033
FXUS61 KCLE 311917
AFDCLE

Area Forecast Discussion
National Weather Service Cleveland OH
317 PM EDT Sun Aug 31 2025

.SYNOPSIS...
High pressure will slowly drift offshore of New England by
Tuesday. A strong cold front moving into the Upper Midwest
Wednesday will cross the southern Great Lakes region Thursday
morning. Another cold front will cross the region Friday night
as a trough remains across the Great Lakes.

&&

.NEAR TERM /THROUGH MONDAY NIGHT/...
Quiet weather will continue through Labor Day along with a
warming trend as the large surface ridge of Canadian high
pressure centered over the central and southern Great Lakes this
afternoon slowly drifts across the eastern Great Lakes. This
will maintain mostly clear and cool conditions, but airmass
modification during the day Monday characterized by 850 mb
temps increasing to 9 to 10 C will allow highs to warm into the
mid/upper 70s in north central and NW Ohio, with low to mid 70s
lingering in NE Ohio and NW PA. A beautiful day for outdoor
festivities! Continued to lean on the colder side for low
temperatures tonight utilizing the NBM25th percentile given the
very dry airmass with clear skies and light winds, so expect
lows to fall into the upper 40s to low 50s in many areas again,
with pockets of low to mid 40s along U.S. 30 and in sheltered
areas of interior NE Ohio and NW PA. This will yield a chilly
morning start before the beautiful day to follow. Lows Monday
night should be a little milder as the high departs, with
generally low to mid 50s, except for some upper 40s in the same
sheltered areas again.

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
Heights will briefly rise across the eastern CONUS Tuesday as
mid/upper shortwave ridging attempts to build into the Great
Lakes ahead of another potent mid/upper trough and associated
cold airmass diving toward the northern Plains. This will kick
start warm air advection, allowing highs to reach the mid/upper
70s areawide, with parts of NW Ohio perhaps touching 80. Warm
air advection and associated southerly flow will further
increase by Wednesday as the trough and strong cold front
progress into the Upper Midwest, so most of the area will reach
the upper 70s to near 80, which is finally around normal for
early September. Lows will be moderating in this warm air
advection pattern as well, with generally low to mid 50s
Tuesday night and mid to upper 50s Wednesday night.

Dry weather will continue through much of Wednesday, but
increasing synoptic forcing from the combination of isentropic
ascent and moisture advection will bring some scattered showers
into the region by Wednesday evening. The better chance will
come with the cold frontal passage late Wednesday night into
Thursday, when the right entrance of an 80-100 knot H3 jet
streak lifting into Lower Michigan will create tight
frontogenesis, supporting a band of pretty steady showers along
and ahead of the front. NBM POPS gradually increasing to chance
Wednesday evening and likely to categorical Wednesday night
into Thursday look reasonable since all areas will see some
rain. At this point, a lack of deeper Gulf moisture and the
overnight/early morning frontal passage will prevent a severe
weather threat, but some embedded thunder will likely accompany
the heavier showers given the degree of forcing and at least
some weak elevated instability.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
The cold front is trending slightly slower Thursday in terms of
how quickly it moves east of the region, so lingering forcing
will allow showers to persist through much of the day in NE Ohio
and NW PA, so the categorical NBM POPS look reasonable in
eastern areas. Drier air Thursday night and Friday should mostly
dry out all areas behind the first front, but as the
impressively deep mid/upper trough digs from the Upper Midwest
through the Great Lakes Friday night and Saturday, a secondary
cold front will progress through the region. This will bring the
truly anomalous cool air, with 850 mb temps potentially dipping
below 3 C by Saturday night. Showers with this secondary frontal
passage will transition to lake-effect east and northeast of
Lake Erie. Early indications suggest SW flow through early
Saturday keeping the bulk of the lake-effect showers over
western NY, but veering boundary layer flow by Saturday
afternoon and Saturday night should bring showers in far NE Ohio
and NW PA, so added chance POPS in those areas Saturday and
Saturday night before drying out Sunday as surface ridging
builds in.

As touched on above, this will be another unseasonably cold shot
of air. A strong and persistent +PNA pattern and associated
sharp mid/upper ridge from the west coast of the U.S. up into
Alaska will allow the downstream mid/upper longwave trough to
carve out across all of central and eastern North America, with
a closed low pinwheeling near Hudson Bay. This sets up a winter-
like cross polar flow, with next weekend`s airmass originating
in the arctic. Luckily it is September and not January, but this
will lead to temperatures of at least 10-15 degrees below
normal next weekend. Highs in the upper 60s to around 70
Thursday and Friday will fall into the mid/upper 60s Saturday
and Sunday, with some areas of NE Ohio and NW PA possibly
staying in the low 60s Sunday. Overnight lows will be in the 40s
again in many areas away from the lake by the weekend.

&&

.AVIATION /18Z Sunday THROUGH Friday/...
Widespread VFR conditions are being observed this afternoon as
an areas of diurnal cu has developed and began to push inland
across northern Ohio due to weak lake breeze developing. These
ceilings remain scattered between 4 to 6kft which is expected to
persist through sunset. Winds across the area will persist from
the northeast at 5-10 knots through this evening before
becoming light and variable overnight. Late tonight/early
Monday morning, there is a non-zero potential for patchy
fog/mist to develop, especially within the valleys, however
given very low confidence of extent of the fog/mist, opted to
maintain VFR for all terminals through the period. Any fog/mist
that does develop will quickly dissipate after sunrise. Near
the end of this period, VFR conditions will continue as
northeast winds increase a bit to be sustained between 5-10
knots.

Outlook...VFR conditions are expected through Tuesday. On Wednesday,
isolated to scattered rain showers and thunderstorms with non-VFR
are possible.

&&

.MARINE...
High pressure will continue to influence the weather across
Lake Erie through Wednesday, allowing for calm marine conditions
to persist. Winds will be variable at 5-10 knots until Wednesday
when winds will become sustained from the southwest at 10-15
knots ahead of an approaching low pressure. On Wednesday night,
the aforementioned low pressure will move east across the
northern Great Lakes region, eventually moving a cold front east
on Thursday. Winds ahead of the boundary will increase to 15-20
knots. These winds will become west-northwesterly behind the
boundary at 15-25 knots. During this period behind the boundary,
waves along the nearshore may build to 3-5 feet. This period
will likely need marine headlines as conditions may be dangerous
to both swimmers and mariners. Calm conditions return by Friday
before another system potential bring hazardous marine
conditions to Lake Erie this weekend.

&&

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

&&

$$

SYNOPSIS...Garuckas
NEAR TERM...Garuckas
SHORT TERM...Garuckas
LONG TERM...Garuckas
AVIATION...04
MARINE...04