Area Forecast Discussion
Issued by NWS Cleveland, OH

Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS61 KCLE 161336
AFDCLE

Area Forecast Discussion
National Weather Service Cleveland OH
936 AM EDT Sat Mar 16 2024

.SYNOPSIS...
A ridge exits gradually eastward before a cold front sweeps
eastward through our region this evening through the wee hours of
Sunday morning. Behind the front, a trough lingers over northern
Ohio and northwest Pennsylvania through the rest of this weekend.
On Monday, a ridge should begin to build from the north-central
United States.

&&

.NEAR TERM /THROUGH SUNDAY/...
930 AM EDT Update...

Fog is beginning to diminish as diurnal mixing increases.
Visibility will improve over the next couple of hours. Outside
of making minor adjustments to hourly temperatures and dew
points for the next several hours, no changes were needed with
this update.

Previous Discussion...

W`erly flow aloft persists over our region through Sunday as a
mid/upper-level low wobbles from northern ON to southwestern
QC. Simultaneously, multiple shortwave disturbances revolve
around the low and traverse our region. At the surface, a ridge
exits gradually E`ward before a cold front sweeps generally
E`ward through northern OH and NW PA this evening through the
wee hours of Sunday morning. Behind the front, a trough lingers
over the Great Lakes and vicinity, including our CWA. Lingering
low-level clouds, some of which have expanded downward via
nocturnal cooling to form patchy fog, and patchy river valley
steam fog early this morning should dissipate by late morning
as diurnal convective mixing of the boundary layer commences
shortly after sunrise and taps into drier air aloft at/near
3kft-5kft MSL. Otherwise, expect periodic and mainly mid/upper-
level cloudiness to impact our region in association with moist
isentropic ascent aloft preceding the shortwave trough axes.

As the surface ridge exits generally E`ward today, SW`erly
surface winds develop and will be associated with low-level WAA
ahead of the aforementioned cold front. These SW`erly surface
winds are expected to gust up to 30-40 mph late this morning
through early evening as diurnal convective mixing of the
boundary layer taps into stronger flow aloft. Recent runs of
HREF indicate the probabilities of advisory-criteria surface
gusts of at least 46 mph remain less than 20% in our CWA. The
low-level WAA combined with daytime heating amidst intervals of
sunshine are forecast to allow late afternoon highs to reach the
mid 50`s to near 60F in NW PA and mainly the upper 50`s to
lower 60`s in northern OH. Rain showers associated with the
aforementioned cold front are expected to impact our region for
several hours at any one location this evening through the wee
hours of Sunday morning via low-level convergence and associated
moist ascent along the front. Low-level CAA behind the front
will contribute to lows reaching the mid to upper 30`s around
daybreak Sunday. As low-level moisture remains sufficient and
850 mb temps cool to near -7C over ~6C Lake Erie, lake-effect
rain/wet snow showers are expected to occur over and generally
east of Lake Erie, in/near the primary snowbelt of NE OH/NW PA,
amidst W`erly mean low-level flow overnight tonight. Any snow
accumulations are expected to be a trace by daybreak.

Abundant cloud cover, including lake-effect stratocumuli, and
continued low-level CAA behind the cold front will result in a
much colder day on Sunday. Afternoon highs are expected to reach
the upper 30`s to lower 40`s in NW PA and the lower to mid 40`s
in northern OH. Scattered lake-effect rain/wet snow showers
should continue to impact the primary snowbelt and vicinity as
the thermodynamic/kinematic environment changes little compared
to that described in the above paragraph. A stout capping
inversion accompanying the low-level cold air mass should allow
lake-induced EL`s to remain around 5kft to 8kft above lake-
level and promote light to steady lake-effect precip at most.
Outside the lake-effect precip, isolated rain/wet snow showers
are possible as weak potential instability in the lowest 1 km
AGL is released via low-level convergence/attendant moist ascent
along surface trough axes accompanying the shortwave disturbances
aloft. Any wet snow accumulations are expected to be less than
one inch and mainly confined to the higher terrain in NW PA.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
The short term forecast period will be appropriate for the final
days of astronomical winter with cooler temperatures and persistent
chances of snow through Tuesday night. An upper trough will nestle
in across the eastern CONUS late in the weekend and support a
general surface trough. A reinforcing cold front will push through
the region on Monday with the upper trough axis and bring the best
chances of snow across the entire forecast area. Otherwise,
scattered snow showers will be favored through much of the period
with the general trough pattern. Lake enhancement will be possible
with snow showers and allow for the highest snow chances and likely
highest snowfall accumulations to be across Northeast Ohio and
Northwest Pennsylvania. A couple inches of snow will be expected
through the entire period in NE OH/NW PA, which should stay below
any need for a headline. However, if some squalls persist over a
particular area, there could be a need for a marginal winter
headline.

&&

.LONG TERM /WEDNESDAY THROUGH FRIDAY/...
High pressure will start to enter the region from the northwest on
Wednesday as the main upper trough shifts eastward. Any lake
enhanced precipitation should be over to start the period with
backing winds across the region, and drier, northwest flow will
return on Wednesday to fully end any precipitation. Therefore, will
have a generally dry forecast with improving temperatures on
Wednesday and Thursday. For the end of the week, there remains
enough uncertainty with the evolution of the southern stream trough
and the next northern stream trough to have low confidence on a dry
vs. wet forecast. Therefore, have a fairly generic low chance of
rain forecast for Friday with temperatures remaining fairly
stagnant.

&&

.AVIATION /12Z Saturday THROUGH Wednesday/...
W`erly flow aloft and embedded disturbances affect our region
through 12Z/Sun. At the surface, a ridge exits generally E`ward
as a cold front approaches from the Upper MS Valley and vicinity.
This front should sweep E`ward through our region between
~00Z and ~07Z/Sun and be followed by a lingering trough through
12Z/Sun. Ahead of the front, SW`erly regional surface winds
around 5-10 knots early this morning strengthen to about 10-20
knots with gusts up to 20-30 knots, especially after ~15Z/Sat.
Behind the cold front, our regional surface winds veer to
WNW`erly and remain around 10-20 knots with gusts up to 25
knots. However, the gusts should cease toward 12Z/Sun.

Low-level clouds, pockets of fog, and associated MVFR to IFR are
lingering across portions of NE OH and NW PA early this morning.
These low clouds will continue to exit generally E`ward and
NE`ward through ~17Z/Sat via SW`erly mean low-level flow on the
backside of the departing ridge. Eventual diurnal convective
mixing of the boundary layer will allow fog to dissipate by
~14Z/Sat. Otherwise VFR are expected along and ahead of the cold
front and any one location is expected to experience several
hours of rain shower activity with the approach and subsequent
passage of the front. Behind the cold front, scattered to
widespread low clouds, associated VFR ceilings, and mainly fair
weather are expected. However, scattered lake-effect rain/wet
snow showers will stream generally E`ward from Lake Erie after
~06Z/Sun and impact the primary snowbelt of NE OH and NW PA,
including KERI.

Outlook...Non-VFR expected with periods of rain and/or snow
Sunday through Wednesday.

&&

.MARINE...
Low pressure north of Lake Superior will slide southeast today and
extend a cold front across the lake tonight. The pressure gradient
ahead of the system and cold front will increase where southwest
winds will become quite strong during the afternoon hours and waves
will respond and increase. Have issued a Small Craft Advisory for
Lake Erie west of Geneva-on-the-Lake through the first part of
tonight. The cold front will cross the lake and westerly flow will
take over and onshore flow will generate higher waves over the
eastern half of Lake Erie. This elevated onshore flow will then
continue through Sunday, Monday, and the first part of Tuesday, as a
trough settles in across the region and a reinforcing cold front on
Monday will only enhance the flow. Therefore, a new Small Craft
Advisory will eventually be needed starting late tonight but
extending well into next week - perhaps Tuesday night. Flow will
start backing to the southwest Tuesday night into Wednesday but
returning to the northwest on Wednesday afternoon, which will be the
catalyst for ending the anticipated Small Craft Advisory.

&&

.CLE WATCHES/WARNINGS/ADVISORIES...
OH...None.
PA...None.
NY...None.
MARINE...Small Craft Advisory until 10 PM EDT this evening for
     LEZ142>147.

&&

$$

SYNOPSIS...Jaszka
NEAR TERM...Jaszka/Maines
SHORT TERM...Sefcovic
LONG TERM...Sefcovic
AVIATION...Jaszka
MARINE...Sefcovic


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.