Area Forecast Discussion
National Weather Service Cleveland OH
944 AM EDT Tue Oct 28 2025
.SYNOPSIS...
High pressure currently resides over eastern Canada and will
build off to the east this evening. On Wednesday, a low
pressure system will move into the region from the southwest and
move northeast towards New England by the end of the week. Lake
effect rain showers will persist across the primary snow belt
through the weekend.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
In the mid/upper-levels, complex weather pattern evolution is
expected through sunset Wednesday evening. At 3:45 AM EDT this
morning, a high pressure ridge centered near James Bay extends
S`ward to our region, a low is centered just south of Nova
Scotia, and a trough is digging SE`ward over/near the northern
and central Rockies and Great Plains. The low near Nova Scotia
should retrograde W`ward to Lower MI by sunset Wednesday evening
as it gravitates toward the digging trough. Simultaneously, the
aforementioned trough will dig farther SE`ward toward the
southeastern United States as a potent jet streak initially west
of the trough`s axis translates initially SE`ward and
eventually rounds the base of the trough. Therefore, by sunset
Wednesday evening, a congealed and deep trough is expected to
reside over much of the United States and vicinity. In response,
the aforementioned ridge should retreat toward northern Quebec
and vicinity today through sunset Wednesday evening. At the
surface, the ridge continues to extend from Quebec into our
region today. Tonight through Wednesday, a trough will
overspread our region from the south and west. Within this
trough, one surface low should develop generally NE`ward from
the Lower MS Valley toward the southern Appalachians tonight
through Wednesday in association with focused divergence
aloft/MSLP falls associated with the left-front quadrant of the
aforementioned mid/upper-level jet streak. On Wednesday, a
separate low should develop in vicinity of the Carolinas via
low-level horizontal wind shear along the east coastal front and
as divergence aloft and attendant MSLP falls overspread that
area from the west, downstream of the mid/upper- level trough
axis.
This weather pattern evolution will allow NE`erly to E`erly
surface winds associated with net cool and dry air advection to
persist over our region. This advection regime at/near the
surface and stabilizing subsidence accompanying the retreating
ridge are expected to allow primarily fair weather to affect our
region through sunset Wednesday evening. However, the complex
low pressure system`s warm conveyor belt undergoing isentropic
ascent aloft while tapping into abundant moisture from the Gulf
and eventually the southern Gulf Stream, and the wet-bulb
effect, should allow scattered light rain to overspread our CWA
generally from the south early Wednesday evening, especially
roughly along and south of U.S. Route 30. Near-normal high
temperatures in the mid 50`s to near 60F are expected during the
late afternoon hours of today and Wednesday. In between, overnight
lows should reach mainly the lower 30`s to lower 40`s around
daybreak Wednesday.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
In the mid/upper-levels, the potent jet streak is expected to
translate generally NE`ward from the southeastern United States
toward the northeastern United States and Canadian Maritimes
during this time period. Strong horizontal wind shear associated
with the jet streak is expected to help form a 500 mb low over
the TN Valley by sunset Wednesday evening. Given the expected
evolution of the jet streak, the 500 mb low should wobble
NE`ward in vicinity of the spine of the Appalachians and to
southern Quebec during the short-term period. The track of the
aforementioned jet streak and focused divergence aloft/MSLP
falls associated with the jet streak`s left-front quadrant
should allow the aforementioned surface lows to congeal in
vicinity of the Carolinas and Delmarva Peninsula Wednesday night
through Thursday. The congealed surface low should then wobble
NE`ward in vicinity of the Mid-Atlantic and northeast United
States coast before reaching the Canadian Maritimes by nightfall
Friday evening as the low continues to deepen. Accordingly, the
above-mentioned surface trough is expected to linger over our
region. Given expected evolution of the weather pattern at the
surface and aloft, our regional surface winds should back
gradually from ENE`erly to W`erly during the short-term period,
which will allow our region to remain within the cold sector.
Accordingly, overnight lows should reach mainly the mid 30`s to
mid 40`s around daybreak on Thursday and Friday. Late afternoon
highs should reach the upper 40`s to mid 50`s on Thursday and
Friday.
As the low pressure system`s warm conveyor belt, including
TROWAL, continues to undergo isentropic ascent aloft while
tapping into abundant moisture from the Gulf and southern Gulf
Stream, widespread rain is expected to overspread our region
generally from the south Wednesday night and persist on
Thursday. Rain is expected to be steady to heavy at times
overnight Wednesday night through Thursday due to the
following: the release of weak potential instability via
frontogenetical convergence and moist ascent in the TROWAL;
lake-enhancement of precip via the seeder-feeder process and
weak to moderate lake-induced CAPE amidst a sufficiently-cold/moist
low/mid-level atmospheric column over ~14C Lake Erie. Lake-enhanced
rain should stream generally SW`ward from Lake Erie overnight
Wednesday night into Thursday morning and then stream generally
S`ward from the lake later Thursday as mean low-level flow backs
from NE`erly to N`erly. During Thursday night, the warm
conveyor belt and associated widespread rain should exit
gradually NE`ward. Accordingly, lake-enhanced rain should
transition to pure lake-effect rain (LER), heavy at times, as
mid-level moisture decreases and the seeder-feeder process
ceases, yet the low-level atmospheric column remains
sufficiently-cold/moist over/downwind of Lake Erie and
lake-induced CAPE probably remains at least weak to moderate.
During Thursday night, lake-enhanced/effect rain should stream
generally S`ward and then SE`ward from Lake Erie as mean
low-level flow backs from N`erly to NW`erly. On Friday, LER,
heavy at times, should stream generally SE`ward and then
ESE`ward across the snow belt of NE OH/NW PA and vicinity as the
mean low-level flow of sufficiently-cold/moist air backs
further from NW`erly to WNW`erly and lake-induced CAPE probably
remains at least weak to moderate. Outside of LER, scattered
rain showers are possible as a shortwave trough axis embedded in
NW`erly flow aloft is preceded by moist isentropic ascent.
&&
.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
W`erly to NW`erly flow aloft and embedded shortwave disturbances
will affect our region during the long-term period, which should
allow primarily surface troughing to affect northern OH and NW
PA. However, a narrow ridge at the surface and aloft should
advance E`ward across our area Sunday night. This weather
pattern at the surface and aloft will maintain a chilly air mass
across our region. Overnight lows should reach mainly the mid
30`s to lower 40`s around daybreak Saturday, Sunday, and Monday.
Daytime highs should reach mainly the mid 40`s to lower 50`s
this weekend and Monday. Isolated to scattered rain showers
accompanying shortwave disturbances aloft should impact our
region, especially Friday night through Sunday and again on
Monday. LER persists amidst at least weak lake-induced CAPE and
should oscillate over and downwind of Lake Erie as the passage
of each shortwave disturbance causes the mean low-level flow of
sufficiently-cold and moist air to vary between mainly W`erly
and SW`erly.
&&
.AVIATION /12Z Tuesday THROUGH Saturday/...
VFR is expected to continue through the TAF period with
occasional high-level cirrus streaming in from the southwest.
Otherwise, east winds around 6 to 8 knots increase to 10 to 15
knots with gusts as high as 20-25 knots late this morning
through late afternoon. There will be a bit of a wind gradient
with the stronger winds expected out west and lower winds
towards the east. Winds weaken to 6 to 10 knots overnight
tonight.
Outlook...Non-VFR expected in widespread periods of rain
Wednesday evening through Thursday night. Non-VFR will linger
across Northeast Ohio and Northwest Pennsylvania Friday through
the weekend with lake effect clouds and rain showers.
&&
.MARINE...
East-northeast flow is expected on Lake Erie through Thursday
morning as we remain sandwiched between high pressure over
Quebec and a developing low pressure over the southern portion
of the CONUS. Winds of 15 to 25 knots will likely weaken to
around 10 to 15 knots after daybreak before strengthening again
to 20 to 25 knots this afternoon through tonight. A Small Craft
Advisory is in effect for the nearshore waters of Lake Erie for
this period of stronger winds. Winds gradually weaken to 15 to
20 knots late tonight into early Wednesday.
The aforementioned low is expected to develop to around 1000 mb
as it moves northeast towards the mid-Mississippi Valley on
Wednesday and then possibly deepening to sub-1000mb as it
continues towards just south of Lake Erie by Thursday. As the
low approaches, east-northeast winds should strengthen to 20-25
knots by Wednesday night, and then 25-30 knots on Thursday.
Compared to previous forecasts, model guidance has trended
towards a weaker low, and thus a much lower chance of gale-force
winds (so gales are no longer in the official forecast right
now). As the low continues northeastward towards Ontario/Quebec,
winds become northwest Thursday night into Friday morning and
then westerly Friday afternoon through Saturday. These winds
are mostly likely to be around 25-30 knots late Thursday night
through early Friday night before dissipating thereafter.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...None.
PA...None.
MARINE...Small Craft Advisory until 4 PM EDT Wednesday for LEZ142>146.
Small Craft Advisory from 5 PM this afternoon to 2 AM EDT
Wednesday for LEZ147>149.
&&
$$
SYNOPSIS...23
NEAR TERM...Jaszka
SHORT TERM...Jaszka
LONG TERM...Jaszka
AVIATION...Saunders
MARINE...Saunders
