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Area forecast discussion...updated 
National Weather Service Jackson Kentucky
400 am EDT Tuesday Jul 7 2015

Short term...(today through wednesday)
issued at 355 am EDT Tuesday Jul 7 2015

Fairly quiet morning on tap for the commonwealth with clear skies
and some patchy fog...but not nearly as foggy as it was the previous
night. Throughout the day today...expect cloud cover to increase as
a frontal boundary makes its way toward eastern Kentucky. Ahead of
this front moisture will increase to near 2.0 inches...making things
feel very sticky. By afternoon...showers and thunderstorms will
spread across the region...with highest chances in the northwest portion of
the forecast area. This is also where the best instability resides
(within Storm Prediction Center/S marginal risk area) with little to no shear. That
being said...some of the storms could produce gusty winds...but the
bigger concern is the heavy rainfall. Much of the forecast area has
received anywhere from 5 to over 10 inches of rain this past week so
will have to keep an eye on any slow moving or training storms. The
majority of storms should wane by late evening...with the loss of
daytime heating. However the chances for showers and storms continue
on weak shortwaves embedded in the upper level flow
provide additional chances for convection.

Temperatures will hover in the middle 80s which is right around normal
for the beginning of July. Overnight lows will be on the mild side
as well...near 70 degrees. The bigger story here are the dew points
which are expected to stay near 70 degrees throughout the short term
period...allowing for uncomfortably muggy conditions.

Long term...(wednesday night through monday)
issued at 400 am EDT Tuesday Jul 7 2015

The models are in general agreement with a slow building ridge
over the southeast and deep south through the first two thirds of
the period before it slips westward in response to a building
trough over the northeast. Initially...during this evolution...
several shortwaves will run southwest to northeast just north of
the jkl County Warning Area Wednesday into Thursday. This path gets shunted north
as the ridge builds to our south so that by Friday and Saturday
the energy will be passing well to the north...through the Great
Lakes. However...the track will pivot more southeast...for these Sunday with several prognosticated to graze east Kentucky
through the day Monday. Given the decent agreement among the
models a general blend was favored along with a healthy embedded
diurnal cycle with probability of precipitation peaking late each afternoon.

Sensible weather for the extended will see the warmth build for
the area in addition to the ongoing humid conditions. Some of the
best chances for showers and storms will start the extended as a
wavy front slowly lifts north through east Kentucky when a surface
wave moves through. The next surface wave looks to pass just north of
the area on Thursday with its best precipitation chances kept in Ohio. In
the wake of this...though...the front will likely sag back south
where its ability to trigger convection will compete with building
heights aloft. For Friday...the boundary lifts back north in the
models but may get hung up just northeast of Kentucky. This will
probably contribute to the ring of fire effect...around the middle
level ridge to the south...allowing for convection to remain a
concern for our northeast parts of the County Warning Area Saturday afternoon
while by Sunday afternoon the front could be sinking back
southwest with additional showers and storms a threat. The European model (ecmwf)
then has this boundary settling over the area on Monday with
additional diurnally enhanced convection anticipated. While
localized heavy rains cannot be ruled out...the pattern looks
more favorable for a break in the excessive rain events of the
past several days...though at the price of steamier conditions
with middle and upper 80s for highs in most places.

The CR grid blend came in reasonably well with the bulk of any
adjustments made to the probability of precipitation and sky to account for a good diurnal
cycle with these grids. As for temperatures...did tweak the lows
a bit each night to represent some minor terrain effects.


Aviation...(for the 06z tafs through 06z Tuesday night)
issued at 155 am EDT Tuesday Jul 7 2015

Generally MVFR conditions prevail across taf sites
currently...with a drop to near IFR or below at sme and loz by 09z
likely. The remaining sites should stay at MVFR for the remainder
of the night before improving to VFR by 13z. The first showers and
storms of the day will likely begin moving across the area around
18z so have included thunderstorms in the vicinity at sym where there are higher chances
for probability of precipitation...with vcsh elsewhere. Assuming the taf sites see some
rain tomorrow...have introduced br near the end of the taf period
across all taf sites. Winds will be light and variable through
most of the period with higher gusts associated with any


Jkl watches/warnings/advisories...


Short term...jvm
long term...greif

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