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Area forecast discussion 
National Weather Service Jackson Kentucky
1101 am EDT Tuesday Sep 30 2014

issued at 1101 am EDT Tuesday Sep 30 2014

Most of the fog that formed during the early morning hours across
eastern Kentucky is now gone. However...current observation indicate that
some fog is still stubbornly hanging on this morning across portions
of the Cumberland and Big Sandy river valleys. A Special Weather
Statement has been issued to deal with this fog...which should be
gone by noon today if not sooner. The zone forecast text product and
hazardous weather outlook were both updated to remove mention of
dense fog for today.

Update issued at 1005 am EDT Tuesday Sep 30 2014

A number of product updates and new products were issued this
morning. The widespread dense fog that had overspread eastern
Kentucky earlier this morning has finally begun to lift and
dissipate. With the dense fog now becoming more patchy in
nature...the dense fog advisory has been cancelled. A Special
Weather Statement was issued to address any remaining locally dense
fog and any issues it may be causing in the counties that were
previously covered by the dense fog advisory. It appears the bulk of
any remaining dense fog is occurring in the Cumberland and Big Sandy
river valleys. The hazardous weather outlook was updated to reflect
the cancellation of the dense fog advisory and now mentions locally
dense fog for late this morning. The forecast grids were updated to
add in a bit more fog through 15z today to match current conditions.
The forecast and hazardous weather look products will be updated
again around 11 am to remove any further mention of fog and dense fog
for today.

Update issued at 646 am EDT Tuesday Sep 30 2014

Updated forecast to remove early morning wording. Locally dense fog
continues to plague much of southern and southeast Kentucky with most
locations reporting a quarter of a mile or less visibility. No need
to make any other changes at this time and plan to let the dense fog
advisory run its course.


Short term...(today through wednesday)
issued at 256 am EDT Tuesday Sep 30 2014

Clear skies...combined with middle level subsidence...and light
winds...has led to the development of dense fog across eastern
Kentucky this morning. This fog will continue through
daybreak...before burning off by 9 or 10 am. A fairly pleasant day is
on tap. A shortwave trough will work south across Ohio and into West
Virginia today...pushing a weak cold front southward into northern
Kentucky. The best forcing is expected to stay to our north and east
as the front just grazes our northern areas. While a few sprinkles
may be possible...models generally keep the area dry. Thus...plan to
stick with a dry forecast...although a stray shower could get fairly
close to our northern areas by late in the day. Tonight...the
shortwave will depart as the boundary stalls across eastern Kentucky.
No forcing or instability to speak will stick with the dry
forecast through tonight. Moisture pooling along the boundary could
yield another night of dense fog...especially in the river valleys
yet again. Plan to include this in the severe weather potential statement this morning. Another
pleasant day is anticipated on Wednesday as high pressure builds over
the area. Temperatures today and Wednesday will be fairly similar
with readings generally around 80 and lows tonight will fall back
into the 50s.

Long term...(wednesday night through monday)
issued at 400 am EDT Tuesday Sep 30 2014

The models are in good agreement least through the first
part of the extended. They all pump a ridge over the eastern third of
the nation in response to a digging full latitude through moving into
the plains on Thursday. This trough will approach eastern Kentucky
later that night with decent height falls and a healthy chunk of
energy. The initial portion of this energy rolls through by midday
Friday with a significant part held back over the upper Midwest. It
is this time frame...and the core of this energy...that starts to
separate the model solutions. The GFS remains the fastest of the
models swinging the trough axis and the bulk of the energy through
the Ohio Valley later Friday while the European model (ecmwf) holds its core back a
bit. The models of late have been trending toward a slower
solution...but not as extreme as the 12z European model (ecmwf). The latest version
of the over seas model seems to have backed off on its more southern
upper low for the weekend. It does still keep the lowest heights
over Kentucky when compared to the others...but the European model (ecmwf) is not as
much of an outlier as its 12z version earlier in the shift.
Nevertheless...the trough looks like it will remain anchored over
the northeastern two thirds of the nation through the weekend and
into Monday. Through it all...the European model (ecmwf) holds to its deeper solution
for the Ohio Valley. For weather details favored the European model (ecmwf) solution
through the first part of the extended followed by a general model
blend thereafter.

Sensible weather will feature a couple of warm and pleasant early
fall days before a strong cold front brings a reminder of what season
we are in later Thursday night and into Friday. With this boundary/S
arrival...showers can be expected...invading from west to east late
Thursday into the day Friday along with a slight chance for
thunderstorms. Breezy conditions will be found through the area
Thursday night...especially in the higher terrain of southeast
Kentucky. Colder air then rushes into the state Friday through
Saturday with plenty of clouds and a small chance for light rain
showers lingering into early Saturday morning...mainly in the north.
A secondary cold front will move into the area Sunday night into
Monday with a renewed shot of chilly air and a potential for light
rain showers.

The CR grid Load proved to be a good start to the extended grids...
though did adjust the probability of precipitation a tad toward the newest European model (ecmwf) solution
through the weekend. Did also tweak the low temperature grids a bit
each night to reflect at least some minor ridge and valley
differences that will probably be largest later in the forecast...
most likely on Saturday and Sunday nights.


Aviation...(for the 12z tafs through 12z Wednesday morning)
issued at 646 am EDT Tuesday Sep 30 2014

LIFR or worse conditions will continue at the taf sites through the
early morning hours before the fog lifts and Burns off by middle
morning. VFR conditions will then return to the area with mainly
clear skies and light winds expected today. The clear skies and light
winds will again set up another night of locally dense fog tonight
and have included it in the tafs yet again.


Jkl watches/warnings/advisories...


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

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