000
FXUS61 KCLE 211321
AFDCLE

Area Forecast Discussion
National Weather Service Cleveland OH
921 AM EDT Sun Apr 21 2024

.SYNOPSIS...
High pressure remains in control of the weather through Monday
night. A low pressure tracks through the Great Lakes on Tuesday,
lifting a warm front across the area Tuesday morning followed by
a cold front Tuesday night. Troughing lingers behind this system
on Wednesday before high pressure returns on Thursday.

&&

.NEAR TERM /THROUGH MONDAY/...
930 AM Update...
Minor adjustments were made to temperatures, but with cloud
cover lingering across the area this morning, there were no real
changes needed with this update.

Previous Discussion...
Generally quiet weather for the near term. A vort max and
subtle surface trough axis will move through this morning. Can`t
entirely rule out the combination of these features picking up
a sprinkle or flurry off of Lake Erie into far Northeast OH or
Northwest PA this morning (as confirmed by a few extremely light
radar returns east of Cleveland), though a dry airmass should
preclude any measurable precip so no POPs for it. Otherwise,
another subtle low to mid- level trough axis moves through early
this afternoon. It has remained mostly cloudy overnight and
will remain mostly cloudy for most of today as these features
move through. Confluence aloft behind the trough axis as it
departs into this evening should allow for a clearing trend from
northwest to southeast, with the loss of heating near sunset
further aiding in clearing skies into tonight. The eastern
lakeshore should also begin clearing a bit sooner this afternoon
as a lake shadow develops. Expect partly to mostly clear
conditions to then persist tonight and Monday, though likely
with enough low level moisture for a decent cumulus field to
develop Monday afternoon.

Highs today will rebound a bit from Saturday, ranging from the
upper 40s to near 50 in far Northeast OH and Northwest PA to the
mid to upper 50s along the I-75 corridor. Lows tonight will
generally range from the low to mid 30s inland to the upper 30s
to near 40 along the immediate lakeshore. We will see a more
traditional radiational cooling setup tonight so expect some
variance, with rural areas and more sheltered / lower spots
cooling more (some typical cold spots likely getting below
freezing) while urban areas and those on hilltops cool a bit
less. Highs on Monday will range from the mid to upper 50s in
Northwest PA to the low to mid 60s in Ohio. Winds will be fairly
tranquil this period, with some gusts to 20-25 MPH possible
this afternoon in Northwest OH and near the lakeshore farther
east. Gusts Monday afternoon may reach 20 MPH in Northwest OH.

More expansive cloud cover than expected kept temperatures a
few degrees warmer than forecasted overnight into this morning
and significantly limited frost potential. Canceled the
remaining portions of the Frost Advisory for this morning
shortly after 6 AM. It`s possible a few areas got some frost
where skies briefly cleared and temperatures dropped to 33-35
degrees, from portions of Lucas/Ottawa east-southeast to
portions of Medina/Summit, along with interior Northwest PA east
of I-79...though overall, the clouds "spoiled" the frost setup.
A much more traditional radiational cooling / frost setup for
tonight into Monday morning, assuming we actually manage to
clear the clouds (we should have a better chance with large
scale subsidence behind the departing shortwave). Winds will be
light and should decouple across most of the area, save for
perhaps a few hill tops and near the lake. We will need a frost
headline for most of the forecast area for tonight into Monday
morning and may need to think about targeted freeze warnings
for the typically colder spots (parts of interior northern Ohio,
such as near Wooster, along with interior Northwest PA). While
we were able to get this morning`s headline completely off the
board, some neighboring WFOs still have frost/freeze products
active for this morning. To give day shift a better chance to
collaborate where new headlines are needed, the timing of said
headlines, and if any areas need a Freeze Warning vs just a
Frost Advisory, will not raise tonight`s headlines yet.

&&

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
Cloud cover will be on the increase Monday night into Tuesday ahead
of an upper level trough sliding southeast into the Great Lakes
Region. South to southwest winds will be breezy on Tuesday,
advecting a warmer airmass north into the area. Dewpoints will start
the day in the 30s on Tuesday and take some time to moisten. Little
to no instability is forecast on Tuesday in the warm sector given an
extensive mid cloud deck and low boundary layer moisture but rain is
forecast to spread west to east across the area Tuesday afternoon
and night. The cold front trails as the surface low tracks well
northeast into Quebec, pushing south of Lake Erie after midnight
Tuesday night. Will carry a chance of thunderstorms with the front
although instability will still be limited. Highs on Tuesday will be
in the lower 60s area wide, dropping back into the upper 40s to
lower 50s for highs behind the front on Wednesday.

High pressure builds in quickly behind the front on Wednesday night.
It looks like cloud cover should clear, allowing areas of frost to
form Wednesday night. It is also possible that much of the area
could see sub-freezing conditions.

&&

.LONG TERM /THURSDAY THROUGH SATURDAY/...
High pressure with nearly full sun overhead on Thursday should
contribute to temperatures warming about 5 degrees, except near Lake
Erie. High pressure shifts to New England on Friday as upper level
ridging builds overhead. Temperatures will trend warmer through the
extended, especially behind a warm front that will lift north Friday
night. It is possible that we could see chances of showers and
thunderstorms as early as Friday afternoon but better chances will
be through Saturday as a shortwave rounds the ridge aloft, kicking
off activity. Temperatures will be above normal (65-75F) again by
Saturday.

&&

.AVIATION /12Z Sunday THROUGH Thursday/...
VFR ongoing and is expected to persist through the TAF period.
A broken to overcast deck in the 4-5k foot range will persist
this morning into this afternoon. By mid to late afternoon
these ceilings should scatter out with mainly clear skies
persisting tonight. Localized valley fog is possible late
tonight, but with a dry airmass it should be localized and
confidence is not currently high enough to include in any TAFs.

West-northwest winds are expected to increase to around 10
knots later this morning through this afternoon. Periodic gusts
up to 20 knots are possible at CLE/ERI. Winds will become light
and variable quickly after sunset this evening.

Outlook...Non-VFR possible in showers Tuesday. Non-VFR may
persist into early Wednesday.

&&

.MARINE...
Winds back to southwesterly today but remain elevated east of
Cleveland at 15-20 knots. Waves of 3 to 5 feet can be expected in
the open waters. A ridge expands east over Lake Erie on Monday with
light winds and waves. South to southwest winds will increase to 15-
25 knots on Tuesday as low pressure moves east across the Upper
Great Lakes. A trailing cold front will move southeast across Lake
Erie Tuesday night with a wind shift to the northwest and post
frontal winds of 15 to 20 knots. It is unclear if a Small Craft
Advisory will be needed with the offshore flow on Tuesday but will
likely be needed east of Vermilion as flow becomes onshore and waves
build on Wednesday.

High pressure will build east across the Great Lakes Region
Wednesday night through Thursday night. A warm front will lift north
across the lake Friday night with southerly winds increasing behind
it.

&&

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

&&

$$

SYNOPSIS...Sullivan
NEAR TERM...Campbell/Sullivan
SHORT TERM...KEC
LONG TERM...KEC
AVIATION...Sullivan
MARINE...KEC