Somerset, Kentucky 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

454
FXUS63 KJKL 170020 AAA
AFDJKL

AREA FORECAST DISCUSSION...UPDATED
National Weather Service Jackson KY
820 PM EDT Thu Jul 16 2026

.KEY MESSAGES...

- Hot and humid weather continues through Friday, with widespread
  heat indices in the 90s to near 100 degrees.

- An anomalously moist airmass arrives in western portions of the
  CWA this evening, then expands area-wide this weekend.

- Expect daily rounds of storms through Saturday, some of which
  could produce heavy rainfall and localized flooding.

- A series of cold front will cross the region early next week,
  bringing another round of thunderstorms to the area on Tuesday
  and then relatively cooler and drier weather towards mid-week.

&&

.UPDATE...
Issued at 735 PM EDT THU JUL 16 2026

23Z sfc analysis shows high pressure west of the state with a dome
of high heights over eastern Kentucky. This is keeping most of
the area free of convection except for some pinprick cells that
are nearly stationary providing a scant few locations a narrow
bout of heavy rain. The worst so far has been over central
Jackson County where there was some small response in the creeks
per the CREST analysis, but that cell has since dissipated.
Otherwise, the activity fades out with sunset allowing for mostly
clear skies and the development of fog in the valleys becoming
locally dense - especially for spots that saw any rain today.
Currently, temperatures are running in the still very warm low to
mid 80s. Meanwhile, amid light and variable winds, dewpoints
remain quite high in the low to mid 70s most places. Have updated
the forecast mainly to add in the latest obs and trends for the
T/Td/Sky grids. These minor adjustments have been sent to the NDFD
and web servers along with a freshening of the SAFs and zones.

&&

.SHORT TERM...(This evening through Friday night)
Issued at 420 PM EDT Thu Jul 16 2026

Today`s forecast guidance suite continues to resolve the breakdown
of the elongated ridging circulation responsible for the warm, but
relatively drier, conditions observed across the forecast area
earlier this week. As it does so, synoptic subsidence will weaken
and greater amounts of low-level moisture will return to the column
via west-southwesterly flow around the periphery of the remnant high
centered over the Gulf Coast states. The effects of this subtle
pattern shift are multi-faceted. First, the related increase in
humidity has allowed heat indices to climb into the 90s across much
of Eastern Kentucky this afternoon. A few locales (mostly urbanized
areas in the western portions of our CWA) could record apparent
temperatures in the triple digits, but widespread heat-related
impacts are not expected. This is due to the second effect of the
increased atmospheric moisture -- deeper and more widespread diurnal
cumulus clouds.

Isolated to scattered showers are noted in radar imagery across the
western half of the CWA this afternoon, but the convective activity
thus far has struggled to strengthen into thunderstorms. This is
likely due to the lack of well-defined forcing and wind shear in
today`s set up, but that also means that any taller updrafts will
likely be slow-moving and prone to produce outflow boundaries. The
best chances for more meaningful convection are in our Lake
Cumberland counties, where 19z Mesoanalysis reveals 2000-3000 J/kg
of CAPE and PWATs around 1.8 inches. Thus, we will need to closely
monitor convective trends in southwestern portions of the CWA
through this evening. The 12z HREF LPMM data painted a couple of QPF
bullseyes in this region, and while widespread hydrological impacts
are not expected, minor flooding cannot be ruled out. WPC has
introduced a Marginal (Level 1/4) Excessive Rainfall Outlook in this
region, which seems reasonable given those mesoanalysis parameters.

Aside from a few late attempts at additional updrafts atop residual
outflow boundaries, most of the late afternoon and early evening
convective activity should subside after sunset today. Once it does
so and the lingering cloud debris fizzles out, expect modest ridge-
valley temperature splits and radiation fog formation overnight. It
is plausible that that leftover cloud cover could prevent true
ground fog from occurring, but given the potential for localized
pockets of wet grounds and the higher amounts of boundary-layer
moisture present, relatively greater spatial coverage of patchy fog
was maintained in tonight`s forecast grids. Areal coverage was
contained to the river valleys, and visibility trends will need to
be monitored in area observations. Tonight`s greater fog potential
is the third effect of the shift to a wetter late-week pattern, and
interests with early AM travel plans (and those who are not
necessarily accustomed to driving in the fog) are encouraged to
exercise caution and monitor for any fog-related product issuances.

Similarly hot temperatures will overlap with even greater amounts of
moisture over the forecast area tomorrow. This will allow more
widespread heat indices in the mid/upper 90s, and a larger portion
of the forecast area could approach the triple digits. Expect
convection coverage to accordingly increase to the scattered to
numerous range through, which will once again provide some localized
relief from the heat. Widespread severe weather is unlikely, but any
storms that develop tomorrow are likely to be water-loaded. The HREF
resolves mean PWATs increasing into the 1.9-2.1" range alongside
2000+ J/kg of SB-CAPE across the entire CWA tomorrow afternoon. Bulk
shear remains weak (generally less than 20 knots) and the primary
lifting mechanisms will once again be convection. With all of the
above in place, tomorrow`s storms will need to be monitored for
gusty winds (via wet downbursts and outflow boundaries) and
torrential downpours. Storms are poised to be slow-moving once
again, and if outflow boundaries act as a secondary lifting
mechanism, multiple rounds of storms could affect the same small
stream basins. As such, WPC has outlined the entirety of the
forecast area in a Marginal (Level 1/4) Rainfall Outlook tomorrow.
If tonight`s risk materializes, a corridor of greater flash flooding
could emerge tomorrow. So, interests are encouraged to remain
weather aware for the next 36 hours and have multiple (reliable)
ways to receive weather updates and warnings.

.LONG TERM...(Saturday through Thursday)
Issued at 400 PM EDT Thu Jul 16 2026

A wave will be rotating through a northeast CONUS trough at the
start of the period, bringing a temporary deepening of the trough
southwestward over the Ohio Valley. It will support a cold front
which will be over the Great Lakes/upper Midwest early Saturday. The
approaching front will result in WSW low level flow carrying very
moist air over our area. A fair amount of deep moisture should also
be present with the approach of the wave, with PWs near 2". The
scenario favors showers/thunderstorms with locally heavy rainfall
where they are persistent. Will look for a typical summertime
diurnal peak in the late afternoon/evening on Saturday, but with a
potential persisting along and ahead of the front beyond that time.
Models are still varying with timing of fropa, showing it sometime
Saturday night or Sunday. After fropa, enough drying should occur
(especially aloft) to greatly restrict or eliminate the POP Sunday
night and Monday as the northeast CONUS trough temporarily weakens
and geopotential height rises occur.

Another wave will again deepen the northeast CONUS upper trough and
support a more significant cold front to approach on Tuesday. With
this, a set-up very similar to the previous wave should evolve, with
showers/thunderstorms making a comeback. The GFS and ECMWF vary on
timing of fropa - either Tuesday night or Wednesday. Behind the
front, more significant drying is expected at midweek.

&&

.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
ISSUED AT 820 PM EDT THU JUL 16 2026

Currently, VFR conditions prevail at all the TAF sites for the
start of the 00Z aviation cycle. Locally wet grounds and an
overall increase in low-level moisture relative to Thursday keeps
confidence fairly high for greater fog coverage tonight than last.
KSME and KLOZ are the most likely to fog in, so more significant
vsby reductions have been explicitly included there into dawn,
Friday. Elsewhere, TEMPOs cover the potential for patchier fog.
Once the fog lifts, expect another day of generally scattered
showers and storms, this time with wider spatial coverage.
Convection chances begin to increase at the latter portion of the
period, especially for the western terminals. Outside of any
showers and storms, expect generally light winds - adopting more
of a southwesterly orientation on Friday.

&&

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

&&

$$

UPDATE...GREIF
SHORT TERM...MARCUS
LONG TERM...HAL
AVIATION...MARCUS/GREIF