785
FXUS63 KJKL 012022
AFDJKL

AREA FORECAST DISCUSSION
National Weather Service Jackson KY
422 PM EDT Mon Jul 1 2024

.KEY MESSAGES...

- Temperatures 5 to 10 degrees below normal will continue through
  tonight, before temperatures warm to near or slightly above
  normal on Tuesday.

- Humidity will increase through midweek and Afternoon heat
  indices may approach 100 in some locations Wednesday through
  Friday

- The potential for showers and thunderstorms returns by Thursday,
  Independence Day, and lasts through the weekend. The highest
  probability of rain is on Thursday and Friday.

&&

.SHORT TERM...(This evening through Tuesday night)
Issued at 410 PM EDT MON JUL 1 2024

Late this afternoon, an upper level ridge extended from portions
of the Southern Plains/Arklatex region northeast into the mid MS
Valley to Great Lakes regions. Meanwhile, an upper level trough
axis extended from western Canada across MT and portions of the
Northern Rockies into southwest Conus. At the surface, a ridge of
high pressure extended from the Great Lakes to the OH Valley to
Arklatex regions. Behind the front that crossed the region on
Sunday, the high has ushered in a cooler and drier airmass and
only a few passing cirrus were moving across the region at
present. Highs so far today have been 5 to 10 degrees below normal
for early July.

Tonight and Tuesday, the upper level ridge is expected to build
across the Southeastern Conus with the axis of the 500 mb ridge
remaining west of eastern KY. However, the sfc high pressure ridge
will slide to the eastern seaboard through Tuesday evening.
Meanwhile, the trough extending across the western Conus at
present will move east into the upper MS Valley to Plains region
to the south of an upper level low that evolves from Saskatchewan
and into Manitoba to far western Ontario. Tuesday night, the axis
of the ridge will gradually shift to the east of the area as the
upper low reaches the northern Ontario/James Bay vicinity and an
associated shortwave trough reaches the western Great Lakes to mid
MS Valley areas. The cold front associated with this system will
remain well northwest of the area through the short term period.

The high shifting east across the Great Lakes and the OH Valley
region tonight, will lead to another night with low temperatures
on the order of 5 to 10 degrees below normal. As this high moves
further east on Tuesday, return flow will begin to usher a warmer
and more moist airmass into eastern KY. PW is forecast to rise
from present levels of below 0.50 inches to about 0.65 inches in
the southeast to around 1 inch near Lake Cumberland near dawn on
Tuesday per the HREF mean and then further to around 0.9 to 1
inch east and southeast to about 1.3 near Lake Cumberland on
Tuesday evening followed by an increase to 1 to 1.3 inches
areawide by late Tuesday night.

The pattern will favor a moderate ridge/valley temperature split
with afternoon min dewpoints in the upper 40s to low 50s
supporting some lows in eastern and northeastern valleys in the
low 50s with a 49 or so in some of the typical cold spots. Fog
should also form not long after midnight along the larger creeks
and especially portions of the Big Sandy and Kentucky Rivers as
well as lakes in those basins. Temperatures will warm up nearly 10
degrees from what has been observed so far today on Tuesday with
some fair weather cumulus probable by the afternoon as moisture
increases. Any cumulus that develops on Tuesday should dissipate
by sunset on Tuesday evening and with the upper ridge axis working
across the area yet another ridge/valley split should occur with
a lesser magnitude than tonight. Valley fog should again occur,
but may be more confined to right along the rivers.

.LONG TERM...(Wednesday through Monday)
Issued at 420 PM EDT MON JUL 1 2024

The long term discussion will be issued shortly.
00
&&

.AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon)
ISSUED AT 214 PM EDT MON JUL 1 2024

Surface and upper level high pressure will result in VFR prevailing
through the period. The exception will be during the 05Z and 13Z
timeframe, where MVFR and IFR and perhaps locally lower
reductions are possible in valley fog. This valley fog is not
expected to affect the TAF sites however. Winds will be generally
be from the northeast at generally less than 10KT through 23Z,
before becoming 5KT or less for the remainder of the period.

&&

.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...JP
LONG TERM...RAY
AVIATION...JP