081
FXUS61 KCLE 092349
AFDCLE

Area Forecast Discussion
National Weather Service Cleveland OH
749 PM EDT Sun Aug 9 2026

.WHAT HAS CHANGED...
A Severe Thunderstorm Watch has been issued for the western half
of the forecast area through midnight tonight. Primary hazard
will be damaging wind gusts, a tornado or two, and heavy
rainfall.

Timing of thunderstorms into Northwest Ohio this evening has
trended faster and the Slight Risk for severe thunderstorms
(level 2 of 5) has been expanded east to around Vermilion.
Raised low temperatures slightly the next couple nights given
the warm and humid airmass. Lowered pops on Tuesday morning and
portions of the area Tuesday afternoon given uncertainty in
timing and coverage of showers and thunderstorms. QPF has also
trended down across northeast portions of the forecast area
through Wednesday.

&&

.KEY MESSAGES...
1) There is a Slight Risk (level 2 of 5) of severe thunderstorms
in Northwest Ohio this evening and tonight. Damaging wind gusts
of 50-60 mph are the primary hazard.

2) Additional rounds of showers and thunderstorms through Wednesday
will lead to the potential for localized flooding and scattered
severe thunderstorms.

3) Muggy conditions will make temperatures feel uncomfortable at
times through Wednesday with cooler and drier air returning to end
the week.

&&

.DISCUSSION...
KEY MESSAGE 1...
7:50 PM Update...
An MCS is ongoing and moving roughly east-southeast across
northern Indiana into Northwest Ohio this evening. The MCS has
maintained strength as moving east with SPC issuing a Severe
Thunderstorm Watch for the western half of the forecast area
through midnight tonight. Primary hazard will be damaging wind
gusts and a tornado or two. Can`t rule out instances of heavy
rainfall with isolated flash flooding, particularly in urban and
well-saturated areas.

Previous discussion...
Weak low pressure is located over NW Illinois with a warm front
extending east across northern Indiana into western Ohio. The
warm front is identified primarily by a swath of dewpoints in
the lower 70s that is advecting northward today. An MCS is
ongoing across Lake Michigan this afternoon and a Severe
Thunderstorm Watch extends as far east as Williams County Ohio
through 7 PM. The northern portion of the MCS is expected to
outpace the reservoir of unstable air and the associated
moisture advection. The southern portion of the MCS is more
likely to maintain strength into Indiana but unclear at this
time the extent it can hold together into NW Ohio. The
instability gradient is expected to lift north along the I-75
corridor and possibly to the central highlands but only make
slow progress to the northeast across Lake Erie tonight. CAMS
have struggled with the handling of this MCS but best timing
estimates are for a few thunderstorms to continue east along the
advancing warm front into the I-75 corridor and possibly
towards Mansfield between 8-11 PM. A general weakening trend is
likely as we get past sunset and uncertainty remains regarding
the coverage of severe wind gusts into this evening. In general
the timing of thunderstorms has trended faster into NW Ohio.

Later tonight we expect to see a low level jet develop from Chicago
into lower Michigan. This feature combined with the next round of
shortwave energy moving through the quasi northwest flow aloft are
likely to result in a rejuvenation of thunderstorms upstream across
SW lower Michigan. Showers with scattered thunderstorms are expected
to spread east across Lake Erie after midnight tonight while perhaps
more robust convection still favors a southeast trajectory towards
Central Ohio. Models over the last couple days have been
highlighting a swath of heavier rain setting up just southwest of
our forecast areas in Indiana/west central Ohio prior to 12Z.

KEY MESSAGE 2...
The local area remains on the downstream side of an
upper level ridge over the Rocky Mountains and Plains states through
mid-week. This places the local area in a favorable region for
additional rounds of showers and thunderstorms as the warm front
stalls in the vicinity and multiple shortwaves move through the
flow aloft. Timing of additional showers and thunderstorms is
challenging beyond tonight and will be impacted by storm
evolution, outflow boundaries, and placement of the stalled
front. We do expect a break during the late morning/early
afternoon on Monday. Moderate instability is expected to
develop through the afternoon, especially across southern
portions of the forecast area, with scattered thunderstorms
possible during the late afternoon. A more organized severe
weather threat could materialize during the evening ahead of a
more substantial shortwave trough sliding through the Central
Great Lakes. Good veering of the flow with height is expected
along with around 40 knots of shear. Almost all of the forecast
area is in a Slight Risk(level 2 of 5) for severe thunderstorms
on Monday.

Depending on storm evolution, a trailing rain threat could linger
into Monday night, particularly closer to Central Ohio. With the
potential for a stronger round of storms on Monday evening/night,
did lower pops to chance for most of the daytime on Tuesday.
The airmass remains very moist with PW values rebounding to near
2 inches but confidence in placement of storms is low by this
time. The more active storm track could be just south of the
area on Tuesday but will need to be monitored. Coverage is
likely to increase again Tuesday night. Then one more
opportunity for thunderstorms is in the forecast on Wednesday
afternoon ahead of the eventual cold front. Storm total rainfall
amounts through Wednesday are over 2 inches across southwest
portions of the forecast area but could see localized totals of
3 or more inches over several days. Will need to monitor the
potential for flooding as the week progresses and areas become
saturated.

KEY MESSAGE 3...
This active stretch of weather will be characterized by warm
and muggy conditions. Dewpoints return to the 70s on Monday and
heat index values will be near 90 degrees across portions of
northwest and north central Ohio. Elevated humidity levels will
continue (at least in Ohio) through Wednesday. Temperatures
will settle back into the 70s to end the week and bring some
relief from the higher humidity.

&&

.AVIATION /00Z Monday THROUGH Friday/...
A cluster of strong to severe thunderstorms is knocking on the
doorstep of eastern terminals with the 00Z TAF issuance.
Maintained TEMPO groups for TSRA impacts at KTOL/KFDY between
00Z/Mon and 03Z/Mon. Confidence in the MCS maintaining its
strength as it moves east-southeast towards central Ohio
terminals remains low, but kept PROB30 groups in all of TAF
sites excluding KYNG/KERI. There will likely be future AMDs
as tonight evolves. Strong wind gusts to 35-40 knots will be
possible in strongest thunderstorms. Any severe thunderstorm
that moves over a terminal will be capable of producing 50+ knot
wind gusts. Highest confidence in severe wind gusts will be at
KFDY this evening.

Beyond the next 6 hours or so, the forecast gets very uncertain.
Guidance is continuing to suggest another area of showers and
thunderstorms moving across terminals Monday morning, possibly
into later Monday morning. However, exact details in timing and
location are hard to parse out at this time given ongoing
convection across the airspace. Given low confidence, opted to
maintain PROB30 groups for a few hours across all TAF sites for
any TS impacts Monday morning. Conditions are expected to remain
VFR outside of any SHRA/TSRA.

Outlook...Periods of non-VFR conditions are expected through
Thursday as several rounds of scattered showers and
thunderstorms move across the airspace. Some storms could be
strong to severe during this timeframe.

&&

.MARINE...
A warm front will lift across Lake Erie tonight, waiver across the
southern Great Lakes through at least part of Wednesday, and then
sag south late Wednesday or Wednesday night. Winds will shift
southwest behind the front tonight and remain generally west-
southwest until the cold front sinks south later this week. Winds
will be a bit elevated at 10-15kt late tonight through Monday
evening, pushing waves to 1-3 feet in the central and eastern
basins. Clusters of storms moving over or near the lake and their
mesoscale impacts to pressure and winds may cause a period or two of
more enhanced winds to 20kt or so over the lake, particularly late
tonight into Monday morning. This could lead to a brief period of 3
to 5 footers across parts of the central or eastern basin. Given the
convective influence on the pattern, confidence in a period of winds
closer to 20kt and/or waves of at least 4 feet is too low for any
headlines, though the potential for a brief period of Small Craft
Advisory/Beach Hazard Statements will continue to be evaluated.
Winds may briefly turn more northerly early Tuesday as the front
briefly pushes south before wavering back north. Winds will be a
bit elevated (at least 10 to 15kt, and perhaps briefly up to 20kt)
out of a more northerly direction behind the front Wednesday night
through Friday, bringing a period of choppier conditions.

&&

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

&&

$$

DISCUSSION...10/13
AVIATION...13
MARINE...Sullivan