Area Forecast Discussion
Issued by NWS Jackson, KY

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FXUS63 KJKL 200745

Area Forecast Discussion
National Weather Service Jackson KY
345 AM EDT WED JUL 20 2016

.SHORT TERM...(Today through Thursday)
Issued at 345 AM EDT WED JUL 20 2016

Drier air continues to filter into the region early this morning as
a frontal boundary washes out to our south. This will allow dew
points to lower into the mid and upper 60s, making things slightly
more comfortable. However, we won`t see much change in
daily temperatures as afternoon highs are expected in the upper
80s and lower 90s both days. Overnight lows will be slightly
cooler, in the mid and upper 60s, before returning to the 70s by
the end of the work week. The weather will remain dry as high
pressure stays in control of eastern Kentucky.

.LONG TERM...(Thursday night through Tuesday)
Issued at 345 AM EDT WED JUL 20 2016

The driver for the long term forecast will be the continual
building of a persistent upper level ridge into the Ohio Valley,
enabling the full effects of summer to be felt across the region.
This trend of hot, humid weather will continue throughout the
weekend as heat indices approach and at times supersede the 100
degree threshold Friday through Sunday. Although current model
soundings indicate ample instability throughout the weekend, a
strong cap in conjunction with lack of upper level support and
deep layer moisture will preclude thunderstorm development
Saturday. That being said, a brief reprieve from the heat may be
possible Sunday afternoon as moisture advects into the area ahead
of a shortwave dipping through the Great Lakes as the cap weakens
ever so slightly, allowing for the development of a diurnally
driven thunderstorm or two.

Towards the beginning of the next week, the persistent ridge will
slowly retreat to the southwest supporting a more zonal flow over
the northern half of the CONUS. As previously mentioned, a
shortwave confined to this zonal regime will develop and intensify
over the Great Lakes, supporting a surface low over Michigan
tracking along the US-Canada border. The associated cold front is
progged to move through the Ohio Valley during the afternoon hours
Monday evening, providing the region with its best chance of
showers and thunderstorms in the long term as it intrudes on
instabilities of around 1500 J/kg. Although a few strong to severe
thunderstorms cannot be ruled out, abysmal deep layer shear should
inhibit severe potential. Following this front, weak cold air
advection should provide for a cooling down across the region.


.AVIATION...(For the 06Z TAFS through 06Z Wednesday night)

Fog will be the primary concern tonight into the morning hours. The
drier airmass seeping in and exact extent of cirrus from
convection to the west complicate things. Visibilities have
trended upward in the models over the past few hours as well, so
hedged more towards an optimistic forecast while still allowing
for SME to drop to LIFR towards dawn. At the other sites, MVFR to
VFR VIS is expected. Ridging in place will keep north/northeast
winds light through the forecast period.


.JKL Watches/Warnings/Advisories...


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