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479
FXUS61 KCLE 140738
AFDCLE

Area Forecast Discussion
National Weather Service Cleveland OH
338 AM EDT Tue May 14 2024

.SYNOPSIS...
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A near stationary boundary will linger across northwest Ohio
today before shifting east as a cold front late this evening
into tonight and then stalling again across central Ohio for
Wednesday as a low pressure system moves east across the Ohio
River Valley. High pressure returns on Thursday before a warm
front lifts north on Friday followed by a cold front Friday
night into Saturday.
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&&

.NEAR TERM /THROUGH WEDNESDAY/...
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Currently, a quasi-stationary boundary associated with a low
pressure system near James Bay lingers to the northwest of the
area as another low pressure system over the central US
continues to develop. The associated upper level trough is
meandering east to eventually move across the Ohio River Valley
tonight, but with the continued slowing of this system in
models, have again delayed the chance of PoPs until late this
afternoon into the evening. Although moisture content will
continue to increase in the meantime, there is very little, if
any, mesoscale or synoptic forcing to allow for any widespread
development. Opted to keep chance PoPs this afternoon,
especially across the southern counties as marginal diurnal
instability may be enough to result in isolated showers. As the
overall system becomes more progressive late this afternoon into
the overnight hours, the low level and synoptic forcing becomes
better with an area of vorticity tracking east with weak
isentropic lifting. The best lift will be closer to the center
of the low (or across the southern counties of the CWA) which is
where there is highest confidence of showers tonight. Will have
to continue to monitor the progression of this system to see if
it slows anymore and possibly delays onset even later.

On Wednesday, the center of the low begins to shift closer to
the Mid-Atlantic Coast allowing for showers to gradually
diminish from west to east. Some hi-res models have suggested a
period on Wednesday afternoon with a notable increase in
instability across the eastern counties and suggest an
environment capable of a line of showers and thunderstorms to
move from near I71 east. Severe weather is not expected at this
time, but there remains quite a bit of uncertainty in this
forecast with how slow the system is moving.

Highs through the period will climb into the upper 60s to low
70s with overnight lows remaining mild and only dropping into
the mid to upper 50s.
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&&

.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY NIGHT/...
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A weakening cold front should be south of the region by late
Wednesday evening with showers and thunderstorms shifting southward
with the boundary. A ridge of high pressure then pushes southward
into the region from Ontario as an upper level ridge also briefly
builds overhead. This upper level ridge should limit the coverage of
any convection on Thursday. However there may be just enough
convergence along a lake boundary to warrant a low chance mention of
showers or thunderstorms. As a warm front approaches the region from
the southwest Thursday night into Friday expect rain chances to
increase. These showers and thunderstorms should spread southwest to
northeast across the region Friday morning followed by additional
chances along a cold front that sweeps across the area Friday
evening into the overnight.

Highs through the short term period will be in the 70`s at most
locations. Cooler near the lakeshore on Thursday. Lows each night in
the 50`s to lower 60`s.
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&&

.LONG TERM /SATURDAY THROUGH MONDAY/...
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Models continue to struggle with the timing of upper level ridging
over the southern Great Lakes over the weekend. The international
models are the most consistent with each other and have leaned that
direction for the forecast. So after some showers across the east on
Saturday it looks like the CWA may be dry until a cold front
approaches on Monday with an increased chance of thunderstorms.
Temperatures will continue to run above seasonal averages with highs
in the 70`s common. Lows mostly in the 50`s to near 60.
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&&

.AVIATION /06Z Tuesday THROUGH Saturday/...
Widespread VFR conditions are expected to continue through much
of this period with the exception of periodic diminished
conditions to MVFR in showers that develop. Currently a cold
front is located west of the area and will very slowly move east
before becoming near stationary this afternoon. This front slows
so much primarily due to an interaction with it and an upper
level trough/surface low over the western Ohio River Valley.
Much of the forcing needed for shower development will occur
when this low move east across the Ohio River Valley late today
into Wednesday, increasing the confidence in showers and
thunderstorms after this TAF period. There is consistency in
models that suggest some light showers will build north over the
area this afternoon into the evening, but they should remain
scattered in nature making it very difficult to pinpoint timing
for showers in the TAF. Opted to introduce VCSH/VCTS this
afternoon with -SHRA expected for most terminals after 00Z
Wednesday. If the boundary slows anymore, the chances of shower
development will be pushed even later and likely into the next
TAF period so will continue to monitor. With this update, only
opted to decreased KMFD to MVFR ceilings with lowering of cloud
decks expected as the low pushes closer to the area, but
confidence wasn`t high enough elsewhere. Cannot rule out brief
MVFR visibilities in the heaviest showers today as well.

Southwest winds of 5-10 knots will persist through this
afternoon before gradually shifting to become east-northeast
tonight. Overnight winds will be light and variable expect in
heavier showers/thunderstorms.

Outlook...Non-VFR possible in showers and thunderstorms Tuesday
night through Wednesday and again on Friday through Saturday.

&&

.MARINE...
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Southerly winds of 5 to 10 knots are expected through early
afternoon but are expected to shift around to the north as a
weakening cold drifts southward across the lake through the night.
These northerly winds may increase to 10 -20 knots which will build
waves to 2 to 4 feet. THe stronger winds appear to be focuses from
Willowick to the Toledo Harbor. This will be the region to monitor
for a short lived small craft advisory late tonight into Wednesday
morning. High pressure then ridges southward  across the lake into
Thursday evening with a continue northeast wind. This may end up
producing choppy conditions from Fairport to The Islands. Winds
swing around to the south on Friday as a warm front moves across the
region. Low pressure moves eastward across the southern Great Lakes
by Friday night with a weakening cold front crossing the lake.
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&&

.CLE WATCHES/WARNINGS/ADVISORIES...
OH...None.
PA...None.
NY...None.
MARINE...None.

&&

$$

SYNOPSIS...Campbell
NEAR TERM...Campbell
SHORT TERM...MM
LONG TERM...MM
AVIATION...Campbell
MARINE...MM