756
FXUS61 KCLE 251926
AFDCLE

Area Forecast Discussion
National Weather Service Cleveland OH
326 PM EDT Wed Sep 25 2024

.SYNOPSIS...
A weak cold front continues to meander across the area this
afternoon and will depart to the east by Thursday morning. High
pressure will build over the area for Thursday before the remnant
low pressure of Helene enters the Ohio Valley on Friday which will
persist through the weekend.

&&

.NEAR TERM /THROUGH THURSDAY NIGHT/...
A weak cold front continues to traverse the area this afternoon,
producing a line of showers from Ashtabula County southwest to
Holmes/Knox Counties. This line has developed along a moisture
convergence boundary with MUCAPE values generally 1000 J/kg or less
and bulk shear values 20-30 knots. This has allowed for a few
rumbles of thunder, but overall should limit the potential for
anything to become organized and severe. These showers will continue
to slowly diminish from west to east into tonight before the cold
front finally pushes east Thursday morning.

As high pressure builds behind the front tonight, there is a
potential for fog development along and east of I71, especially in
areas that saw precipitation today. Winds will weaken to light and
variable overnight, although the clouds may act to reduce cooling
and limit the true extent of fog. Will definitely have to continue
to monitor the potential into the overnight hours as any fog that
does develop will have the potential to impact the morning commute.

By Thursday morning, high pressure will establish itself over the
area and allow for conditions to dry out. Unfortunately, increased
moisture will continue to advect across the area as remnants of
Helene move north towards the Ohio River Valley which will keep
mostly cloudy skies across the area through Thursday night. High
temperatures on Thursday will remain mild in the low to mid 70s.
Overnight lows will drop into the upper 50s to low 60s.

&&

.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
The upper level trough is expected to evolve into a closed low over
the Mid Mississippi Valley on Thursday. In addition, the remnants of
Helene and the associated deep circulation will drift inland and
possibly be absorbed into an upper low on Friday and over the
weekend. A moisture axis associated the remnant of Helene will
rotate north across northern Ohio and western Pennsylvania on
Friday. The remnant low and the upper level may become vertically
stacked over the Mid Mississippi and SW Ohio Valley over the
weekend. First surge of moisture will yield an increase in
precipitable water from 1.6 to 1.9 inches Friday afternoon, a
pulling back down 1.2 to 1.5 on Saturday, and then an increase back
up to 1.6 to 1.7 inches on Sunday. Will not try to parse out
coverage of rain in this package. We would not be surprised to see
an increase in rain chances on Friday in later forecast packages.
All in all, rain chances are possible of Friday and Saturday
including overnight. However, precip coverage will probably be
higher during peak diurnal heating.

The pressure gradient will tighten considerably Friday between the
high to the northeast and low southwest. This feature will yield in
breezy northeast winds to 25 to 30 mph downwind from Lake Erie.

Highs will generally be in the 70s Friday and Saturday and a few
spots may touch 80 degrees across central Ohio on Saturday. Ample
moisture in air will hamper temps from fluctuating and lows will
remain around 60s.

&&

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
The upper low will finally begin lift east across the Ohio Valley to
the Mid Atlantic by Monday. There`s still some uncertainty in how
quickly the low exits and whether or not a ridge builds over the
region so maintained rain chances Sunday through early Tuesday. A
new sharp trough will track across the northern tier of the Plains
Monday into Tuesday. The associated trough axis is expected to sweep
across the Great Lakes on Tuesday and finally scour the remaining
moisture. An associated cold front is expected to sweep through the
area on Tuesday. This feature will yield the coolest night of the
forecast with Wednesday morning lows in the 40s.

&&

.AVIATION /18Z Wednesday THROUGH Monday/...
Quiet a mix bag of conditions across the area this afternoon as
a cold front slowly meanders east. Behind the boundary/west of
I71, ceilings continue to bounce between high end MVFR/low end
VFR with winds from the west-northwest at 5-10 knots. These
conditions will likely continue over the next couple hours. By
evening, most western terminals, including KTOL, KFDY, and KMFD
should rebound to VFR through the first half of tonight. For
areas along and east of I71, conditions continue to range from
IFR to VFR due to a variety of reasons. First off, there are
generally lower ceilings ahead of the cold front, generally
ranging from 800-1500 ft, but with some scattering in the cloud
deck. The second reason is due to ongoing precipitation just
ahead of the boundary extending from eastern Cuyahoga County,
southwest to Knox County. Terminals that are impacted by this
line will likely have visibilities reduced to MVFR/IFR
visibilities. In addition, winds will persist from the southwest
at 5-10 knots through this evening. In general, this group of
terminals are not likely to rebound to VFR until tomorrow.

By tonight, winds will become light and variable across the
area. For far western terminals, conditions should remain VFR.
Elsewhere, especially in areas where it rains today, there is a
potential for fog develop that will reduce conditions to MVFR
and IFR in spots. The highest confidence in conditions being
reduced to IFR visibilities is at KCAK and KYNG where
visibilities could drop below 2SM with ceilings lowering below
1kft. KCLE, KMFD, and KERI may see some patchy fog, but with
lower confidence opted to only drop them to MVFR with this
update. By the end of this period, winds will begin to increase
to 5-10 knots from the northeast.

Outlook...Strong northeast winds are expected across the region
on Friday. Non-VFR may return in showers and thunderstorms this
weekend.

&&

.MARINE...
A cold front will finally push through Lake Erie overnight. Winds
will become westerly this evening and northwest to north 5 to 10
knots by Thursday morning. Winds will continue to veer to the
northeast by midday Thursday as high pressure builds over Lake Erie.
In addition, winds will strengthen to 10 to 20 knots as the remnants
of Helene move inland on Thursday night. Winds may peak at 20 to 25
knots Friday afternoon into Friday evening. Can not rule out winds
reaching as high as 30 knots. Therefore Small Craft Advisories are
likely for Friday morning through late Friday night or Saturday
morning. Northeast winds diminish to to 10 to 15 knots with winds
near 20 knots likely in the open waters of the central basin. It
will probably remain choppy through Saturday. East/northeast winds
10 to 15 knots will persist through Sunday and finally collapsing on
Monday with easterly winds 10 knots or less.

&&

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

&&

$$

SYNOPSIS...Campbell
NEAR TERM...Campbell
SHORT TERM...FZ
LONG TERM...FZ
AVIATION...Campbell
MARINE...FZ