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Area forecast discussion 
National Weather Service Jackson Kentucky
735 PM EDT Thu Oct 20 2016

issued at 735 PM EDT Thursday Oct 20 2016

A challenging forecast on tap for this evening and tonight, due to
the erratic nature of the ongoing convection. Showers and storms
across eastern Kentucky have varied from isolated to numerous in
nature since this afternoon. At this time a consolidated line of
showers and storms is moving into our western tiers of counties.
The individual cells are moving from southwest to northeast, while
the line overall is moving slowly eastward. The storms are quickly
losing their punch now that the sun is down. Trend is expected to
continue for the next several hours. The activity has begun to
fill in a bit over the past hour or so, so it does appear that
most locations across eastern Kentucky will receive measurable
rainfall this evening. Once the thunder dies out, quite a few rain
showers will be left over. These will continue to move across the
area tonight through late Friday morning. The forecast in general
is on track, so no major changes are planned at this time. The
only change that was made was to ingest the latest obs into the
hourly forecast grids to establish new trends. Will likely issue
an update near the end of the shift to remove evening wording from
the zone forecast text produce, and to remove mention of thunder
if necessary.


Short term...(this evening through Friday night)
issued at 352 PM EDT Thursday Oct 20 2016

Shower activity continues to develop across the area this
afternoon with a few thunderstorms thrown in for good measure.
Have been seeing some gusty winds with the stronger and more
organized thunderstorms, generally up to 25 mph but would expect
a few places are seeing gusts to around 30 mph. Have also received
a couple reports of small hail, anywhere from pea to nickel in

Sfc low pressure is getting more organized now and is currently
moving through the commonwealth. A cold front will be pulled
through the area this evening as the low continues to track off
to the northeast tonight. We still expect around three quarters of
an inch of total rainfall across much of the area on average from
this afternoon through Friday morning. Showers will taper off
pretty quickly Friday afternoon.

High pressure will begin to nose its way into the region by late
Friday, allowing a much cooler air mass to settle down over the
region by late Friday night. At this time feel there will be too
much cloud cover for the threat of frost Friday night into
Saturday morning, and gradient winds appear to be a bit to high as
well. Consequently will leave any mention of frost out of the
short term for now.

Long term...(saturday through thursday)
issued at 352 PM EDT Thursday Oct 20 2016

Chilly, unseasonable air will be in place in the wake of an upper
trough passage on Saturday, with afternoon highs in the middle and
upper 50s. An upper ridge will then begin building into the Central
Plains Sunday before slowly making its way into the Ohio Valley by
mid-week. This will keep eastern Kentucky in northwest flow through
Tuesday, while remaining on the back edge of a broad upper trough.
The upper level flow pattern is then expected to moderate and become
more zonal through the remainder of the period.

At the surface, Saturday will serve as the coolest day we have had
since may, with afternoon highs mainly in the mid 50s. Skies are
expected to clear through the day on Saturday, setting the stage for
a chilly night. Valley temps are expected to drop into the 30s by
Sunday morning. Heights will rebound on Sunday as a surface ridge
builds into the lower Mississippi Valley. A weak cold front looks to
move through early on Monday, with little consequence other than a
slight increase in clouds and a wind shift. Dry weather will hold on
through Wednesday, before another cold front takes aim at the area
Thursday. Seasonable temperatures are anticipated with lows
generally in the 40s (mid and upper 30s in the valleys at times) and
highs in the upper 60s/lower 70s.


Aviation...(for the 00z tafs through 00z Friday evening)
issued at 735 PM EDT Thursday Oct 20 2016

A strong cold front continues to approach our area from the west.
Thunderstorms will be possible at any of our terminals until
frontal passage occurs, although the chances for thunder are
steadily decreasing now that the sun is down. In general expect
cigs to drop into IFR/LIFR levels behind the front. Vsbys will
generally drop into MVFR categories with showers, possibly into
IFR with Post frontal showers and pre-frontal thunderstorms.
Winds will veer from the southwest at 5 to 10 kts to the northwest
behind the front at around 10 kts. Gusty winds to around 25 kts
will be possible in the vicinity of any thunderstorms and briefly
with and just behind the cold front.


Jkl watches/warnings/advisories...


short term...ray
long term...jvm

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