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000
FXUS61 KILN 151050
AFDILN

Area Forecast Discussion
National Weather Service Wilmington OH
650 AM EDT Sun Apr 15 2018

.SYNOPSIS...
A potent low pressure system will bring widespread showers
today. Colder temperatures and drier air will follow the low
for Monday and Tuesday. Warmer temperatures and a chance of
showers are expected Wednesday when low pressure is forecast to
travel to the Great Lakes.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
1004 mb surface low pressure over Indiana this morning will
move to Ohio today. The low will deepen by a few millibars in
response to increasing short wave energy rotating around a
closed 500 mb low trailing the surface low.

A plume of deep moisture containing 1.5 inches PWAT is being
advected on the warm conveyor belt ahead of the low into a band
of frontal convergence, producing widespread moderate showers.
Those showers will continue into this afternoon until much
shallower moisture circulates in behind the low, producing a
diminishing trend from southwest to northeast. This event will
result in one to two inches of rainfall across the forecast
area. No flooding has been reported yet, but localized high
water may become an issue, and some river points along the
Whitewater, Great Miami and Scioto Rivers are being monitored
closely and may eventually go into minor flood.

Temperatures will be steady or slow falling as cooler air works
in behind the low. Expect afternoon readings to range from the
lower 50s west up to around 60 east.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
Surface low pressure will be over Northeast Ohio this evening,
before lifting to the Eastern Great Lakes tonight and then to
New England on Monday. Deep moisture will have exited, while
showers of rain and snow may linger in shallow moisture present
in the chilly and damp westerly flow behind the system. Showers
will also be also be aided on Monday by the cold pool aloft
associated with the closed upper low that will be traversing
Ohio. Little to no snow accumulation is expected due to warm
ground temps and marginal thermal conditions for snow crystal
development. However, high temperatures on Monday in the upper
30s will be more than 20 degrees below normal.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
Upper level low pressure to lift northeast from the Great Lakes into
southeast Canada Tuesday. Model trends slower with lingering snow
showers Monday night into early Tuesday. So will hang onto pcpn a
little longer. Freezing temperatures will be possible across some of
the area Monday night but clouds may hold temperatures up. Expect
lows Monday night to generally be in the upper 20s to lower 30s.

Surface high pressure to build across the area Tuesday, offering dry
weather. Temperatures look to be close to 10 degrees below normal
with highs from the upper 40s northeast to near 60 southwest.

Surface and upper low to track through the Great Lakes Wed/Wed
night. Warm front to lift north across the region with surface wave
passing to our north. Moisture is limited with this system so will
limit pops to chance category with the best chance across the north.
In the warm sector temperatures will be a little above normal with
Wednesdays highs from near 60 north to near 70 south.

Model timing differences exist regarding how quick precipitation
chances end. ECMWF further south and slower ending the pcpn with the
GFS being quicker. Will used a blended approach hanging onto a
chance across the northeast into Thursday afternoon. Temperatures
look to be around 10 degrees blow normal with highs Thursday from 50
north to the upper 50s south.

Surface high pressure to build across the area offering a return to
dry weather for the end of the week. Temperatures to moderate some
but still remain below normal with highs Friday from the lower 50s
north to the upper 50s south.

Large timing and placement differences exist regarding the approach
of the next low and associated precipitation next weekend. Due to
model solution differences confidence decreases. Will slow onset of
precip, allowing a slight chance of a shower to develop Saturday
evening. Temperatures to moderate a little closer to normal with
highs from the upper 50s north to the lower 60s south.

&&

.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
-- Changed Discussion --
Large swath of moisture and lift ahead of low pressure and a
cold front continues to trigger showers and lowered ceilings
and visibilities at TAF sites. Ceilings as low as LIFR have
developed at DAY and ILN with showers, and with another surge
of showers evident on upstream radar, similar conditions will
persist through the morning and most of the afternoon. We will
then see drier air beginning to work in behind the system that
will probably allow VFR for awhile later this afternoon. A
return to MVFR is forecast late in the period in lingering low
level moisture behind the low.

Wind direction will vary with respect to location of the low as
it lifts through Ohio. CVG and LUK will see a shift from south
to west. Northern sites ILN DAY CMH and LCK will see direction
change from east to southeast with gusts to 20 knots before the
shift to west occurs.

OUTLOOK...MVFR conditions and gusty winds likely Monday.
-- End Changed Discussion --

&&

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

&&

$$
SYNOPSIS...Coniglio
NEAR TERM...Coniglio
SHORT TERM...Coniglio
LONG TERM...AR
AVIATION...Coniglio