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434
FXUS61 KCLE 141736
AFDCLE

Area Forecast Discussion
National Weather Service Cleveland OH
136 PM EDT Tue May 14 2024

.SYNOPSIS...
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.

&&

.NEAR TERM /THROUGH WEDNESDAY/...
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1:30 PM Update...
Isolated to scattered showers expected today and tonight.
Kept isolated thunder in the forecast for now but there`s a good
chance that gets removed with the next update as cloudy skies
prevent much instability from developing. Confidence is increase
for greater coverage in rain along and east of I-77 Wednesday
afternoon, so have increased PoPs. If models remain consistent,
may be able to add an area of >80% PoPs.

Previous Discussion...
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/...
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.

&&

.LONG TERM /SATURDAY THROUGH MONDAY/...
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.

&&

.AVIATION /18Z Tuesday THROUGH Sunday/...
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VFR remains prevailing at most sites, although some MVFR
ceilings have surprisingly made it up to KFDY and KMFD from the
south. These ceilings are lower than model guidance suggest, so
there is some uncertainty with how long though MVFR ceilings
last. Otherwise, isolated to scattered rain showers are
expected this afternoon. Cloud cover increases with widespread
MVFR from the south tonight. Many models are have IFR conditions
late tonight into Wednesday morning, especially for southern and
eastern TAF sites. Only added IFR to KYNG for a few hours where
confidence was highest but will have to watch KCAK and KMFD as
well. Isolated to scattered rain showers continue tonight.

For Wednesday, ceilings gradually improve to MVFR and then VFR
from the north and west by the afternoon. Confidence in rain
showers is increasing, especially for southern and eastern TAF
sites (especially KYNG and KCAK). There is a very low
probability of isolated thunderstorms, but mainly at or after
18Z Wednesday afternoon.

Southeast winds of 5-7 knots this afternoon will become 5-10
knots out of the northeast tonight and Wednesday.

Outlook...Non-VFR possible showers and thunderstorms Thursday
night through Saturday.
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&&

.MARINE...
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.

&&

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

&&

$$

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