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Area forecast discussion 
National Weather Service Jackson Kentucky
708 am EDT Wednesday Oct 22 2014

issued at 649 am EDT Wednesday Oct 22 2014

Forecast seems to be well on track so far this morning. Loaded in the
latest observational data into the near-term forecast to make sure
that temperatures...dew points...and winds were well reflected.
Otherwise...clouds continue to push into the region...with some lower
MVFR ceilings. Expect dry air to begin intruding from the west...effectively
cutting off the cloud cover beginning in the SW over the next few


Short term...(today through thursday)
issued at 336 am EDT Wednesday Oct 22 2014

Weather pattern during the short term will continue to be driven by
a cut off low that will sink southeast from WV to the Seaboard of Virginia and
NC by this afternoon...before transitioning to a more NE
direction...along the Atlantic coast Wednesday night and Thursday.
Eastern Kentucky will find itself on the backside of this low...with
heights expected to build through the short term forecast as a
shallow ridging pattern tries to push eastward into the region.
Moisture will continue to wrap around this low...and ride along northwest
flow into the appalachian region. This moisture will lead to
continued cloud cover across the NE/rn most portion of the County Warning Area...and
the potential for some upslope induced shower development in the far
east. Given the latest model runs the eastward progression to the
Atlantic coast today could result in enough movement to keep these
rain shower chances just along Pike County and points eastward
outside of our County Warning Area.

Meanwhile...this set up will allow for a strong pull of winds from
the north...especially in the middle and upper levels. In fact...latest
European model (ecmwf) continues to support a strong jet streak oriented from north
to south to move eastward across eastern Kentucky this morning and into
the day today. What this will translate to...besides high winds a strong pull of Canadian temperatures southwards and
into the region. Temperature forecast during the short term will be
much dependent on the cloud cover...but generally expect much cooler
than normal temperatures today...warming slightly by tomorrow..and the
potential of frost development overnight tonight.

There has been talk between the offices concerning whether or not to
go ahead and issue a frost advisory for tomorrow night. General
consensus was to pass along to the day shifts and let them decide if
one is needed or not. At this point...after adding in frost for
locations that will see temperatures 37 degrees or less...we still seem to
be a bit limited on coverage...with the best potential in the far
north...far south...and in valley locations. However...adding in
frost for areas expecting 38 degrees and under...would put much of
the area in patchy/areal coverage and matched up better with
neighboring offices. Weighing both situations...decided to stick
with including frost for areas expected to see 37 degrees or less
overnight in spite of sparser coverage...since 38 degrees seemed to
be pushing the limits of being too warm for ice to form.

Long term...(thursday night through tuesday)
issued at 417 am EDT Wednesday Oct 22 2014

Ridging at the surface and aloft should be present as the period
starts...with uneventful weather. A shortwave trough will be heading in
from the northwest...and passing over on Friday or Friday evening. Some
model runs have occasionally shown some light precipitation with this
feature...but latest runs are dry...and a dry forecast will continue
to be used. Once this moves past...we can expect benign northwest flow
aloft with dry air in place. Ridging at the surface and aloft should
once again pass east over the region during the weekend...with dry
weather continuing at least through Monday. The next cold front is
expected to be approaching Kentucky from the west or northwest late Tuesday...but
any precipitation associated with it will likely hold off until after this
forecast period.


Aviation...(for the 12z tafs through 12z Thursday morning)
issued at 706 am EDT Wednesday Oct 22 2014

A stratocu deck continues to plague eastern Kentucky under generally
northerly flow. Ceiling readings currently range from MVFR to VFR...but
per the latest observational trends...expect ceilings to remain mostly
MVFR at taf sites before forecast soundings suggest ceilings lifting
back to low end VFR by 15 to 18z. Scattering out should occur first
in the southwest /I.E. Sme and loz/ and will occur last in the far
east /I.E. Sjs/. Once drier air takes hold and skies begin
clearing...VFR conditions should be expected for the remainder of the
day under clearing skies. By tonight...soundings are showing lowering
ceilings once more...but high pressure in place should keep clouds scattered
at best. Do expect both frost and fog to develop...but most of the
fog should be limited to the river valleys and should not affect the
taf sites. As such...chose to leave the mention of fog out at this


Jkl watches/warnings/advisories...


short term...jmw
long term...hal

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