538
FXUS61 KCLE 270137
AFDCLE

Area Forecast Discussion
National Weather Service Cleveland OH
937 PM EDT Fri Jul 26 2024

.SYNOPSIS...
High pressure will gradually drift into the eastern Great Lakes
through Sunday. Weak low pressure will slowly lift into the
Great Lakes Monday and Tuesday, pulling a cold front across the
region. High pressure will attempt to return Wednesday.

&&

.NEAR TERM /THROUGH SATURDAY NIGHT/...

9:37 PM EDT Update...

Forecast remains valid per latest trends in obs and model
guidance. Please see discussion below for further details.

Previous Discussion...

Little change expected to the weather map through Saturday night as
strong Canadian high pressure at the surface remains in firm
control, drifting slowly from the central Great Lakes this afternoon
into the eastern Great Lakes by Saturday night. This will keep
mostly clear and comfortable conditions in place as low-level
northeasterly flow keeps dew points in the 50s. Another night of
clear skies, light winds, and the dry airmass will lead to lows in
the mid/upper 50s tonight, with some upper 40s to low 50s possible
in sheltered valleys of interior NE Ohio and NW PA. Rising mid-level
heights Saturday as the mid/upper trough axis over the NE CONUS
slides a bit farther east allowing the ridge over the Midwest to
fold east into the Great Lakes will support warmer highs in the
low/mid 80s, but as mentioned, dew points will remain comfortable.
Slightly warmer Saturday night as warm air advection and high clouds
increase in response to developing return flow, so expect lows to
stay in the low 60s in most areas, with upper 50s in interior NW
PA.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
An omega upper level blocking pattern will stick around for much of
Sunday with high pressure remaining the primary influence. This will
allow for dry conditions on Sunday, although with a southerly flow
becoming established, expect temperatures to be the warmest this
forecast period with highs climbing into the upper 80s to low 90s.
The shift in weather patterns will begin on Sunday night as the
aforementioned blocking pattern begins to break down with a trough
over the central US merging with a trough over the East Coast. This
trough feature will persist over the region through the end of this
period, moving multiple areas of enhanced upper level energy along
it and providing support for showers and thunderstorms on Monday.

The extent of showers and thunderstorms is highly dependent on the
timing of the various features moving into the area and how they
interact with one another. With increased moisture and WAA,
afternoon instability on Monday will climb to 1000-1500 J/kg,
although some models suggest even higher instability values across
the western counties. Given this enhanced surface lift, opted to
maintain the highest chance of PoPs from late Monday morning through
Monday evening, taping to just a slight chance through the overnight
hours. The biggest thing missing on the day on Monday would be any
suitable upper level support. Will have to continue to monitor this
setup , especially if there is a shortwave that develops and moves
across the area Monday afternoon which would act to enhance the
storm potential. Highs on Monday will be in the mid to upper 80s,
although in areas that receive precipitation expect a bit cooler of
temperatures. Overnight lows through the period will drop into the
mid to upper 60s.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
The overall synoptic pattern looks to become more favorable for
widespread showers and thunderstorms by Tuesday as an upper level
trough and surface low influence the area. On Tuesday, a warm front
is expected to lift north of the area, increasing both moisture and
temperatures behind it. Daytime instability across the area should
again climb to 1500 J/kg or more, especially across western
counties, providing sufficient surface support. Aloft, a vort max
looks to progress east across the area providing support aloft. The
storm chances will continue through the overnight hours and into
Wednesday as a cold front approaches from the east. This boundary is
expected to stall across the CWA through Friday, ultimately keeping
the chances of showers and thunderstorms over the area for much of
the week. If this boundary shifts north or south any, the location
and support for showers and thunderstorms will also shift and may
decrease precipitation chances. The main feature that will need to
be watched synoptically speaking will be the dominant ridge over the
western US and how that will influence local weather. For now, opted
to include likely PoPs Tuesday and Tuesday night, but after that
opted to cap it at slight chance given the uncertainty and model
divergence.

High temperatures through the period will be in the mid to upper 80s
with heat indices climbing into the 90s most days. Overnight lows
will linger in the mid to upper 60s.

&&

.AVIATION /00Z Saturday THROUGH Wednesday/...
VFR expected through 00Z/Sun as a ridge aloft builds from the
Upper Midwest and the surface portion of the ridge remains
anchored over/near the eastern Great Lakes, including northern
OH and NW PA. Our regional surface winds are expected to be
variable in direction around 5 to 10 knots. However, a land
breeze is expected to form over and within several miles of Lake
Erie between ~07Z and ~13Z/Sat. In addition, a lake breeze is
expected to form over and within several miles of the lake
between ~15Z/Sat and ~00Z/Sun. KCLE and KERI will be impacted by
these land and lake breezes.

Outlook...Periodic and isolated to scattered showers and
thunderstorms with non-VFR are possible Sunday night through
Wednesday.

&&

.MARINE...
High pressure over the eastern US will keep marine conditions
pleasant through the weekend. On Saturday, a northeast flow may
locally become gustier across the central basin with winds 10-15
knots and waves 1-3 feet, but still not expecting any headlines at
this time. This aforementioned high will drift off the East Coast on
Sunday, allowing for a south-southwest flow of 5-10 knots to become
established across Lake Erie through Tuesday night. Late Tuesday, a
cold front will begin to slide southeast across the lake before
settling across northern Ohio and a stalled boundary for much of
this week. This will maintain variable winds at 5-10 knots. In
addition, chances of showers and thunderstorms throughout the week
starting on Monday may result in locally higher winds and waves.

&&

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

&&

$$

SYNOPSIS...Garuckas
NEAR TERM...Garuckas/Jaszka
SHORT TERM...Campbell
LONG TERM...Campbell
AVIATION...Jaszka
MARINE...Campbell

NWS CLE Office Area Forecast Discussion