Area Forecast Discussion
Issued by NWS Cleveland, OH

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297
FXUS61 KCLE 081108
AFDCLE

Area Forecast Discussion
National Weather Service Cleveland OH
708 AM EDT Mon Jul 8 2024

.SYNOPSIS...
High pressure will continue to influence the region as it moves to
New England today. The remnants of Beryl will approach the local
area Tuesday night into Wednesday and interact with a southward
moving frontal boundary. The remnant low will continue
northeast into Canada on Thursday.

&&

.NEAR TERM /THROUGH TUESDAY/...
Surface high pressure over western New York will continue east to
New England today. The airmass will remain dry with increasing high
level clouds. Temperatures at 925mb warm by 1-1.5C from yesterday
with highs forecast to also trend upwards into the upper 80s to
lower 90s. The pressure gradient remains weak enough that lake
breezes are once again forecast to develop along the northeast
lakeshore so look for highs to occur by midday in those areas.

The upper level trough on water vapor imagery approaching the
Midwest will only make slow eastward progress through the near term.
Meanwhile we will continue to watch the remnants of Beryl move north
across eastern Texas. Models depict a good piece of shortwave energy
riding northeast ahead of the trough tonight with prolonged
southwesterly flow and moisture advection increasing, especially
into western portions of the area. Kept a low pop in the
forecast across NW Ohio after about 4 AM tonight. A slow moving
cold front does push south across lower Michigan on Tuesday but
the better frontal forcing does not really get into here until
Tuesday night. We do see some tightening of the baroclinic zone
as Beryl approaches and will carry a low chance of showers and
thunderstorms across much of the area Tuesday afternoon. The
best low level convergence may be across NE Ohio where the lake
breeze may be slightly enhanced by winds starting to veer in
advance of tropical remnants. Instability does range from
500-1200J/kg but the lack of forcing is still expected to limit
coverage.

&&

.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/...
The remnants of Beryl will be the big story of the midweek period,
with the potential for some much needed rainfall to help ease
ongoing drought conditions, as well as a few strong to severe
storms. However, some uncertainty in the exact track and therefore
impacts to the local area remain.

Regarding the details, Beryl is making landfall on the central Texas
coast as a category 1 hurricane this morning. A large mid/upper
longwave trough to the north of Beryl stretches from southern Canada
through the central and southern Plains in between strong mid/upper
ridges over the Intermountain West and SE CONUS. This pattern is
creating broad southwesterly deep layer flow from the Texas and
Louisiana Gulf coasts through the Ohio Valley and southern Great
Lakes which will steer the remnants toward the region Tuesday night
and Wednesday. The key interaction between Beryl`s remnant low and
the broad trough will be an embedded mid/upper shortwave that will
lift from the Lower Mississippi Valley Tuesday night into the
vicinity of southern Ontario and Lake Huron by Wednesday night
before departing through eastern Ontario and Quebec Thursday and
Thursday night. This shortwave track is fairly consistent among
deterministic and ensemble guidance, but timing in which it picks up
and phases with Beryl`s remnant low remain a little uncertain which
results in displacements of the surface low track either a bit
farther west or a bit farther east. Consensus points toward the
surface low (Beryl`s remnant low) tracking through NW Ohio Wednesday
and Wednesday evening, but as stated, there is room for it to be a
bit farther west or east. A track through NW Ohio would put the
heaviest and steadiest swath of QPF across Indiana and Michigan, and
this is reflected in WPC QPF forecasts, but given deep tropical
moisture advecting northward Tuesday night and Wednesday, all of the
CWA will see at least some rain, with pockets of heavier rain
wherever convection can develop.

As Beryl`s remnant surface low begins to deepen and lift out of the
Mississippi Valley Tuesday night in response to phasing with the
mid/upper shortwave, the weak frontal boundary draped across the
region will lift back north as a warm front. Deep moisture advection
with PWATs exceeding the daily record per the NAEFS Ensemble
Situational Awareness Table (over 2 inches) will undergo isentropic
ascent along and north of the retreating warm front Tuesday night
into Wednesday morning, likely resulting in a band of moderate to
heavy rain lifting across the region. This should give all areas
some rain before we get into the warm sector and attendant dry slot
Wednesday afternoon, so have likely PoPs spreading northeastward
Tuesday night and Wednesday morning. Coverage of precip is the
biggest question mark Wednesday afternoon and evening in the warm
sector as the surface low lifts into NW Ohio and continues to
deepen. Pattern recognition suggests scattered coverage along with
peaks of sunshine, and that could create a problem with scattered
strong to severe convection developing in response to diurnal
destabilization. The latest NAM forecast soundings suggest MLCAPE
exceeding 1500 J/Kg Wednesday afternoon, and over 2000 J/Kg SBCAPE
along with impressive speed and directional shear yielding 50 knots
of deep layer effective bulk shear and curved hodographs. This makes
sense given the circulation nearby, so odds appear to be increasing
for the initiation of deep convection Wednesday afternoon and
evening that could rotate, especially in NE Ohio and NW PA where the
best destabilization is expected. LCL heights will easily be below
1000 m given the moist environment, so a few tornadoes are possible.
The SWODY3 marginal risk looks reasonable for NE Ohio and NW PA, and
will need to see the ultimate track of the surface low to determine
how much coverage of severe storms there could be, but again, odds
are increasing for at least a few rotating storms. Any convection
will contain torrential rainfall rates Wednesday afternoon and
evening with PWATs still around 2 inches and deep, warm cloud
layers, and this could cause rate driven flash flooding wherever
the convection develops. Moderate (D1) drought conditions continue
up the I-71 corridor from roughly Mansfield to Cleveland, but some
areas to the west and east of there have improved over the past 2
weeks. Given the likelihood for scattered coverage Wednesday, can`t
promise that all areas will see a lot of rain, but everyone should
see enough to somewhat ease the dryness. High rainfall rates could
still cause localized flooding in the drought areas.

As the low exits across Ontario Wednesday night and Thursday, the
trailing cold front will sweep across the region allowing for drying
from west to east, but wraparound moisture and a lingering surface
trough will keep a few scattered showers going through Thursday, but
no more heavy rain is expected. Surface ridging will finally build
in Thursday night for completely dry conditions.

Highs will range from the upper 70s to low 80s Wednesday and
Thursday with lows in the upper 60s to around 70 Tuesday night and
mid to upper 60s Wednesday night and low to mid 60s Thursday night.

&&

.LONG TERM /FRIDAY THROUGH SUNDAY/...
Broad mid/upper troughing lingering across the Great Lakes Friday
will slowly lift out Saturday and Sunday allowing the massive heat
ridge over the Intermountain West to expand east into the Plains and
Midwest. Some degree of WNW flow looks to linger across the Great
Lakes through the weekend keeping the highest heat out toward the
Plains, but there will certainly be a warming trend Friday through
Sunday. The old frontal boundary lingering near the Appalachians and
Mid Atlantic could bring some widely scattered diurnal convection
Friday and Saturday, but most areas will stay dry with the
increasing heights aloft. Will need to watch for some convection
spilling over the ridge in the WNW flow by Sunday as a frontal
boundary sets up across the lakes on the NE periphery of the heat,
but kept PoPs at slight chance this far out.

Highs in the low/mid 80s Friday will warm into the mid/upper 80s
Saturday and upper 80s/low 90s Sunday.

&&

.AVIATION /12Z Monday THROUGH Friday/...
High pressure will move to New England today while continuing to
influence the region. The airmass is generally dry with
increasing cirrus(high cloud) and VFR conditions. Winds will be
light and variable at TAF issuance, then southwesterly at 5-7
knots after 15Z. The exception is near Lake Erie where CLE/ERI
and eventually YNG will experience a wind shift to the north.
Light winds are expected again tonight. Moisture will increase
in NW Ohio after 06Z with ceilings lowering. Can not entirely
rule out an isolated shower reaching TOL before the end of the
TAF period but the likelihood is too low to include in the
forecast.

Outlook...Non-VFR possible in isolated to scattered showers and
thunderstorms on Tuesday. Non-VFR becoming more likely in
widespread showers with scattered thunderstorms associated with
the remnants of Beryl late Tuesday night into Wednesday.
Lingering non-VFR is possible on Thursday with isolated to
scattered showers and thunderstorms.

&&

.MARINE...
Quiet conditions will continue on Lake Erie today and Tuesday with
light winds, but the remnants of Beryl approaching from the
southwest Tuesday night and Wednesday will lead to increasing winds
and waves. E winds will increase to 10-15 knots Tuesday night, with
ENE winds of 15-20 knots Wednesday. This will build 2 to 4 foot
waves in the western and central basins, so Small Craft headlines
may be needed by Wednesday. Winds will shift to the NW Wednesday
night behind the remnant low as speeds stay around 15-20 knots, and
this will push the 2 to 4 foot waves into the central and eastern
basins before winds turn W and decrease to 10-15 knots Thursday. SW
winds will then decrease to 5-10 knots by Friday.

&&

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

&&

$$

SYNOPSIS...KEC
NEAR TERM...KEC
SHORT TERM...Garuckas
LONG TERM...Garuckas
AVIATION...KEC
MARINE...Garuckas