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886
FXUS61 KILN 211749
AFDILN

Area Forecast Discussion
National Weather Service Wilmington OH
149 PM EDT Sat Apr 21 2018

.SYNOPSIS...
High pressure will push slowly east across the Great Lakes
region through Sunday. This will provide for dry conditions and
slightly below normal temperatures through the weekend. An
upper level low pressure system moving out of the Mississippi
Valley will bring a chance of showers for the start of the work
week.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Updated the forecast to allow the freeze warning and frost
advisory to expire. Brought in a little extra cloud cover to the
north this morning, based on the latest satellite loop.

Rest of forecast is looking ok right now.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
The mid level ridging will continue to weaken tonight into
Sunday with weak pieces of mid level energy pushing east across
the region overnight. This will help keep a fair amount of
mainly high level cloudiness in place across our area. An upper
level low will begin to slowly lift out of the lower
Mississippi Valley through the day on Sunday, but with still
some weak mid level riding hanging on across our area, dry
conditions will prevail through the day. Lows tonight will be in
the upper 30s to lower 40s with highs on Sunday in the low to
mid 60s.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
Sunday night an upper level low will be located near Arkansas and be
mostly cut off from the main flow. The vertically stacked low will
slowly push northeast with light rain moving into the area Monday
evening. GFS forecast soundings are not to impressive, with mainly
light rain and cool weather expected. The low will then remain quasi-
stationary over the area Tuesday as an upper level disturbance over
Canada remains to far north to pick the low up.

By Wednesday the upper level disturbance over Canada will push far
enough south to help pull the low northeast and out of the area. The
latest run of the 00z models this morning are in general agreement
with a slightly further north track of the low compared to the 12z
model runs (except the CMC), so have nudged the chance of
precipitation further north.

Wednesday night into Thursday models begin to quickly diverge as
each handles the ejection of the aforementioned low differently.
Both the GFS and ECMWF dive a secondary upper level shortwave
southeast out of Canada, but the GFS is much stronger with the
shortwave and even wrap it up into a closed low. The ECMWF keeps the
wave open. For now have split the difference between the models
given the wide range of uncertainty. By the end of the extended a
more potent upper level disturbance will dive south pushing a cold
front through the region. Both the ECMWF and GFS have the front
pushing through the area Friday or Saturday.

&&

.AVIATION /17Z SATURDAY THROUGH WEDNESDAY/...
H5 ridge will remain across the region, but will become
elongated over the next 24 hours as an upper low slowly works
east through the srn plains.

Mid clouds will affect the nrn tafs during first part of the
period, with high clouds affecting the rest of the tafs. The mid
clouds will move east of the nrn tafs by 00-03Z, leaving only
cirrus for the rest of night.

The nrn edge of the cirrus band drops south after 12Z Sunday,
allowing the nrn tafs to go scattered.


OUTLOOK...MVFR ceilings will be possible Monday night through
Wednesday.

&&

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

&&

$$
SYNOPSIS...JGL
NEAR TERM...Sites
SHORT TERM...JGL
LONG TERM...Haines
AVIATION...Sites