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382
FXUS61 KCLE 151717
AFDCLE

Area Forecast Discussion
National Weather Service Cleveland OH
117 PM EDT Tue Jul 15 2025

.SYNOPSIS...
Weak high pressure builds across the area today before it departs to
the east tonight. A warm front will lift north across the area
tonight into Wednesday morning, lingering across the central
Great Lakes region Wednesday night and Thursday. A low moving
across the Great Lakes will bring a cold front south through
the area Thursday into Friday.

&&

.NEAR TERM /THROUGH WEDNESDAY/...
Weak high pressure continues to remain over the forecast area
today, with patchy fog expected early this morning across east-
central Ohio and Northwest Pennsylvania. Any fog that develops
should quickly dissipate after sunrise.

High pressure should move off to the northeast later this
evening into tonight. The stationary front that lingered south
of the area will lift northward as a warm front in response to
an upper-level trough and associated surface low moving into
the Midwest region. Meanwhile, a compact shortwave trough will
move in from the southwest, just behind the warm front. Forcing
from the trough, along with a humid airmass, will initially lead
to scattered showers and thunderstorms very early Wednesday
morning, with storm coverage expanding northeastward through
the morning. As weak-to-moderate afternoon instability builds,
should see coverage of showers and storms further expand,
especially east of a Sandusky-Marion line. PoPs in the 70-80%
range are forecast for Wednesday afternoon.

Substantial moisture will accompany this system, with HREF mean
PWATs peaking in the 2-2.1" range. Climatologically, this is
exceptional, with sounding climatology from PIT/ILN both showing
average daily max values in the 1.95-2" range (so we are above
the typical climatological max for mid-July). Soundings from
the 00Z NAM show skinny CAPE with very moist profiles. These are
good indicators that efficient, heavy rainfall will accompany
thunderstorms. Corfidi vectors vary (5-25 knot range) but are
generally lowest in the early to mid-afternoon, indicating at
least some potential for backbuilding. HREF/REFS have low to
medium (10-30%) probabilities of greater than 3" for much of the
area east of Sandusky-Marion, which is usually a really good
indicator for at least isolated to scattered flash flooding.
With all of these signals, have coordinated an expansion to the
WPC Day 2 ERO to include much of this area in Slight Risk for
Excessive Rainfall. Localize flash flooding is most likely in
the urbanized corridors (Cleveland-Akron-Canton-Youngstown
regions).

High PWATs, modest forcing, and low-medium instability will
likely also support an isolated microburst potential Wednesday
afternoon as well. However, marginal deep layer shear (HREF
mean around 15-20 knots) will likely prevent a more organized
severe weather potential. It is worth noting that the HREF does
have have a few updraft helicity tracks, with 10% contours east
of I-71.

&&

.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY NIGHT/...
By Wednesday night, the primary forcing mechanism (i.e. the
shortwave trough) will make its way east. However, many CAMs
continue thunderstorms with heavy rain and a low flash flood
risk through Wednesday night, mainly in the far eastern extents
of our forecast area.

Most models have the upper-level trough/low that moves into the
Great Lakes region approaching our forecast area on Thursday.
Additional showers and thunderstorms are expected on Thursday
with PoPs in the 70-90% range (mainly for the afternoon), with
the highest PoPs in the southern portion of our forecast area.
It`s likely there is another low end risk for severe weather and
localized flash flooding but the details are a little muddy at
this point as there is a good deal of model spread/uncertainty.

Model consensus is for the cold front associated with the low to
sweep through Thursday night into Friday. Low PoPs remain the
forecast Friday largely due to uncertainty in frontal timing,
but the expectation is for most of the day to be dry, with much
cooler temperatures - high temperature forecast is for highs in
the upper 70s! High pressure will build in overhead Friday
night with good bonfire weather in store.

&&

.LONG TERM /SATURDAY THROUGH MONDAY/...
Cool, quiet weather doesn`t last very long as high pressure
departs to the east on Saturday and we start to build warm,
moist air back into the region behind the departing high,
although certainly not as bad as it has been (we have highs in
the mid 80s with dew points in the upper 60s to low 70s right
now). Scattered showers and thunderstorms return Saturday
evening and Saturday night, with a better chance for areawide
storms on Sunday as a weak low moves across the Great Lakes
region. Its associated cold front is projected to move south
across the area Sunday night into Monday, though this is a day 7
forecast in July, that could very well change.

&&

.AVIATION /18Z Tuesday THROUGH Sunday/...
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VFR across the TAF sites early this afternoon with deterioration
to non-VFR likely from west to east in showers and thunderstorms
Wednesday morning into the afternoon. Coverage will begin as
isolated to scattered Wednesday morning, increasing to scattered
and perhaps widespread by Wednesday afternoon. Torrential rain
will accompany the showers and thunderstorms which will drop
vsbys down to IFR and perhaps as low as LIFR at times. Also cant
rule out some gusty winds in the strongest storms around 30 to
perhaps 40 knots.

Apart from a northwest to north lake breeze of 5 to 10 knots T
CLE/ERI, winds are generally light and variable early this
afternoon, 5 knots or less. Light and variable winds will
persist overnight before favoring a south to southwest
direction late Wednesday morning and afternoon, 5 to 10 knots.

Outlook...Non-VFR likely in scattered to widespread showers and
thunderstorms Wednesday afternoon and evening. Non-VFR possible
in lingering showers and thunderstorms across the south and
southeast portion of the area Thursday afternoon and evening.
VFR expected Friday before Non-VFR chances return Saturday and
Sunday in scattered showers and thunderstorms.
-- End Changed Discussion --

&&

.MARINE...
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Main concern for the marine period will be on Thursday as a cold
front crosses Lake Erie, ushering in west to northwest winds of
15 to 20 knots. Confidence is increasing for waves of 3 to
perhaps 4 feet across the central and eastern basins. Just short
of Small Craft Advisory at this time, but will continue to
monitor trends. Otherwise, flow across Lake Erie is expected to
be 10 knots or less. Thunderstorms will impact Lake Erie
Wednesday afternoon and evening which could produce gusty
winds. Additional chances for thunderstorms impacting Lake Erie
will return for the weekend.
-- End Changed Discussion --

&&

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

&&

$$

SYNOPSIS...Saunders
NEAR TERM...Saunders
SHORT TERM...Saunders
LONG TERM...Saunders
AVIATION...Kahn
MARINE...Kahn