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Area forecast discussion...updated 
National Weather Service Jackson Kentucky
1045 PM EST Thursday Dec 25 2014

issued at 1045 PM EST Thursday Dec 25 2014

The forecast remains on track through the rest of the night so have
just touched up the hourly T and dew point grids per the latest observation and
trends. These updated grids have been sent to the ndfd and web

Update issued at 710 PM EST Thursday Dec 25 2014

23z surface analysis shows high pressure building into eastern Kentucky
from the southwest. This has helped to clear the sky and provide for
light winds. With these conditions would expect a good night of
radiational cooling and some decent ridge to valley differences. This
is already taking place with some most sheltered valleys around
freezing while the rest of the area has temperatures in the middle
and upper 30s. Have tweaked the current forecast to emphasize this
development while reducing sky cover through the night. The updated
grids have been sent to the ndfd and web servers with an updated zone forecast product
to follow shortly.


Short term...(this evening through Friday night)
issued at 250 PM EST Thursday Dec 25 2014

Light drizzle and flurries have ended across the area and stratocu
deck is eroding quickly from the southwest. Skies will continue to
clear through the late afternoon and early evening. High pressure
just to our east will keep our weather fair through the short term
though middle and high level clouds will generally be on the increase
with time. Also expecting temperatures to rebound quickly through
the short term as winds at the surface and aloft continue to back to the
southwest. Highs Friday appear to be at least 10 degrees warmer than
todays. But night time temperatures and in particular the valley lows
will be quite chilly...settling to near normal levels.

Long term...(saturday through thursday)
issued at 354 PM EST Thursday Dec 25 2014

The weather pattern for the extended forecast period looks to be
quite active with a strong upper level short wave trough bearing
down on eastern Kentucky on Saturday. This elongated trough will
have a southern portion of energy dive south to the Gulf Coast as
the northern portion shifts to the northeast. The trough then begins
to weaken and shoots out into the Atlantic by Tuesday as the
pattern over the entire Continental U.S. Becomes zonal with a new closed low
moving south from the Pacific northwest and becomes cut off into the
Southern California region. This closed low opens and finally ejects east
out of the Baja California region into the Southern Plains.

The beginning of the extended seems to have the models in fairly
good agreement. With the initial system Saturday and Sunday.
However...the end of the extended is quite a bit murky. Surface low
pressure will track northeast into the Great Lakes with a weakening
cold front as it moves across the Ohio Valley providing a chance of
rain into the area. The seems to stall along the appalachian chain
while a second low pressure develops over the lower MS River Valley
and tracks northeast. This will provide and extended period of
rainfall over the area from Saturday through Monday. As the colder
air wraps in behind...some of the higher locations may see a change
to snow but this will not last long as the bulk of the moisture
exits. So not expecting any accumulation. With surface centered high
pressure over the Midwest and nudging into the Ohio
extended period of dry weather will then move over the region. The
mentioned closed low in the upper levels moves along the southern
stream of the jet into the Gulf Coast where surface low pressure
develops and tracks northeast. This scenario is where the GFS and
Euro are quite different with the Euro being warm and the GFS being
cooler. Though the pattern at the end of the extended and into the
first few days of the New Year...with a couple of systems moving
northeast out of Gulf of Mexico...does merit some watching.


Aviation...(for the 00z tafs through 00z Friday evening)
issued at 700 PM EST Thursday Dec 25 2014

Skies have cleared through all of the area except the far north. Up
there a layer of just inside MVFR clouds are found affecting sym.
Even here expect clear skies to take over during the next couple of
hours leaving VFR and sky clear conditions behind into Friday. Winds will
be light and generally from the south to southwest through the


Jkl watches/warnings/advisories...


short term...ray
long term...shallenberger

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