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Area forecast discussion 
National Weather Service Jackson Kentucky
630 PM EDT sun Jul 24 2016

issued at 630 PM EDT sun Jul 24 2016

WSR-88D radar is showing isolated to scattered showers and storms
popping up across the region. Minor update to pops otherwise
forecast is on track.


Short term...(this evening through Monday night)
issued at 343 PM EDT sun Jul 24 2016

Models are in decent agreement through the short term. Mid/upper
level flattened ridge over the region buckles through the period
in response to a short wave trough digging through the mid-west.
A surface cold frontal boundary will be nudged southeastward
reaching as far as the Ohio River by late Monday night. The
threat of rain will increase through the short term as this system
approaches our area. Current model runs suggest that should any
organized convection associated with the approaching system
develop, it would not reach into eastern Kentucky until Monday
night. That being the case, unfavorable timing may inhibit any
widespread significant rainfall until beyond the short term

Thicknesses Monday are not quite as high as today, and h850 temps
appear slightly cooler on average. So afternoon highs may be just
a tad cooler Monday afternoon. In addition, surface boundary does
not make it to the Ohio River until late Monday night.
Consequently the more significant moisture pool ahead of the sfc
boundary does not make it into our area Monday afternoon...
remaining further north in central Ohio/Indiana. Therefore our
heat index values will continue to rise to around 100 degrees
Monday afternoon, a little shy to warrant any type of heat
advisory headlines.

With respect to Hydro issues, storm motions remains well below 10
kts through the period. Forecast soundings also suggest a gradual
increase in pwats. So any thunderstorm activity Monday and Monday
night may be a bit more efficient at producing heavy rain as
compared to the last couple of days. Consequently locally heavy
rain may become an increasing threat with time. Will continue to
mention this potential in the severe weather potential statement.

Long term...(tuesday through sunday)
issued at 343 PM EDT sun Jul 24 2016

The dominant southern Continental U.S. Ridge is forecast to separate into
two centers during the period, one over The Four Corners region
and the other over the western Atlantic. The weakness in between
will be right over the Ohio and Tennessee valleys. At the surface,
a frontal boundary will be located along the Ohio River Tuesday
morning. The models are fairly consistent in keeping this front
pretty much in place, with minor wiggles north and south, through
the rest of the work week. The front is progged to be shoved
through only to be followed by another front dropping into the
Ohio Valley over the weekend.

All of this points to a fairly unsettled period with persistent
chances for showers and storms. Pwats remain near 2 inches through
the period so the main concern with these repeating showers/storms
will be for flooding, even though it has been fairly dry of late.
Temperatures are expected to cool slightly, with daytime highs
remaining in the 80s for most locations. However, dewpoints will
remain pretty consistent in the low 70s, so it will continue to be
very muggy with no real relief in sight there.


Aviation...(for the 18z tafs through 18z Monday afternoon)
issued at 233 PM EDT sun Jul 24 2016

Other than some spotty pre-dawn MVFR fog at a few terminals went
with a predominant VFR forecast. Guidance was too pessimistic with
visibilities and therefore chose to lean closer to persistence. Cumulus field
will linger into the early evening. Will see typical summertime
garden variety pop up showers and thunderstorms across the area
this afternoon as well. However, coverage will not be widespread.
Therefore no plans to mention any thunder at any particular site
until it become evident that a terminal might be affected. Winds
will remain light this afternoon, generally southwesterly around 5
kts or less. Winds will pick up just a bit Monday as a cold front
settles down into the Ohio Valley.


Jkl watches/warnings/advisories...

short term...ray
long term...Abe

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