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000
FXUS61 KILN 272010
AFDILN

Area Forecast Discussion
National Weather Service Wilmington OH
410 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.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
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.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
Closed upper low will be working gradually northward to SE 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 /20Z TUESDAY THROUGH SUNDAY/...
Mostly clear skies will continue through the afternoon across the
area, with just a few VFR Cu for northern sites.

A large and pronounced stacked low pressure system will continue
to drift south from the Great Lakes area into the Ohio Valley
through the TAF period. For this afternoon, a tightening of the
pressure gradient will combine with efficient mixing to allow
winds to gust to 25-30kts for northern sites of KDAY, KCMH, and
KLCK, with gusts to 20-25kts possible elsewhere. These
west/southwesterly gusts will be diurnally-driven, with a fast
drop off expected towards 23z as temperatures begin to cool with
the approach of sunset.

Between 00z-12z Wednesday, moisture will gradually be on the
increase as the low moves south from the Great Lakes. Past 12z,
dynamic lift will increase in association with upper- level energy
rotating around the low pressure system. As such, expect showers
will develop and move west to east from mid- morning through early
afternoon. Expect a quasi- linear cluster of showers to move east
through terminal sites toward 18z, with best chance of showers for
eastern sites of KCMH and KLCK. Additional (re)development is
possible during the afternoon and early evening hours behind
(farther west of) initial activity.

While VFR conditions are anticipated through the majority of the TAF
period, some brief MVFR CIGs/VSBYs are possible in heaviest shower
activity Wednesday. Slight model differences on location and
timing of activity precludes anything other than a VCSH at this
time.

While instby will be on the increase after 18z, expect potential
isolated TS development to be fairly limited.

OUTLOOK...Local MVFR ceilings and visibilities possible with
showers on Wednesday. An isolated thunderstorm is also possible. Widespread
MVFR ceilings with local MVFR visibilities possible with showers
Thursday through Saturday.

&&

.ILN WATCHES/WARNINGS/ADVISORIES...
OH...None.
KY...None.
IN...None.

&&

$$
SYNOPSIS...Novak
NEAR TERM...Novak
SHORT TERM...Novak
LONG TERM...Coniglio
AVIATION...KC