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000
FXUS61 KCLE 221055
AFDCLE

Area Forecast Discussion
National Weather Service Cleveland OH
655 AM EDT Sun Jul 22 2018

.SYNOPSIS...
Low pressure over southwest Ohio will continue slowly drifting
south today, reaching the Tennessee Valley by Monday before
dissipating over Georgia on Tuesday. A weak trough of low
pressure will linger over the area on Tuesday. A cold front will
approach the Great Lakes region on Wednesday and cross the
forecast area by Thursday. High pressure will build in from the
west by the end of the week.

&&

.NEAR TERM /THROUGH MONDAY/...
Few changes with the forecast updates this morning. A nice
pocket of clearing bisects the forecast area this morning and
while I wouldn`t say that we`ll be seeing the sun today, several
areas will see blue skies for a bit this morning. Have tweaked
sky coverage grids a bit to reflect current conditions.
Otherwise, rain will rotate around and north of the area this
morning. Most areas will stay dry for a good chunk of the day
before rain fills in again this evening.

Previous Discussion...
A vertically stacked low continues to pester the region as it
slowly drifts southward out of the Ohio Valley. Meanwhile,
another low pressure system moving northwest across upstate New
York is pulling a large area of stratiform rain across the
Appalachians and into the eastern Great Lakes region. With two
low pressure systems straddling the area, the weather will
remain generally unsettled for today and into Monday.

This morning, shower activity has been limited to the
stratiform rain moving northwest over portions of NW PA and far
NE Ohio. Have categorical pops this morning, diminishing to
likely pops as the eastern low moves towards Canada. Dry air has
wrapped in between the two low pressure systems so will be
interesting to see how much rain can develop today outside of
this stratiform rain region. It appears that new convection
will develop southeast of the forecast area with daytime heating
and advect north later today into tonight as the two surface
lows separate from each other, but coverage doesn`t look
fantastic so slight chance to low chance pops are appropriate
right now at this time. For Monday, low pressure continues
drifting well south of the area but residual troughiness over
the area will allow for convection to develop, especially during
the afternoon hours with the diurnal cycle. Highest chances will
be in the southeast portions of the area with the highest
instability and southeasterly flow. Temperatures today will be
cooler than normal with widespread cloud cover and rain in and
around the area. Temperatures will rebound a bit on Monday with
some southeasterly flow returning to the area and perhaps some
breaks in the clouds between low pressure systems.

&&

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
The stacked low will continue to fill in early this week as it
meanders southward. The upper level trough will extend as far south
as the Gulf States and may become cut off briefly. The surface low
will weaken during this time, yet remain nearly stationary as high
pressure off the eastern seaboard strengthens. This will continue
the weak mid level flow from the eastern seaboard into the middle of
the week. The continued source of moisture combined with modest
instability will keep the weather unsettled. A weak perturbation
ejecting out from southern Canada Tuesday evening will provide
enough energy for an increase in showers and thunderstorms coverage.
Best chances for thunderstorms will correspond with diurnal heating.
Despite increased cloud coverage, temperatures will be near
seasonable normals. The east coast high will slide east Wednesday
night allowing cutting off the moisture support and pulling some
drier air into the mid levels.

&&

.LONG TERM /THURSDAY THROUGH SATURDAY/...
Attention will turn to a well defined wave moving across southern
Canada on Thursday.  This feature and its associated cold front will
move across the area during the day. The source of lift will trigger
storms, however the lack of moisture advection will keep coverage
scattered. The front will be followed by surface high pressure and a
drying period Friday. A stalled frontal boundary will set up across
Ohio on Saturday, though best moisture will be south.

&&

.AVIATION /06Z Sunday THROUGH Thursday/...
A pesky low pressure remains in place over the Ohio Valley,
allowing for a mix bag of ceilings and a large area of rain
mostly east of the forecast area. A large pocket of clearing has
developed over the central part of the forecast area, scattering
out ceilings at a couple terminals this morning. Meanwhile, it
has rained most of the morning at KERI with several more hours
of rain possible. Clouds will fill in throughout the day with
non-VFR ceilings possible in and around any rain in the area.
The large area of rain at KERI and east will rotate around and
north of the area and will likely avoid most of the terminals
until later this afternoon. With the loss of daytime heating,
ceilings will likely lower across the board to MVFR or lower for
tonight into Monday. Winds will be easterly to northeasterly
to start, perhaps becoming a bit more southeasterly as a low
departs to the north.

OUTLOOK...Periods of non-VFR possible Monday through Wednesday.

&&

.MARINE...
Vertically stacked, cut-off low pressure continues to slowly
pinwheel across the Ohio Valley through the forecast period. A
coastal low that moved inland from Delmarva will wash out over
western NY today. This will allow for weaker winds than anticipated
across the eastern basin of Lake Erie. As a result, will drop the
SCA for this area. Otherwise, the northeast winds will strengthen
today, strongest in the western basin as high pressure moves into
Michigan. The winds and fetch will produce small craft conditions
over the central and western basins as well as a high risk of rip
currents. Winds will relax tonight as the low weakens. Winds will
shift and increase as a few troughs move by to the north over the
next few days, but not looking at speeds above 15 knots at this
time. Weather will be unsettled with on/off showers and
thunderstorms.

&&

.CLE WATCHES/WARNINGS/ADVISORIES...
OH...Beach Hazards Statement from 10 AM EDT this morning through
     this evening for OHZ003-007-009>012.
PA...None.
MARINE...Small Craft Advisory from 10 AM this morning to 10 PM EDT this
     evening for LEZ142>147.

&&

$$
SYNOPSIS...Sefcovic
NEAR TERM...Sefcovic
SHORT TERM...Jamison
LONG TERM...Jamison
AVIATION...Sefcovic
MARINE...Jamison