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Area forecast discussion...updated 
National Weather Service Jackson Kentucky
1035 am EDT Tuesday Sep 16 2014

issued at 1035 am EDT Tuesday Sep 16 2014

14z surface analysis shows a slow moving cold front dropping south
through eastern Kentucky. This will eventually move into Tennessee
and allow a cool and drier area of high pressure settle over the Ohio
Valley. However...the boundary continues to provide decent coverage
of light showers and sprinkles across the area. Clouds and patchy fog
complete the gloomy picture. Temperatures and dewpoints are similar
through the area ranging from the upper 50s in the far north to the
middle 60s in the south. Winds are light across east Kentucky and
generally from the northwest to north...though southwest winds are
found near the Tennessee border just south of the front. Expect a
gradual improvement in conditions through the day but the hrrr
supports the idea of a slow process with any lifting of the ceilings and
drying of the boundary layer today. As such...have kept low probability of precipitation
going for most of the area into the afternoon and limited any
clearing. Also kept a really small diurnal curve for temperatures
right through peak heating. The grids were adjusted primarily for
probability of precipitation and weather while the T/dew point where tweaked based on the latest observation...
trends...and consshort guidance. These have been sent to the ndfd and
web servers with an updated set of zones to follow shortly.

Update issued at 821 am EDT Tuesday Sep 16 2014

Light showers/drizzle are winding down across eastern Kentucky...with
the better concentration of shower activity now focused along the
Tennessee/Virginia border. Will continue to allow for a few showers/drizzle in the
wake of the cold front into this afternoon...with a gradual decrease
from northwest to southeast.


Short term...(today through wednesday)
issued at 317 am EDT Tuesday Sep 16 2014

Main action this morning remains centered around a cold front
dropping south across northern Kentucky. Isolated to scattered
showers continue to develop along and just ahead of this boundary
across eastern Kentucky. In fact...coverage of showers has continued
to expand over the past few hours. the north of the
boundary...light rain/drizzle has developed with an abundance of
shallow low level moisture. The front will continue to sag southward
through the rest of the morning and into the afternoon hours with the
threat of showers spreading southward. The drizzle threat will also
expand southward into eastern Kentucky later this morning. As the
front slides south into this afternoon...chances of precipitation
will taper off from north to south. However...clouds will be stubborn
today...and will hold down temperatures through the day. Much like
this past Saturday...going to go well below guidance on highs this
afternoon given this cloud cover combined with the ongoing cold
advection behind the exiting cold front.

Still some questions as to how much cloud cover will linger into
tonight. Models remain aggressive on clearing things out. If this is
the case...areas of fog will likely develop tonight and may become
locally dense. Going to add a mention into the severe weather potential statement for the dense fog
possibilities. After the fog Burns off Wednesday...sunshine should
return...helping temperatures rebound to around 70 for afternoon
highs after a chilly start where valleys may start the day in the
upper 40s.

Long term...(wednesday night through monday)
issued at 317 am EDT Tuesday Sep 16 2014

The models are in good agreement with an overall amplified pattern
in store for the Continental U.S. Through the extended portion of the forecast.
An upper level ridge will start out across The Rockies...with
troughing in the east and off the West Coast. These features
generally dampen out through the end of the workweek...with the
ridge flattening as it expands into the Mississippi Valley. The West
Coast trough will also weaken as it settles in across Southern
California. Meanwhile...some residual troughing setting in across
the plains will allow for a short wave trough to dive southeast out
of Canada and establish a deeper trough across the eastern Continental U.S. By
early next week...bringing another reinforcing shot of cooler air to
the region.

For eastern Kentucky...generally dry weather will continue across
the area through the first half of the weekend as we will be under
the influence of modest ridging aloft. Temperatures will be
warming through the period...with highs building back to near
seasonal normals by Friday...and likely eclipsing normals by
Saturday. By Sunday...a Stout cold front will be on our doorstep as
a deepening trough moves into the Great Lakes. There will likely be
some timing and intensity modification with this more amplified
system forthcoming from the will continue to stick close
to the blended solution. Right now...the overall best chances of
precipitation look to occur late Sunday into early Monday morning.
Temperatures will cool off to the low to middle 70s for highs by
Monday...with some 60s possible beyond that depending on the depth
of the cold air.


Aviation...(for the 12z tafs through 12z Wednesday morning)
issued at 821 am EDT Tuesday Sep 16 2014

An exiting cold front will bring IFR stratus and a few showers to
the area through early this afternoon...diminishing from northwest to
southeast. IFR stratus will lift to MVFR levels early this afternoon
before returning to VFR as clouds scatter out towards this evening.
Light north to northeasterly winds will become calm tonight...and
with clearing skies...expect at least IFR or worse fog to take hold
between 06 and 12z.


Jkl watches/warnings/advisories...


short term...kas
long term...geogerian

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