713
FXUS61 KCLE 310916
AFDCLE

Area Forecast Discussion
National Weather Service Cleveland OH
416 AM EST Fri Jan 31 2025

.SYNOPSIS...
Low pressure moves northeast across the area today, followed by
a cold front tonight. High pressure builds from the northwest
on Saturday before it departs to the east on Sunday. A cold
front will cross the region on Monday.

&&

.NEAR TERM /THROUGH SATURDAY/...
First wave of rain has moved northeast to generally along and
east of I-77. Fairly soupy conditions develop in its wake with
low stratus and hazy conditions, with patchy dense fog also
possible. Rain should fill back in areawide by late this morning
through much of the early afternoon hours. A few models have a
little elevated instability (about 100-300 J/kg of MUCAPE), so
would not be entirely shocked if somebody heard a rumble of
thunder, though did not put in the forecast. At a minimum,
could see showers yield convective characteristics this
afternoon, especially along and ahead of the cold front towards
the southern part of the forecast area this afternoon. The
actual surface low makes its way northeastward across the
forecast area this afternoon, with rain scattering out in its
wake due to a dry slot.

In total, should see about a half inch of QPF. Snowmelt and and
rain amounts may lead to minor river rises and minor nuisance
flooding, mainly in the snowbelt region of Northeast Ohio and
Northwest Pennsylvania. There remains some low potential for
ice breakup on area rivers, leading to ice jam flooding today
into the weekend in a few of the typical problem spots. Recent
reports from spotters indicate that river ice is weakened and
thin, which should reduce the overall ice jam risk.

The deformation zone located to the northwest of the low track
will slide southeastward as the low departs tonight, which
should initially manifest as a pretty good area of rain. Strong
cold air advection will eventually transition precipitation to
snow between 00-05Z. Most models have good moisture and lift in
the dendritic growth zone, so could see a brief period of large
dendritic snow falling with snow rates potentially even up to
1"/hr for about an hour or so before it rapidly dissipating as
dry air moves in from the northwest. Marginal ambient
surface/air temperatures and extremely short duration will limit
overall snow accumulations to less than an inch for most area.

It`s possible there could be a very short period (on the order
of a couple hours) where loss of moisture aloft results in
patchy freezing drizzle before the low-levels completely dry
out. For now, didn`t put it in the forecast but it`ll be
something to watch for.

Temperatures actually cool down a fair amount tonight with lows
down into the 20s and even the teens for parts of the snowbelt
region in Northeast Ohio and Northwest Pennsylvania. High
pressure centered over the northern Great Lakes region extends a
ridge of high pressure over our forecast area by Saturday, so
should see mostly sunny skies on Saturday for much of the area,
though temperatures will remain cool.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY NIGHT/...
The short term period will begin with a weak clipper system moving
southeast through the Great Lakes Saturday night into Sunday,
bringing a glancing blow of rain and/or snow across the area,
primarily on Sunday. Strong warm air advection is expected on the
southern side of this system, pushing temperatures into the mid to
upper 40s by Sunday afternoon. Little to no snow accumulation is
expected.

The Sunday clipper system will eventually drag a cold front south
through the area on Monday as surface high pressure builds across
the Great Lakes. Not anticipating anything too significant with the
frontal passage given the building high, but can`t rule out a few
light rain and/or snow showers across Northeast Ohio and Northwest
Pennsylvania Monday and Monday night.

&&

.LONG TERM /TUESDAY THROUGH THURSDAY/...
A more active weather pattern will develop for the long term period,
with above-average temperatures becoming increasingly likely by
Wednesday and especially for Thursday.

A large upper-level ridge will begin to build across the western
CONUS on Tuesday, shifting east towards the central CONUS by
Wednesday, and eventually reaching the eastern CONUS by Thursday. An
upper-level trough will replace the exiting ridge across the western
CONUS and phase with the sub-tropical jet, eliciting a surface
cyclogenesis response across the Central Plains on Wednesday, with
the system reaching the Great Lakes and lifting a warm front north
through the area Wednesday night into Thursday. Large uncertainty
exists with this system, particularly concerning temperatures and
dew points. Ensemble histograms reveal a bimodal distribution of
temperatures/dew points on Thursday, with the NBM deterministic
falling at the local minimum of the spectrum. Given the upper-level
pattern and anticipated strong warm air advection, opted to go with
the higher end of temperature guidance (closer to 75th percentile
NBM in this case), yielding upper 50s to lower 60s across the area
on Thursday. Ensemble probabilities remain low, but nonzero, for the
potential of strong storms within a low CAPE, high shear environment
Thursday afternoon. Will need to continue monitoring model trends
over the next several days.

Otherwise, much of the area is expected to see widespread rain
associated with isentropic ascent ahead of the developing low
pressure system, beginning Wednesday, with the potential
for rain continuing through Thursday.

&&

.AVIATION /06Z Friday THROUGH Tuesday/...
Rain showers continue to overspread across the area, with
ceilings and visibilities gradually deteriorating shortly after
that. Already starting to see evidence of that in the southwest
part of the forecast area with ceilings below 1000 ft at KTOL
and KFDY, with ceilings down to 200 ft upstream in other parts
of Ohio and Indiana. The expectation is that the entire forecast
area should have ceilings of 500 ft or less with visibilities of
2SM or less by 12Z this morning with these conditions continuing
through at least Friday evening. At times, may see ceilings as
low as 200 ft and visibilities as low as 1/2 SM.

The cold front located to the north swings through after 00Z,
with a transition to snow between 00-05Z from north to south.
This transition may occur with moderate precipitation going on,
so there is a good chance there may be 1-2 hours of moderate to
heavy snowfall with large dendritic flakes falling, though
heaviest snow will be occurring with mild temperatures and thus
limited impacts from accumulations. Visibilities of 1SM are
expected, as low as 1/2SM may briefly be possible. Snow
shouldn`t last very long and should quickly as as dry air moves
in from the northwest. May start to see improving conditions
right around 06Z and definitely thereafter, via improving
ceilings/visibilities and decreasing cloud cover.

Outlook...Non-VFR is possible with isolated to scattered
rain/snow for Northeast Ohio and Northwest Pennsylvania Sunday
through Monday.

&&

.MARINE...
Given that Small Craft Advisory issuance remains suspended until
further notice due to extensive ice cover, the marine period overall
appears fairly quiet.

Winds will briefly shift towards the north behind a cold front later
this evening and overnight, near 20 knots. Winds will gradually
decrease to around 10 knots, shifting towards the east by Saturday
night. Winds pick up out of the southeast, then south on Sunday into
Monday, shifting towards the northwest behind a cold front Monday
afternoon, 10 to 15 knots. Winds will then favor a northerly
direction, around 10 knots, through Tuesday.

&&

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

&&

$$

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