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Area forecast discussion 
National Weather Service Wilmington Ohio
1045 PM EDT Tue Sep 27 2016

Synopsis...
an upper level low will work into the region on Wednesday and
influence the weather pattern through the remainder of the week.
This feature will allow for cool and cloudy conditions with
scattered shower activity.

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Near term /until 6 am Wednesday morning/...
upper level low centered over northern Michigan to drop slowly
south into the Ohio Valley. Skies which have been mostly clear
through the evening will see an increase in clouds overnight.
Any precipitation will hold off until close to sunrise. Have made
only a minor change, slowing up precipitation with light showers
developing into the northwest toward sunrise. With few clouds and
dry air in place, temperatures will continue to drop off and then
level out late with increase in clouds. Have lows in the upper 40s
to lower 50s.

Previous discussion...
clear to mostly clear skies will give way to an increase in clouds
overnight as an upper level low approaches the area. Precipitation will
hold off most of the night, however some light shower activity
will move into northwestern portions of the forecast area by
morning. Although initially there will be dry air in place, expect
an increase in moisture and lift late in the overnight hours.

Expect a quick drop off in temperatures for the first half of the
night with less cloud cover and drier air. Went on the cooler side
of guidance for low temperatures overnight.

&&

Short term /6 am Wednesday morning through Thursday night/...
increased precipitation chances for the day on Wednesday as the
upper level low pressure system approaches the area. Showers with
isolated embedded thunder is expected. An initial push will move
through during the morning and into the afternoon with additional
scattered shower activity behind this first push of precipitation.

Precipitation during this time will be somewhat diurnal with less
coverage at night and more during the day. Cloudy and cool
conditions will be quite prevalent through this time with high
temperatures in the 60s and lows in the middle 40s to middle 50s.

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Long term /Friday through Tuesday/...
closed upper low will be working gradually northward to southeast Indiana
on Friday. Showers will be likely in the moist and weakly unstable
circulation around the upper low and its cold pool aloft, aided by
low level convergence associated with an inverted surface trough. As
the upper low continues to exhibit slow movement on a path to the
central Great Lakes, a good chance of showers will persist through
Saturday.

When the low lifts farther to the northeast on Sunday, decreasing
moisture and forcing will be evident. There will be a slight chance
of showers in shallow residual moisture. Dry weather appears in the
forecast for Monday and Tuesday under high pressure at the surface
and aloft.

Expect below normal highs in the 60s Friday and Saturday under
clouds, precip, and low geopotential heights. A rebound back into
the 70s should be noted by Tuesday in a regime of warm advection
and insolation.

&&

Aviation /03z Wednesday through Sunday/...
large upper level low centered over the northern Great Lakes to
drift slowly south into the Ohio Valley Wednesday. Skies will be
mostly clear through the evening with mainly high level clouds
across the area. Moisture will increase overnight with showers
moving into western Ohio toward sunrise.

Lift and moisture will become more favorable as the upper low
settles into the Ohio Valley Wednesday afternoon. Have prevailing
showers developing late morning into the afternoon from west to
east. Have kept ceilings VFR through the period but some brief MVFR
cigs/vsbys are possible in heaviest shower activity Wednesday
afternoon. Instability increases Wednesday afternoon but remains
marginal. Therefore...have omitted mention of thunder to potential
limited coverage.

Outlook...MVFR ceilings with local MVFR visibilities possible
with showers Wednesday night through Saturday.

&&

Iln watches/warnings/advisories...
Ohio...none.
Kentucky...none.
In...none.

&&

$$
Synopsis...Novak
near term...Novak/AR
short term...Novak
long term...coniglio
aviation...Arkansas

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