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fxus63 kpah 162341 
afdpah

Area forecast discussion
National Weather Service Paducah Kentucky
640 PM CDT Mon Oct 16 2017

Update...
issued at 640 PM CDT Mon Oct 16 2017

Updated aviation discussion for 00z tafs.

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Short term...(tonight through Wednesday night)
issued at 307 PM CDT Mon Oct 16 2017

Under northwesterly flow aloft, a surface ridge axis will settle
over the pah forecast area this evening and overnight, yielding
virtually clear skies and generally light winds, though northerly
winds may gust above 10 knots mainly in western Kentucky for a few
hours this afternoon. After sunset, winds are expected to go calm
or near calm, and under clear skies, patchy frost will be a
possibility where lows are forecast to be in the upper 30s. This
will be most likely across southern IL, northern parts of
southeastern MO, and most of southwestern in.

Tue through Wed night, the high pressure ridge will drift off to
the east allowing surface winds to gradually gain a southerly
component. Below average temps are forecast to tick up a few
degrees each day to about average through the short term. The
pressure gradient is progged to increase a bit late Wed in
response to a dry cold front passing by to the north, resulting in
a gentle southerly breeze Wed night. Dry conditions will continue,
with only a modest increase in dewpoints by midweek.

Long term...(thursday through monday)
issued at 307 PM CDT Mon Oct 16 2017

Confidence remains high into the weekend then decreases Sunday into
Monday as a front makes it way through the region.

Models have been in good agreement at least through Saturday. They
place a surface high just to our east and allow a moist southerly
flow over the region. This will keep temperatures well above
normal anywhere from 5 to 10 degrees above normal. It will also
supply ample moisture ahead of an approaching cold front late in
the weekend. Models have been in conflict with this system's
timing or even its existence a couple days back. However they have
come into much better agreement on a cold front passage Sunday.
In fact the blend produced likely pops Sunday. I dont know if I
can keep the likely pops going but will wait and see what
collaboration yields. Also models are advertising some weak
indications of possible thunder with Li's a negative one to two
and some elevated weak cape of less than 500 j/kg2. Also the k
index is running in the low 30s. This may result in the
introduction of thunder but will wait at least another cycle
before doing so at least. Pw's are also coming in a little high at
1.72 so may consider bumping to moderate rain if this starts to
trend run to run.

&&

Aviation...
issued at 640 PM CDT Mon Oct 16 2017

VFR conditions and a nearly cloud-free sky will prevail through the
valid forecast period as a ridge of high pressure shifts east across
the area tonight and to our east on Tuesday. As this occurs, calm
winds tonight will pick up from the south/southeast around 5 knots
on Tuesday. While fog is not explicitly in the forecast tonight,
some patchy evaporation/steam fog in river valleys is not completely
out of the realm of possibility.

&&

Pah watches/warnings/advisories...
Illinois...none.
MO...none.
In...none.
Kentucky...none.
&&

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