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Area forecast discussion...updated 
National Weather Service Jackson Kentucky
741 PM EST Tuesday Dec 1 2015

issued at 735 PM EST Tuesday Dec 1 2015

A cold front has reached the Virginia border counties...but precipitation
lingers in its vicinity. On additional surface wave is expected to
lift northeast through early on Tuesday and this will bring
continued chances for showers especially across the central and
southeast County Warning Area. Locations across the Bluegrass region will likely
remain dry. Based on recent radar trends and short term model
guidance has opted to increase chances for measurable rain across
the central and southeast County Warning Area during the first 6 to 8 hours of the
period as well as sky cover. Recent hrrr and other model runs were
a tad higher with quantitative precipitation forecast across this area as quantitative precipitation forecast across the
central and east was increase a tenth or so. Otherwise...hourly
trends were freshened up based on recent observations...but this
led to no substantial change.


Short term...(this evening through Wednesday night)
issued at 355 PM EST Tuesday Dec 1 2015

20z surface analysis shows a cold front settling over far eastern
Kentucky with showers affecting the County Warning Area both along and behind this
boundary. Temperatures vary with the frontal position as cooler
air is pouring in on west winds for western parts of the area
while warmth remains in the far east. Specifically...temperatures
vary from the lower 50s in the west to the lower 60s near the
Virginia border. Dewpoints likewise vary with the temperature
within a degree or two of the dry bulb values. Winds are from the
south to southwest for the eastern parts of the County Warning Area while they are
more westerly to the west running at 5 to 10 miles per hour with occasional
gusts to 15 or 20 miles per hour.

The models are in good agreement aloft through the short term as
they all take a fairly deep...and compact...low through the upper
Midwest and into the Great Lakes during the period. The core of
this lows energy does target the lower parts of the Ohio Valley
as it moves by later Wednesday. Given the model agreement have
favored the higher resolution guidance from the nam12 and hrrr
through the short term portion of the forecast.

Sensible weather will feature showers continuing to affect the far
eastern part of the area along that stalled front. To the west
light showers and sprinkles will be found. The drier air moves
into the western parts of eastern Kentucky tonight into Wednesday
ending any accumulating rains...though fog and low clouds will
remain into the morning. the east the showers will
linger well into the day Wednesday. Additionally...a secondary
cold front will move into the area on Wednesday evening and
overnight bringing a potential for sprinkles or flurries to at
least northern parts of the area. The air will dry out throughout
the state by dawn Thursday. Colder air will gradually filter into
the area through Wednesday with a bigger surge that night for lows
back to near freezing by dawn Thursday.

Used the shortblend as a starting point for the T and dew point grids
into Wednesday morning and the superblend thereafter. From this
made some minor...terrain based...adjustments to the low
temperatures tonight and Wednesday night. As for probability of precipitation ended up
similar to MOS blend for tonight and Wednesday the on the high
side by a tad for Wednesday night.

Long term...(thursday through tuesday)
issued at 215 PM EST Tuesday Dec 1 2015

An extended stretch of dry weather is expected for the entire
extended period as a ridge builds in overhead and remains nearly
stationary through the upcoming weekend. With precipitable waters around 0.15
through the weekend...we will likely see some large diurnal ranges
each day with cold mornings and mild afternoons with highs likely
reaching above model guidance each day and possibly under guidance
at night. Next chance of rain may come sometime around next
Tuesday...although given the pattern going into Tuesday...not
willing to bite on this system yet.


Aviation...(for the 00z tafs through 00z Wednesday evening)
issued at 725 PM EST Tuesday Dec 1 2015

With a cold front slowly working across the region...MVFR to IFR
conditions should prevail along with some fog...drizzle or showers
for much of the first 12 to 15 hours of the period. Ceilings will be
near or below Airport mins in some cases for locations in closer
proximity to the front. The ceilings and visible should improve to MVFR or
VFR between 13z to 20z as high pressure and drier air build into
the state. an upper level trough axis approaches...
stratocu should approach or move into the area near the end of the
period with some locations returning to MVFR. Winds will generally
be west southwest to west northwest through the period...and
average 10kt or less in most locations.


Jkl watches/warnings/advisories...

short term...greif
long term...kas

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