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000
FXUS63 KJKL 240318 AAB
AFDJKL

AREA FORECAST DISCUSSION...UPDATED
National Weather Service Jackson KY
1118 PM EDT Tue Apr 23 2024

.KEY MESSAGES...

- A weak passing cold front will bring light showers to most
  locations tonight into early Wednesday morning.

- Below normal temperatures return by Thursday morning, bringing
  the risk for patchy frost in valleys.

- Temperatures then trend well above normal for the weekend.

&&

.UPDATE...
-- Changed Discussion --
Issued at 1118 PM EDT TUE APR 23 2024

Showers and sprinkles were moving across the northern half of the
CWA at this time along and in advance of a cold front that is
dropping across the OH Valley. Grids were updated based on recent
observations and radar trends. This led to no substantial changes
at this time.
-- End Changed Discussion --

&&

.SHORT TERM...(This evening through Wednesday night)
Issued at 321 PM EDT TUE APR 23 2024

The afternoon surface analysis shows high pressure has settled
southeast along the Atlantic Coast of Georgia and a cold front is
advancing across the Midwest. The CAMS and ensembles are in good
agreement with this cold front pushing southward toward eastern
Kentucky later this evening into early Wednesday. Meanwhile, we
will see a mid-level spoke from the upper level closed low slide
across the Great Lakes introducing height falls to the Ohio
Valley. This will lead to a good chance of rain showers (60-90
percent), but it will only produce very light rainfall totals of
generally a tenth of an inch or less. The idea of these totals
match well with the LPMM of the HREF, with the higher totals of
around a tenth or a little more being in the far southeast. Timing
wise, the best chances of rain will be between midnight and 4 am
from northwest to southeast.

The guidance including the ensembles indicate the cold front will
pass through Wednesday and high pressure build in quickly at the
surface. This will lead to northwest flow and slightly cooler
temperatures than today, but clouds will clear quickly through the
day based on the HREF. High pressure will continue nosing into
the Lower Ohio Valley Wednesday night. This coupled with clear
skies will lead to mainly eastern valley frost potential late
Wednesday night into Thursday morning. Given this leaned toward
the previous forecast and the COOP MOS versus the 5th percentile
of the NBM. This is because the NBM 5th percentile doesn`t seem to
have a good handle on this idea. This will lead to overnight lows
in the low to mid 30s in the eastern valleys and the upper 30s to
lower 40s elsewhere.

.LONG TERM...(Thursday through Tuesday)
Issued at 352 PM EDT TUE APR 23 2024

An active meridional upper flow pattern will be in place across
the CONUS during the extended. We will see a trough of low
pressure moving into the southwestern portion of the country to
being the period, with another less developed trough pushing
onshore in the Pacific Northwest early Thursday. Further east, a
ridge of high pressure aloft will extend from the southern Plains
northward into southern Canada, with another large trough aloft
exiting the New England region, along with a ridge of surface high
pressure in place across the Great Lakes, the Ohio Valley, and
portions of western New England and the Mid-Atlantic region. The
GFS and ECMWF both were in pretty good agreement with the general
flow pattern and with the evolution of the previously mentioned
surface and upper level features.

The feature of note for our weather to begin the extended, will be
a short wave trough that will be taking shape over the east
central Plains beneath the upper ridging on Thursday. As this
system evolves and intensifies, it will move slowly north
northeast through the Plains and eventually into the western Great
Lakes to end the week and into the upcoming weekend. The surface
ridge mentioned earlier looks like it will be strong enough to
keep the Great Plains low from making much eastward progress, so
we should see minimal influence from that first system. A warm
front associated with the developing storm will move through our
area Thursday night through early Saturday, and will bring
scattered showers and a few thunderstorms to eastern Kentucky
during that time. The warm front should finally clear the area
late Saturday morning. Once this happens, a ridge of high pressure
that will be situated off the southeastern CONUS, will expand
westward just enough to keep our weather dry and quite warm
Saturday through the first half of Sunday.

The southeastern ridge should finally begin to break down Sunday
and Sunday night, as the Great Plains trough intensifies even more
and begins to finally make a more concerted eastward push. As
this occurs, we should see a surface cold front move through the
region from Sunday evening through Tuesday evening. Due to strong
shear and the major east or northeastward movement of the parent,
the surface front will be stretched from north to south and will
be very slow to dissipated and/or exit the area heading into the
first of next week. With a good supply of moisture and lift
expected to be in place for awhile, we will see very good chances
for showers and scattered thunderstorms to end the weekend and
into the first of the new work week.

Temperatures look to be quite warm and generally well above normal
through most of the extended. We should see at least a few days of
high temperatures ranging from the upper 70s to lower 80s across
our area. Before the first weather system brings extensive clouds
and rain to the area, we will see conditions conducive to a ridge
valley temperature split, with a ridge nearly overhead and very
light winds and mostly clear skies. Our normally deeper and colder
eastern valleys may even see some frost early Thursday morning.
Another ridge valley split set up will be present Friday night,
but should not be nearly as pronounced as the one the night
before. That being said, we may see a few isolated locations
experience some patchy frost early Saturday morning in our
northeastern valley areas.

In a nutshell, there are no major weather concerns in the extended
outside of the frost possibility early Thursday morning, when
frost could be widespread enough in our northeastern counties to
cause a few issues. As far as thunderstorms go, we will see some
activity, but at this time it appears that nothing strong to
severe will in our forecast for now.

&&

.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
ISSUED AT 830 PM EDT TUE APR 23 2024

Mid level clouds are gradually moving/developing south and
southeast into eastern KY ahead of an approaching cold front.
Generally VFR should prevail in all areas through around 09Z
before a few hours of MVFR occurs near the boundary in showers. However,
these lower CIGs of mostly MVFR are still expected to mix out
through the day on Wednesday between about 14Z and 18Z. Winds will
diminish as the period begins to 10KT or less and remain southwest
to west through around 12Z, before becoming northwest to north to
end the period.

&&

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

$$

UPDATE...JP
SHORT TERM...DJ
LONG TERM...AR
AVIATION...JP