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Area forecast discussion 
National Weather Service Jackson Kentucky
423 am EDT sun Jul 31 2016

Short term...(today through monday)
issued at 415 am EDT sun Jul 31 2016

Early this morning, the region was under the influence of a
trough extending from the Great Lakes region south into the mid MS
valley region. A ridge was in place from the Desert Southwest and
then north into the High Plains. Meanwhile another ridge centered
east of Bermuda extended into the northern Gulf of Mexico and the
Gulf Coast states. Locally, some light showers and a times a stray
thunderstorm or two are moving across the area from time to time
in the moist environment as weak shortwaves pass. Some fog and
low clouds has also developed in some locations regional ASOS and
AWOS sites, with the visibilities most reduced south of line from
Monticello to London to Jackson to Paintsville. Cpf, pbx, i35,
1a6, and byl are all reporting either low clouds or fog with vis
below one half of a mile. At the surface, a nearly stationary
boundary separates high pressure with drier air centered over the
Great Lakes and high pressure centered over the southeast and an
associated much more moist airmass.

For the remainder of the night, some stray to isolated showers
and perhaps a thunderstorm or two will move east northeast across
the area. Some of the convective allowing models have an increase
in coverage of this over the next couple of hours as has happened
during a few of the past mornings. Fog and low clouds will also
linger, but should begin to lift by around sunrise and then
dissipate a couple of hours or so later. The model consensus is
for any convection lingering past sunrise to dissipate by around
10 am or so. However, daytime heating should lead to cumulus
building by midday into the afternoon hours. The deepest moisture
should be across the southern half to two thirds of the area with
the best moisture nearer to the Virginia and Tennessee borders where chances
of showers and thunderstorms appear best during the afternoon and
evening. A weak shortwave moving through the Ohio Valley may also
aid in convective development as perhaps any lingering outflows or
differential heating boundaries from recent rains. Also, as a
more significant shortwave moves through the Great Lakes region,
the boundary should begin to sag into the commonwealth. Highs
should reach near normal levels for the end of July.

The boundary should sag into eastern Kentucky tonight and then become
nearly stationary through Monday roughly halfway through the
eastern Kentucky in the vicinity of the mountain Parkway. This should
lead to precipitable water dropping from the nearer to 1.5 inches across the
southern half to two thirds of the area today to closer to 1.25
inches tonight. The deeper moisture and higher precipitable water though is
progged to linger near the Tennessee and Virginia borders tonight and into the
day on Monday. More in the way of a lull in convection is
anticipated tonight compared to recent nights, with the possible
exception of the more southern locations. Convection should peak
diurnally on Monday with the chances best south of the boundary in
the more southern locations from the Lake Cumberland region and
the Cumberland Valley east of the Virginia border.

Long term...(monday night through saturday)
issued at 332 am EDT sun Jul 31 2016

Warm and muggy weather will continue through the extended period,
with daily highs in the mid to upper 80s, and at times 90, on tap,
along with overnight lows in the mid to upper 60s with a few 70
degree readings possible. Rain chances were a bit tricky to pin down
due to the amount of uncertainty in the models this time around. In
general, we can expect dry conditions from late Monday night through
late Tuesday afternoon. Periods of scattered showers and storms are
expected across the area from Tuesday evening on through to the
weekend, with peak coverage during the afternoon and evening hours
each day. The showers and storms will be sparked by a series of
upper level disturbances and their associated surface frontal
boundaries. These fronts will likely be weak and not well defined,
hence the fairly low rain chances in the forecast.


Aviation...(for the 06z tafs through 06z Sunday night)
issued at 220 am EDT sun Jul 31 2016

Isolated convection continues to move across southern portions of
the County Warning Area and this may be in the vicinity of sme, loz, and jkl over
the next few hours. The other concern is low stratus and fog
development which is highly dependent on low and mid clouds and
where rain has fallen over about the past 12 hours. For now, we
have kept sites mainly in the MVFR range for vis restrictions
from around 9z to about 13z due to uncertainty, but in line with
guidance. Guidance had a period of IFR at sme and generally
followed this. Outside of any convection, winds will remain light
and variable. Convection on Sunday will be highly variable, as
well, with loz and sme having the highest chances, but also
possible at jkl and sjs. Accordingly, have included a thunderstorms in the vicinity for a
time after 16z for those sites.


Jkl watches/warnings/advisories...


long term...Arkansas

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