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Area forecast discussion...updated 
National Weather Service Jackson Kentucky
1205 PM EST Monday Jan 26 2015

issued at 1155 am EST Monday Jan 26 2015

The band of steadier snow continues to work across the southeastern
counties with some light snow and flurries on upslope flow/instability
lingering behind this. Some of this lighter snow and flurries are
below the radar the areal extent at this time may be a bit
greater than indicated by radar. The temperatures are generally
running below guidance once the colder air moves in and we currently
expect temperatures to recover only a degree or two the remainder of
the nearly steady temperatures are expected in most
places...with a bump down in the deepest valleys in the far southeast
and then nearly steady for the rest of the day.

Northwest flow an additional disturbances passing by will lead to
isolated to scattered snow showers and flurries through at least
tonight. Additional snow accumulations will be light generally less
than a half of an inch. However...the nearly steady temperatures
below freezing and some light falling precipitation should act to cool
roadways and surfaces and slick or refreeze spots are anticipated at
times especially on any untreated locations. These could become more
prevalent by dark...depending on where snow showers and flurries
occur. An Special Weather Statement has been reissued to handle this and graphical nowcasts
will continue to be issued this afternoon to address this.

Update issued at 647 am EST Monday Jan 26 2015

WSR-88D radar shows a few showers and snow showers moving across the
region the morning as clipper low continues to progress across
eastern Kentucky. The temperatures have been tricky overnight into this
morning as colder air continues to slowly advect from northwest to southeast this
morning. Freshened up grids with latest observation and trends this morning
including a quick update of weather grids to better show transition this


Short term...(today through tuesday)
issued at 342 am EST Monday Jan 26 2015

WSR-88D this morning has continued to show areas of rain showers
moving across eastern Kentucky this morning. Best coverage has generally
been across the far southern portions of the region this morning.
However this morning we have seen generally lower amts of precipitation and
temperatures are still above freezing at most locations beside Black Mountain at
8z. Given this have lessen probability of precipitation and also lessened quantitative precipitation forecast amts across the
region. This may still be too optimistic as returns from radar have
been quite low across central and western Kentucky this morning. This trend
of lowering reflectivities is also back up by the hrrr which also
initialized fairly well at 7z. Otherwise left over showers will slowly
transition to snow showers through the day with best coverage across
the far east this afternoon.

This surface low and upper level trough will continue exit east where
it develops into a strong noreaster along the Atlantic Seaboard later
today. Across eastern Kentucky we will continue to transition to generally
west to northwest flow. Models do show a fetch of moisture dropping south
from the Great Lakes tonight into Tuesday. Right now have moved
toward slight chances of snow showers mainly across SW portion of the
County Warning Area where better placement of moisture axis exists. Even so generally
mostly cloudy conditions will prevail for much of the period area
wide coupled with generally below normal temperatures.

Long term...(tuesday night through sunday)
issued at 445 am EST Monday Jan 26 2015

The models are in good agreement aloft for the first part of the
extended and are in fair agreement with the latter part. The rub here
is that the consistency has been taking hits lately with the forecast
for next weekend. A once discarded solution...mainly seen earlier in
the GFS...has returned with some limited support from the European model (ecmwf).
Early on...the focus will be on a deep cyclone off the eastern
Seaboard while a fast flow of energy roils above east Kentucky on a
generally northwest to southeast path into Wednesday morning. This
vorticity stream is shunted east by midday Wednesday as higher heights
from a weakening southern ridge moves into the middle Mississippi
Valley and then over the lower Ohio basin. At the same time...a
developing trough will dip into the Central Plains and slide east.
This feature ramps up into the day Thursday with the GFS providing
better support for the more robust solution of the European model (ecmwf). This
trough crosses east Kentucky later Thursday night with flat flow to
follow. However...over the southwest parts of the nation a large
closed low in the southern stream is now depicted...particularly by
the latest European model (ecmwf)...opening up and spilling its energy east into the
flow riding over the Tennessee Valley. The models now show some
connection to the northern and southern streams which would certainly
make things more interesting for the upcoming weekend if that pans
out. For now...will show only limited interaction and ease into a
more dynamic scenario given the uncertainty and lack of model run to
run consistency with this part of the forecast. In general...a blend
of the models was preferred through the bulk of the forecast with
some adjustment toward the previous forecast for next weekend given
the consistency concerns.

Sensible weather will feature the ending of the upslope snow
showers/flurries in the far east early Wednesday morning with some
sunshine returning. The next clipper system will then move into the
Ohio Valley on Thursday with a chance for rain and snow across the
area into Friday morning. Only a brief window for drying can be
expected from Friday night into Saturday morning before the potential
for mainly snow arrives from the southwest in fast low and middle level
flow riding along a west to east Arctic boundary lying over the Ohio
Valley. This boundary is expected to push on through Kentucky by
Sunday morning with snow chances continuing...mainly in the southern
parts of the County Warning Area. This setup will need to be watched closely... the potential exists for the cold air to settle into the
state by late in the weekend and a low to form in the northern Gulf
sliding northeast while sending ample moisture north into our area
on the cold side of this Arctic boundary. For now...have gone with
just small chances for snow from Saturday afternoon through Sunday...
but that will surely need to be adjusted one way or another as the
models get a better handle on this situation in future runs.

The CR grid Load made for an okay start to the extended forecast
grids with changes made primarily to better reflect the latest European model (ecmwf)
solution for the upcoming weekend. Also...made some typical ridge
and valley temperature adjustments for lows each night.


Aviation...(for the 12z tafs through 12z Tuesday morning)
issued at 632 am EST Monday Jan 26 2015

Most sites have come down this morning to IFR and LIFR conditions. A
few sites are seeing lower visible due to fog and/or shower activity moving
across those sites. Colder air is slowing moving into the region this
morning and will transition rain showers to snow showers as we go
through the morning. Otherwise a few sites are seeing gusty winds
around 15 to 20 kts as winds begin switching west to northwest
through the day as low continues to exit to the east. Otherwise sites
are expected to improve later this afternoon as drier air continues
to filter into eastern Kentucky.


Jkl watches/warnings/advisories...

long term...greif

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