277
FXUS61 KCLE 171745
AFDCLE

Area Forecast Discussion
National Weather Service Cleveland OH
145 PM EDT Tue Jun 17 2025

.SYNOPSIS...
A warm front will lift north across the area today. Low pressure
will track through the Great Lakes region late Wednesday into
early Thursday dragging a cold front through the area. High
pressure will build in across the region this weekend into early
next week.

&&

.NEAR TERM /THROUGH WEDNESDAY/...
9:52 AM EDT Update...

Most of the forecast remains valid per latest trends in obs and
model guidance. A surface warm front continues to sweep NE`ward
across far-NE OH and is expected to move NE`ward across the rest
of our CWA through this early afternoon. This warm front will
usher-in a warmer and more humid air mass originating over the
Gulf. Isolated to scattered rain showers and isolated
thunderstorms remain possible through this early afternoon along
and behind the warm front due to moist isentropic ascent
releasing weak elevated instability along the upper-reaches of
the front and ahead of shortwave trough axes embedded in
cyclonic SW`erly flow aloft.

Made minor adjustments to POP`s this afternoon through early
evening based on latest trends in obs and model guidance. Still
expect the best potential for scattered showers and
thunderstorms during that time frame to be focused across
roughly the southeastern 1/3 of our CWA. This is where surface
trough axes accompanying the aforementioned shortwave trough
axes aloft and an expected Lake Erie lake breeze front
extending from far-NE Cuyahoga County through Erie County, PA
are expected to act as foci for surface-based convection
initiation. These lifting mechanisms are expected to release
weak to moderate boundary layer instability stemming from peeks
of sunshine and daytime heating of the warm/moist sector
boundary layer. Localized flash flooding remains a concern,
especially along the lake breeze front, since WSW`erly mean mid-
level flow of only 20 to 30 knots should exhibit a large
component parallel to the mesoscale front and permit training
and slow-moving showers/storms. Periods of heavy rain are
expected as PWAT`s remain unusually-high in/near the warm/moist
sector. Please see discussion below for further details.

Previous Discussion...

The near term forecast will bring warmer temperatures, muggy
conditions, and periodic chances for showers and thunderstorms
today though tomorrow. There are some isolated to scattered
showers this morning south of the Highway 30 corridor closer to
central Ohio. We anticipate the showers to become more scattered
to widespread later this morning into this afternoon. There
will be a few thunderstorms possible especially with the daytime
heating adding some energy in the atmosphere. Precipitable
water values will increase today up to 1.9 inches with the
passage of the warm front. With high moisture content, MLCAPE
values up to 1000 J/KG, weak shear and steering flow is a good
setup for showers and embedded storms to develop throughout the
day today. Some of these showers and storms may be efficient
rainfall producers with localized heavy rainfall possible today
into this evening. Organized strong or severe convection is not
expected today. The highest POPs will be generally from Marion
to Cleveland to Erie line and southeastward. Lower POPs will be
over northwest Ohio around the Toledo area. High temperatures
will range from the upper 70s to around 80 degrees where showers
and storms persist more across northeast Ohio and northwest
Pennsylvania. The warmest temperatures today will be over NWOH
with low to middle 80s.

Most of the diurnally driven convection will slowly end this
evening after sunset. We will keep some slight to chance POPs
overnight given the moisture rich atmosphere and some weak lift
lingering over the Upper Ohio Valley tonight. Wednesday will be
a little more interesting with the potential of some strong to
severe storms moving in late in the day and evening. A shortwave
trough will track from the Cornbelt region of the Midwest into
the Great Lakes region on Wednesday. A surface low pressure
system will develop and strengthen as it tracks through the
central Great Lakes region late Wednesday which will drag a cold
front across the Ohio Valley.

Ahead of this shortwave, there is a weak lead impulse wave in
the 500 mb flow that will track across Ohio around midday
Wednesday. Given the tropical like airmass and diurnal heating,
there could be a round of scattered showers and storms that
quickly move from west to east during the midday or early
afternoon on Wednesday. It does appear that if this lead weather
system kicks through, there will be enough time to quickly
destabilize the atmosphere again late afternoon into the evening
ahead of the approaching cold front. The short term discussion
will have more details about the severe weather potential
Wednesday evening. High temperatures on Wednesday will top out
in the lower to middle 80s areawide with very humid conditions.

&&

.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY NIGHT/...
Deepening upper level low pressure will be moving across Lower
Michigan Wednesday night while a surface low drags a cold front
towards the region. Ahead of the cold front MLCAPE values will
range from 1000-1500 J/kg with deep layer shear values near 30
knots. These environmental parameters will support upstream
organized convection ahead of the cold front. This convection is
expected to enter the I-75 corridor Wednesday evening.
Thunderstorms that do develop will be capable of producing
damaging wind gusts and severe hail with a chance for some
embedded tornadoes. Storms will push east across northern Ohio
Wednesday night with the cold front while decreasing in
intensity with the loss of daytime heating.

Some showers and thunderstorms will linger on Thursday before high
pressure gradually builds overhead Thursday night into Friday. Highs
in the mid to upper 70s behind the cold front will rise into the low
to mid 80s by Friday. Overnight lows settle in the lower 60s on
Thursday night with warm overnight lows in the upper 60s to lower
70s by Friday night.

&&

.LONG TERM /SATURDAY THROUGH MONDAY/...
Large scale ridging builds across the region through the long term
period. Main weather concern will be above normal temperatures
forecasted to rise into the upper 80s to lower 90s by the weekend.
Heat indices may approach 100 degrees Sunday and Monday. Maintained
slight chance PoPs to begin the weekend as a shortwave aloft moves
overhead.

&&

.AVIATION /18Z Tuesday THROUGH Sunday/...
Mix bag of conditions are being observed across the area this
afternoon as showers and thunderstorms have begun to develop.
Within these storms, heavy rain remains the primary concern and
showers have had a history of reducing visibilities to as low as
3/4SM. Initial impacts to terminals will be KMFD, KFDY, and KCLE
before portions of the east CWA fill in as well. Given the
scattered nature of these storms, opted to handle the reduced
visibilities and weather aspect as TEMPOs through around 00Z
this evening.

After sunset, reduction in instability will allow for the bulk
of showers to dissipate and most terminals to rebound to VFR
into the early morning hours on Wednesday. There is a potential
for patchy fog/low stratus to develop for inland terminals, so
opted to reduce those terminals to MVFR/IFR around 08Z to
daybreak for the impacted terminals. The terminals along the
lakeshore may briefly have reduced ceilings, but confidence is
low there so opted to not include it with this update. By mid to
late Wednesday morning, showers and thunderstorms will once
again develop across the area and pose the potential for reduced
conditions to MVFR and IFR across the area. Opted to handle the
bulk of this potential with PROB30. The more notable impact to
terminals is expected to occur Wednesday evening as a decaying
QLCS pushes across the area.

Winds will remain from the southwest through the duration of
this TAF period. Winds this afternoon will be 5-12 knots with
the strongest winds and localized gusts up to 20 knots at
terminals receiving showers. Overnight winds will weaken to
around 5 knots before again increasing from the southwest in the
afternoon.

Outlook...Non-VFR likely with scattered to periodic showers and
thunderstorms Wednesday through Thursday. The best chance of
thunderstorms will be Wednesday evening into early Thursday
morning. There is a small chance of isolated thunderstorms
Friday afternoon and Saturday afternoon over far northeast Ohio
and northwest Pennsylvania.

&&

.MARINE...
Low pressure moving east from Ontario to Quebec has lifted a
warm front north of the lake, allowing for southwest winds of 10
to 15 knots to become established. These winds will persist into
Wednesday evening before increasing from the southwest to 15-20
knots Wednesday evening into the overnight hours ahead of an
approaching cold front. This increase in winds may need a short
duration Small Craft Advisory Wednesday into Thursday, but will
continue to monitor trends in the winds for better detail on
that potential. Behind the cold front Thursday night, winds will
weaken from the west-southwest at 5-10 knots through Saturday
morning. Another warm front will lift north on Saturday, briefly
increasing winds from the southwest to 10-15 knots Saturday
afternoon. After that, winds will return to 5-10 knots but
persist from the southwest. Given the prolonged southwest flow,
waves along the southern lakeshore should remain 2 feet or less
with the exception of when the cold front pushes east. During
that time, waves may increase to 3-5 feet across central and
eastern basins.

&&

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

&&

$$

SYNOPSIS...77
NEAR TERM...77/Jaszka
SHORT TERM...13
LONG TERM...13
AVIATION...04
MARINE...04