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Area forecast discussion 
National Weather Service Paducah Kentucky
555 PM CST Sat Nov 22 2014

Update...
issued at 555 PM CST Sat Nov 22 2014

Updated aviation discussion only.

&&

Short term...(tonight through Monday night)
issued at 243 PM CST Sat Nov 22 2014

The lingering shower activity will continue over the southeast
Missouri foothills to the I-64 corridor in southern Illinois through
the remainder of the afternoon and into the early evening hours.

The upper low over southwest Texas at 200 PM today will become
more negatively tilted and sharpen over eastern Texas/southeast
OK/western la/southwest Arkansas by 6 am CST (12z sunday). Given the
further south trajectory of this sharp, negatively tilted wave and
the phasing of the wave with the main trough axis, any instability
will be significantly lacking during the 12z-18z Sunday time frame
as the southern wave rotates around the base of the trough into
the weather forecast office pah forecast area.

However, enough instability/shear/moisture will be in place east
of the Land Between The Lakes, across the southern pennyrile
region of west Kentucky, to support some stronger updrafts. Still
cannot rule out an isolated strong storm or two during the late
morning into the mid-afternoon hours on Sunday in this area.

The transition from one time period to another is a Little Rocky
with respect to pop/weather. To provide a somewhat realistic
increase/decrease in the timing of weather from one time period to
another, had to make some sharp adjustments, especially for late
tonight through early Sunday morning.

The most dramatic change in temperatures will late Sunday night
into Monday morning as the front pushes through the area. The
precipitation shield associated with the upper forcing of the
trough should still stay above freezing so that any remaining
precipitation will be in the form of light rain before ending on
Monday.

Long term...(tuesday through saturday)
issued at 243 PM CST Sat Nov 22 2014

Surface high pressure will move east of our region Tuesday night and
Wednesday as a 500 mb trough pushes east across the forecast area Tuesday
night. While dry conditions will accompany this first 500mb trough,
the second will have some limited moisture to work with along with
some surface convergence along a cold front that will move across
the forecast area Wednesday night. As a result will maintain the consensus
small pops for Wednesday and Wednesday night, for what looks to be a
minimal quantitative precipitation forecast event. The event could end as a light wintry mix across
the east (sw in and adjacent areas of Illinois & ky) Wednesday evening.
Will maintain dry conditions in the northwest 500 mb flow for Thursday.

The well below temperatures will continue in the northwest 500mb flow
through the extended forecast period with Friday offering the
coldest temps. The upper flow flattens out to more of a west-northwest
orientation by Saturday with some slight moderation in temps
beginning.

&&

Aviation...
issued at 555 PM CST Sat Nov 22 2014

A major transition toward lower cigs and vsbys will occur toward the
end of the 00z taf period. As low pressure moves NE toward the
region thru Sunday morning, increasing moisture and instability will
lead to lowering cigs and vsbys. Cigs will remain VFR through most
of tonight before steadily dropping late tonight/early Sunday. MVFR
cigs and vsbys will trend toward IFR Sunday morning especially at
kcgi and kpah where widespread rain will arrive first. Some
scattered light showers may be around primarily in the nwrn and nrn
sections tonight. Srly winds will settle at or below 10 knots tonight before
some slight strengthening and backing toward the se Sunday.

&&

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

$$

Short term...Smith
long term...receiver station
aviation...db

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