Area Forecast Discussion
Issued by NWS Jackson, KY

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FXUS63 KJKL 300815

Area Forecast Discussion
National Weather Service Jackson KY
415 AM EDT MON MAY 30 2016

.SHORT TERM...(Today through Tuesday)
Issued at 405 AM EDT MON MAY 30 2016

07z SFC analysis shows a weak cold front setting through Central
Kentucky. A cluster of more organized storms were spawned by the
front and affected the I-64 corridor earlier in the night with
heavy rains and a potential for flooding. A few of these advisory
and warning products remain in effect over Fleming and Rowan
Counties, but if trends hold they should be allowed to expire on
time. Elsewhere, the approach of the front has triggered more
isolated cells of convection south of I-64. Expect these to
gradually wane in time as they trek east through the CWA. The
front, convection, and clouds are keeping the valley fog in the
patchy range for most places in the western 2/3rds of east
Kentucky that report obs. Skies are clear to the east, though, and
some dense fog is being reported closer to the Virginia border.
Meanwhile, temperature differences have mostly mixed out with the
front`s arrival, except in the far southeast where they still vary
from the mid 60s on ridges and near 60 degrees in the deeper
valleys. Dewpoints remain in the muggy category across the CWA,
generally within a degree of dry bulb temps - in the low to mid
60s. Outside of any localized shower or storm, winds are light
and variable across the area at this hour.

The models are in good agreement aloft through the short term
portion of the forecast. They all depict rather flat and slow flow
at mid levels through Kentucky with just a few weakening patches
of energy passing by. This should allow SFC features to dominate
the weather pattern and keep things rather benign after the front
passes this morning. As such, have favored the higher resolution
HRRR and NAM12 for weather details through Tuesday.

This Memorial Day will feature some early morning showers and
thunderstorms around through dawn, but likely fading out shortly
thereafter as they depart to the east. Additionally, patchy dense
fog can be anticipated over southeastern parts of the CWA, unless
disrupted by a stray shower or storm. For this reason, will go
with a pre-first period zone issuance to capture the activity
through dawn. All this extra weather clears up quickly after
sunrise with partly to mostly sunny skies, pleasant conditions,
and somewhat lower humidity expected. Cannot completely rule out a
stay storm or shower right along the Virginia border during peak
heating thanks to the still lingering front, but for gridded
forecast purposes have kept it dry. For tonight, patchy valley fog
is the main wx concern as conditions may not be so muggy and a
small ridge to valley temperature split develops. Similarly nice
weather follows for Tuesday under the tenuous influence of weak
high pressure.

Once again used the ShortBlend and CONSShort as a starting point
for most of the weather elements with small to moderate
adjustments made to temperatures at night for ridge to valley
splits. Also, upped temps a notch today and Tuesday, per the
recent trends. As for PoPs, ended up similarly low with all
guidance, outside of the pre-dawn hours this morning.

.LONG TERM...(Tuesday night through Sunday)
Issued at 410 AM EDT MON MAY 30 2016

A northern stream trough and low pressure system over the northern
plains will make its way east towards the Great Lakes Wednesday
morning. This system will drag a cold front across Kentucky Thursday
but then get a bit hung up over the area on Friday. Unlike previous
runs, the models now show the front pushing southeast out of the
region by Saturday morning. This means that the weekend looks a bit
drier than in previous runs.

Shower and thunderstorm chances will be at play, however, from
Wednesday afternoon through Friday night. There will be little
forcing on Wednesday afternoon so thinking that any shower
activity will be contained to the higher terrain. Showers and
thunderstorms should be more widespread and stronger along and
ahead of the cold front on Thursday. Models indicate plenty of
instability in place for strong to severe storms but shear appears
to be lacking. So will have to keep an eye on this as the week
progresses. There will also be chances for thunderstorms on Friday
mainly along the frontal boundary but positioning is still
uncertain at this time. If the front does push out of the area
Friday night then most locations should be dry on Saturday. Shower
chances increase again on Sunday afternoon as the upper level
trough over the Great Lakes deepens, sending plenty of energy into
our area.

Temperatures will start out in the low to mid 80s on Wednesday and
Thursday. Behind the cold frontal passage, cooler and less humid air
will infiltrate East Kentucky, helping to drop high temperatures
into the mid 70s for the remainder of the period. Morning lows are
expected to remain mild, in the low 60s, through the period.


.AVIATION...(For the 06Z TAFS through 06Z Monday night)

Scattered to numerous showers and thunderstorms will continue to
threaten the northern portion of the area through 09z as a weak
cold front passes through. Following the front, and in some cases
in the valleys ahead of it, fog will form, likely becoming dense
in the deeper valleys as well as across locations that saw more
significant rainfall. Have included a period of MVFR conditions
for most TAF locations, generally between 09 and 13z. Once the
fog dissipates, VFR conditions will return. Light and variable
winds will become northerly at 5 to 10 kts on Memorial Day.


.JKL Watches/Warnings/Advisories...


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