970
FXUS63 KJKL 171953
AFDJKL

AREA FORECAST DISCUSSION
National Weather Service Jackson KY
353 PM EDT Thu Jul 17 2025

.KEY MESSAGES...

- Thunderstorms over the next several days could produce locally
  heavy rainfall at times, potentially leading isolated to
  scattered instances of flash flooding.

- Warm/hot temperatures and high dew points will persist,
  resulting in sultry conditions.

- There will be a daily potential for showers/thunderstorms,
  especially in the afternoon/evening hours.

&&

.SHORT TERM...(This evening through Friday night)
Issued at 323 PM EDT THU JUL 17 2025

Isolated to scattered showers and thunderstorms continue to move
across eastern Kentucky this afternoon and evening. Some of these
thunderstorms have the potential to produce strong to damaging wind
gusts, as well as heavy rainfall, and high precip rates. Rain
falling repeatedly over the same locations could lead to flash
flooding. As such the SPC has the area under a Marginal Risk for
severe weather, and the WPC has the area  under a Slight Risk for
excessive rainfall through 8 AM Friday. A Flood Watch also remains
in effect for the entire area, minus Wayne county.

Instability has been slowly "loading" across the area this
afternoon, with a widespread Surface CAPE of 3000-4500 J/kg, with
the highest values across the Bluegrass. A somewhat strong vort-
maxima precedes a surface cold front that will be slowly working
its way across the Ohio Valley this afternoon and evening. CAMS
have somewhat struggled with this pattern the last few days, with
several members across multiple runs under doing model precip
output. This is likely partly attributed to models under doing
dewpoints (or available moisture) across the area. Surface
dewpoints have been observed in the mid to upper 70s, with the
highest dewpoint of 80 being observed in Bath, Morgan, and
Breathitt so far. The NAMNEST seems to have the highest modeled
dewpoints as it relates to observations, however they still only
touch 74-75F in runs, and the model itself has struggled to handle
current radar trends.

The 09Z RAP shows a strong 500-mb Vorticity maxima along the cold
frontal passage this evening. The lift available suggests that
storms could linger through the overnight hours, and into tomorrow
morning. The potential remains that somewhere, training storms
could lead to rain totals over 2 inches, most favored along and
north of I-64.

A later run of the RAP, the 15Z is slower with the frontal passage
and has a more persistent rain Friday afternoon. Regardless, Showers
and thunderstorms are expected Friday, as quasi-zonal flow remains
off to the west, with another vort-maxima set to move into eastern
Kentucky. This vort-maxima is stronger than the last few days, and
will aid in lift and storm growth. A strong Bermuda high off the SE
Atlantic coast will continue to transport warm, moist air into the
area out of the southwest. SCAPE is elevated again tomorrow with
4000 J/kg, more than enough to support convection. PWATs will
remain near 2 inches for tomorrow, with the area in a Marginal
Risk for excessive rainfall. Rain falling repeatedly over the same
locations could lead to instances of flash flooding.

.LONG TERM...(Saturday through Thursday)
Issued at 353 PM EDT THU JUL 17 2025

The 17/12z model suite remains in good agreement on the large-
scale pattern -- a stagnant, humid, and muggy pattern will linger
through at least next Thursday. The long-term analysis beginning
Saturday morning shows an ~596 dam high over the Florida Peninsula
with a ridge axis extending west northwest to over the Texas
Panhandle. A quasi-zonal 500 hPa flow lingers atop the ridging
over the northern CONUS from the Plains eastward through New
England. A temporarily retreating boundary extends from the
Delmarva Peninsula to a weak wave of low pressure over the Upper
Midwest and then southwest into the prairies of Kansas and
Nebraska. Multiple 500 hPa disturbances (vorticity maxima) are
riding the baroclinic zone. One of those more prominent
disturbances will be riding across the Lower Ohio Valley while
additional disturbances are noted upstream over the Central Plains
and Central Rockies. PWATs remain near 150 percent of normal in
the 1.9 to 2.1 inch range.

For Saturday and Sunday, the upper level high will continue
retrograding to near the Mississippi Delta while the wavering
frontal boundary sags back toward the Ohio River. PWATs remain
high in the 1.8 to 2.1 inch range (or ~90th percentile relative to
climatology). Instability values climb to between 2,000 to 3,000+
J/kg of MUCAPE each afternoon. For the time being, not seeing a
particularly strong signal in moisture transport or convergence to
signal a potential widespread flooding event. However, the
ongoing daily rounds of showers and storms will continue to prime
our area for flash flooding for when showers and storms are most
widespread on Saturday and Sunday. The parameter space will remain
quite favorable at times for persistent training and/or repeated
rounds of convection. While it is too far out to pinpoint specific
locations where the heaviest activity might occur, the
environment appears supportive of flash flooding, perhaps locally
high impact. The ECMWF EFI does show a weak signal for an unusual
QPF event north of the Mountain Parkway from Friday night through
Saturday--however, mesoscale and topographic effects are not
necessarily well captured. Those with interests near streams and
smaller rivers across all of eastern Kentucky are encouraged to
monitor later forecasts and be alert for potential flood
headlines.

From Monday through Thursday, the upper level high will drift
northward to over the Mid-Mississippi Valley while the boundary
again retreats northeast. This will allow a hotter and still very
humid air mass to infiltrate our region. Disturbances riding down
the eastern side of the high will favor additional convection and
possible MCSs diving into our region from the Upper Midwest at
times. However, there should be considerable sunshine and rain-
free time as well. Heat indices could approach the Heat Advisory
threshold (105F) in the warmest spots on Tuesday and are favored
to meet or exceed criteria on Wednesday and Thursday.

Sensible weather will feature periods of showers and
thunderstorms, some with torrential downpours, through the
upcoming weekend. Isolated to scattered instances of flash flood
appear increasingly probable and could become significant in the
hardest hit locales. The most widespread rainfall is expected
during the afternoon and evening hours, but showers and
thunderstorms will remain possible during the night as well and
could still produce torrential rainfall late into the night. High
temperatures are forecast to reach mainly into the 80s through
Sunday while nights remain very muggy as temperatures only settle
back into the lower 70s. Looking ahead to the new work week,
temperatures are forecast to begin climbing a few degrees warmer
each day while humidity levels remain high. Increasingly
oppressive heat indices could flirt with 95 to 105F by Tuesday
afternoon and then warm further into the 100 to 110F range for
Wednesday and Thursday afternoons. Shower and thunderstorm chances
will linger, though coverage is expected to be less than over the
weekend.

&&

.AVIATION...(For the 18Z TAFS through 18Z Friday afternoon)
ISSUED AT 205 PM EDT THU JUL 17 2025

Isolated to scattered showers and thunderstorms continue across
eastern Kentucky this afternoon, with current flight conditions
hovering right around VFR and MVFR. Ceilings are BKN 3000 and may
drop further along with visibilities with any direct hit from a
thunderstorm through 04Z this evening. A PROB30 group has been
added through 04Z this evening at all TAF sites. A lull in
thunderstorm activity is expected from 04Z-10Z this evening, with
redevelopment thereafter. A Prob30 has been reintroduced at SYM
for this chance. In general ceilings will remain low end VFR high
end MVFR through the period. Winds will be light through the TAF
period.

&&

.JKL WATCHES/WARNINGS/ADVISORIES...
Flood Watch through Friday evening for KYZ044-050>052-058>060-
068-069-079-080-084>088-104-106>120.


&&

$$

SHORT TERM...GINNICK
LONG TERM...GEERTSON
AVIATION...GINNICK