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Area forecast discussion 
National Weather Service Jackson Kentucky
438 PM EST Monday Feb 8 2016

Short term...(this evening through Tuesday night)
issued at 437 PM EST Monday Feb 8 2016

A relative lull in showers was making its way east across the
region late this afternoon. A greater concentration of showers was
making its way in from the west. The showers were mixed rain and
snow...with the snow more likely in the heavier precipitation. As
temperatures fall early this evening...precipitation will become
all snow and bring lasting accumulation.

Models are in agreement for the short term period. A nearly
stacked low pressure system will move east across the Great Lakes.
It will bring deep moisture with upslope flow in cold air
advection across the Great Lakes...with these factors resulting a
prolonged period of light snow and snow showers. Aside from some
of the brief heavier snow showers...accumulation rates will not be
exceptional...but over the course of time...most areas will see 1
to 4 inches of snow. The lowest amounts will generally be in the
southwest...and the greatest in the northeast and at high
elevations in the southeast. A few of the higher elevations in the
southeast could see localized amounts around 6 inches.

As the upper level low start to weaken and the system lifts out to
the northeast...snow will start to taper off from southwest to
northeast on Tuesday night.

Long term...(wednesday through monday)
issued at 437 PM EST Monday Feb 8 2016

Broad cyclonic flow will begin pulling east through the first part
of the period. This will keep snow showers and flurries in the
forecast for a good portion of eastern Kentucky. The flow will also have a
chance of tapping into some moisture from the Great Lakes for a
period of this time. Snow showers are expected to taper from west to
east though the day on Wednesday into Wednesday night...as Canadian
high pressure noses in from the northwest. While barrage of snow
showers comes to a end we are still looking at cold temperatures
with lows dropping into the teens and single digits...highs will not
make it above freezing through at least Thursday. We see more
disagreements model wise by the end of the week...and this will lead
to more forecast uncertainty in relation to upper level disturbance
for Friday and Friday night. The 12z European model (ecmwf) is much more robust with
this upper level wave bringing more substantial precipitation and a better
potential for accumulating snow...however will say it has backed off
some from the previous 00z run in relation to quantitative precipitation forecast. The GFS is on the
other extreme and keeps it dry. Right now given the uncertainty will
stick to the model blend and this does put chance probability of precipitation in the
forecast. Behind this another very strong surface high and base of
upper level low moves south and east into the region this
weekend...while the models disagree on the exact placement of the
high 850 mb temperatures look drop into the negative 20 range. Right now
looks reasonable to have temperatures easily dropping into the single digits
Saturday night. Another system looks to drop south early next
week...right now will stick with blend through this period as well.
That will bring at least chance probability of precipitation across eastern Kentucky on Monday.

&&

Aviation...(for the 18z tafs through 18z Tuesday afternoon)
issued at 121 PM EST Monday Feb 8 2016

A band of convective precipitation is passing eastward through the
region early this afternoon...bringing a quick drop to IFR
conditions in snow. East of this band...conditions were generally
VFR. Additional snow showers will develop late in the day and
this evening...and then continue at times through the end of the
period. This will create MVFR conditions...and IFR at
times...lasting through the end of the period.

&&

Jkl watches/warnings/advisories...

Winter Weather Advisory until 6 PM EST Tuesday for kyz044-
050>052-058>060-068-069-079-080-083>086-111-114-116.

Winter Weather Advisory until 6 am EST Wednesday for kyz088-118-
120.

Winter Weather Advisory until 6 am EST Wednesday for kyz104-
106>110-112-113-115-117-119.

Winter Weather Advisory until 6 PM EST Tuesday for kyz087.

&&

$$

Short term...hal
long term...dj
aviation...hal

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