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Area forecast discussion...updated 
National Weather Service Jackson Kentucky
1055 PM EDT Friday Oct 9 2015

issued at 1055 PM EDT Friday Oct 9 2015

The surface cold front is approaching the Highway 80/hal Rogers
corridors. A few more moderate showers have developed along the
boundary as it has moved southeast. Have adjusted probability of precipitation based on
the radar trends...allowing for more scattered activity
continuing mainly along and south of the hal Rogers and Highway 80
corridors into the overnight hours...with a sharper gradient of
lesser probability of precipitation back towards the northwest. Looking upstream...there
is some partial clearing working in from northern Indiana/Ohio...
however given the north to northeast low level flow in
place...which tends to allow for a slower advection of the colder
air into our area...have adjusted some of the lows in the
Bluegrass up a bit. Updates have been sent.

Update issued at 818 PM EDT Friday Oct 9 2015

Instability has waned across eastern Kentucky...with no lightning
being seen for the past few hours in our area. The cold front has
crossed the I-64 corridor and this will continue to sag south over
the next several hours. The precipitation shield has really
diminished in areal have reduced probability of precipitation. Also freshened
up the hourly temperatures and dew points to reflect to quick cool
down that occurred with the earlier convection. Will assess the
forecast low temperatures a bit later this evening.


Short term...(this evening through Saturday night)
issued at 338 PM EDT Friday Oct 9 2015

This afternoon we have a frontal boundary that continues to
approach and move into northern portions of the region. While most
the storms have been benign...a few of these storms have become
strong at times and will have the potential to cause gusty winds
and small hail. This has been aided by good insulation this
afternoon...that allowed decent instability to build across
portions of the area. This coupled with marginal shear have been
able to see some isolated strong storms. Otherwise most spots will
see some rain this afternoon through the evening...with heavier
storms you could get upwards of half an inch or more. Otherwise
front will move across the region with winds coming back around
from the west and northwest through the afternoon and evening. In
the upper levels...the trough will lag behind and move southeast into the
Carolinas by early Saturday morning and upper level ridging will
building into the Ohio Valley and eastern Kentucky through the remainder
of the short range. Post frontal fog will also be possible tonight
with rain occurring in most locations...therefore added some
patchy dense fog to the grids to account for this. Then clearing
skies Saturday into Saturday night. These clearing skies will set
the stage for cool night with lows for Saturday night into Sunday
morning dropping into the lower 40s and maybe even a few upper 30s
particularly in the valley locations.

Overall models have had a decent handle with this front and precipitation
associated with it. Did lean toward grids already in place and
superblend at times toward the end of the period. Overall timing
was best handled by the hrrr...however overall intensity seemed to
be best handled by the arw/nmm. Temperature wise leaned away from the
warmer superblend for Saturday night given the higher temperatures and
leaned toward the GFS particularly in the valley locations.

Long term...(sunday through friday)
issued at 428 PM EDT Friday Oct 9 2015

There is good model agreement with a fairly amplified long wave
pattern to rule across the Continental U.S. For the extended portion of the
forecast. A strong short wave trough will move east across the
U.S/Canadian border...before shifting more to the northeast into
eastern Canada towards mid-week. This will carve out a broad
trough across the Great Lakes/Ohio Valley region...with several
short wave troughs to move through the area.

Sunday through Monday will feature mainly dry days across eastern
Kentucky with above normal temperatures. A cold front will be
threatening by late in the day on Monday...with a few showers to
contend with in the northwest portion of the area. The best chance
of rain for the entire area will arrive Monday night as the
boundary moves through the region. A fairly transient cooler air
mass will follow for mid-week...with temperatures back down closer
to seasonal values. Another front will approach the area by
Friday...however it looks pretty moisture maintained
dry weather...similar to the blended guidance. A more significant
cool down could follow this front into next weekend.


Aviation...(for the 00z tafs through 00z Saturday evening)
issued at 818 PM EDT Friday Oct 9 2015

Ceilings will generally be lowering as a cold front sags south
across eastern Kentucky. Any remaining VFR conditions in the south
will be dropping down to MVFR and IFR through the night as cooler
air moves in. Isolated to scattered rain showers will also be
around through the night...with a general diminishment in areal
coverage by dawn. A return to VFR conditions is expected by the
late morning/early afternoon hours on Saturday as high pressure
starts to build in across the area. North to northeast winds at 5
to 10 kts...with a few gusts to around 15 kts initially following
the frontal passage...will gradually diminish to around 5 kts or
less through the period.


Jkl watches/warnings/advisories...


long term...geogerian

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