
with convection over MO) moving in around peak heating. This will
result in a high POP and another heavy rainfall threat.

Activity should decrease again Saturday evening. However, some
model runs suggest an MCS could make it into our northeast
counties overnight in west northwest flow aloft along the southern
edge of the prevailing westerlies, aided by decent low level west
southwesterly inflow south of an advancing cold front.

With the ongoing localized heavy rainfall, the Flood Watch
continues into the evening. If activity wanes, it may be able to
be allowed to expire. Even so, after a break, another issuance
could be needed for the increase in convection during the day
Saturday.

.LONG TERM...(Sunday through Friday)
Issued at 253 PM EDT FRI JUL 18 2025

The mean upper-level synoptic pattern indicates upper-level
troughing to the northeast of the region, with a 590 dam ridge
positioned over the Gulf Coast. The forecast area is situated
between these two features for much of the forecast period. A
stationary boundary, a remnant of a stalled cold front from the
weekend, is forecast to be oriented west to east across the
Commonwealth, which will contribute to increased shower and
thunderstorm activity through the day Sunday. Widespread severe
weather is not anticipated due to a lack of significant deep-layer
shear necessary for sustaining organized thunderstorms. However,
forecast precipitable water amounts continue to run above
climatological norms, and tall, skinny CAPE soundings indicate that
precipitation on Sunday could be efficient, leading to continued
hydrological concerns. Showers and storms are forecast to dissipate
toward sunset, leading to a quiet night with river valley fog
development.

Monday will feature conditions similar to Sunday; however, forecast
soundings indicate a trend toward a drier atmospheric column, with
PW values decreasing to approximately 1.40 to 1.60. While this
suggests a drier airmass aloft, the potential for heavy rainfall
continues to exist. As with Sunday, showers and storms will
dissipate in the late evening, giving way to overnight areas of
valley fog.

Upper-level height rises begin to propagate into the area for
Tuesday, leading to warmer temperatures. However, dew points are
forecast to decrease as streamlines indicate overland flow,
resulting in a drier airmass. This will work to limit the overall
convective potential; nonetheless, the potential for showers and
storms will be none-zero and will persist through the afternoon into
the early evening before dissipating overnight.

Height rises are forecast to increase for Wednesday and will remain
prominent through the rest of the period, leading to the warmest
temperatures of the forecast period. Rain chances will become
isolated after Wednesday, but there are still slight chances of
precipitation each afternoon through the remainder of the period.

Overall, the forecast period will be highlighted by periods of heavy
rainfall beginning Sunday and continuing through Monday. PoP chances
will begin to slowly decrease from Tuesday onward, but the threat of
rain never entirely diminishes. High temperatures will start in the
upper 80s but by Wednesday, these highs will climb into the mid to
upper 90s. Overnight lows will follow a similar warming trend.

&&

.AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon)
ISSUED AT 134 PM EDT FRI JUL 18 2025

Showers/thunderstorms are again on the increase as heating builds
instability. Will expect a mid-late afternoon peak, but some
convection may last through the night and into Saturday before
another uptick begins toward the end of the forecast period. IFR
or worse conditions may occur in showers/thunderstorms. Otherwise,
VFR conditions are forecast until tonight, when fog will begin to
affect some locations (particularly valleys which received
rainfall). Fog will again dry up on Saturday morning.

&&

.JKL WATCHES/WARNINGS/ADVISORIES...
Flood Watch until 1 AM EDT Saturday for KYZ044-050>052-058>060-
068-069-079-080-084>088-104-106>120.


&&

$$

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