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Area forecast discussion
National Weather Service Jackson Kentucky
405 am EDT Mon Aug 19 2019

Short term...(today through tuesday)
issued at 405 am EDT Monday Aug 19 2019

The latest surface map features high pressure situated across the
southeastern conus, with a quasi-stationary frontal boundary
draped from the Great Lakes to the Midwest and into the Central
Plains. Aloft, a strengthening upper level ridge is centered
across southwest Texas. A short wave trough is moving east across
the Ohio and Tennessee valleys, with more zonal flow setting up
behind this feature. Plenty of high and some mid-level clouds have
overspread eastern Kentucky overnight, thwarting the diurnal drop
off compared to previous nights. Temperatures currently range
from the mid to upper 60s in the cooler locations out east, to the
lower to mid 70s elsewhere.

Hot weather will continue to be the main story through the
immediate short term, as the upper level ridge builds further
north towards the Texas Panhandle today. This will allow for upper
level ridging and higher geopotential heights to nose in across
eastern Kentucky. Highs will average in the lower 90s. Forecast
850 mb temperatures have come in a bit cooler today, so did not go
quite as high as it got yesterday, but still above MOS guidance.
Moisture looks to be a bit higher as well, which should also help
keep temperatures down a little. Besides a stray shower or storm
near the Bluegrass region, the upper level ridging should keep a
lid on convection this afternoon.

Mostly clear skies will be seen tonight, with lows ranging from
the mid to upper 60s in the valleys, to the lower 70s on the
ridgetops. On Tuesday, the ridge will buckle a bit, as short wave
energy traverses the Great Lakes/Ohio Valley region during the
afternoon. This will allow for a weaker cap, and have gone with
slight chance pops for most locations. Did go a bit higher near
the southeast terrain, as well as near the Bluegrass region, where
slightly better forcing could be in play. Highs will average in
the lower 90s, but generally a bit cooler than today, given the
additional cloud cover and slightly better storm chances.

Long term...(tuesday night through sunday)
issued at 343 am EDT Monday Aug 19 2019

The start of the extended period will become more active overtime,
as a cold front approaches and moves across the Ohio Valley. The
question for the period will be the progression of the front and
subsequently the amount of pops that come along with that. The
models suggest the better chances of seeing storms is now
Thursday, as frontal movement south is slower overall. There will
also be a bit better connection to the right entrance region of a
upper level jet progressing into the northeast. The models are
struggling with consistency from run to run on how far south the
frontal boundary makes it, and the European model (ecmwf) has been slower before
the latest 00z run opted to take it further into the Tennessee
Valley. Given the uncertainty couldnt see being too aggressive
in bringing drier air in area wide to end the week and also
typically these fronts struggle to make it south given the time of
year. However, did keep a good portion of the Bluegrass dry for
Saturday as a result of the latest guidance. By Sunday this
feature may actually shift back as an inverted surface trough, and
lead to some pops in the southeast portions of Kentucky at least.
It will be another warm day on Wednesday, but shouldnt be as
warm temperature wise given the increasing moisture. However, the
increasing moisture will make it steamy, but this will also depend
on cloud coverage. The remainder of the period will come in closer
to normal or perhaps just below for this time of year, with more
clouds and potential for storms.


Aviation...(for the 06z tafs through 06z Monday night)
issued at 234 am EDT Monday Aug 19 2019

VFR conditions will prevail through Monday night. Some patchy
River Valley fog will likely bring MVFR or worse conditions east
of I-75 through 13z; however no taf sites will be affected by
this, due to an increase in cloud cover and lower crossover
temperatures achieved Sunday afternoon. During the day on Monday,
some diurnally driven cumulus at 4-6k feet agl is expected, before
diminishing by dusk once again. South to southwest winds will
average around 5 kts or less through the period.


Jkl watches/warnings/advisories...

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