806
FXUS61 KCLE 291951
AFDCLE

Area Forecast Discussion
National Weather Service Cleveland OH
351 PM EDT Mon Apr 29 2024

.SYNOPSIS...
A cold front will move east across the area tonight into
Tuesday. High pressure will return to the area late Tuesday
through Wednesday before another low pressure system moving
through the Midwest moves a warm front north across the area
Wednesday night into Thursday. A cold front associated with this
low will move east Friday night into Saturday.

&&

.NEAR TERM /THROUGH TUESDAY NIGHT/...
Currently a low pressure system over the Upper Midwest has
extended a warm front north of the area with a cold front
extending south near the IN/IL border. This has left the entire
CWA in the warm sector of this low today, allowing for continued
WAA and moisture advection. Looking at observations,
temperatures have climbed into the upper 70s to low 80s with
dewpoints in the mid to upper 50s. These conditions have allowed
for a field of diurnal CU to become established over much of
the area. These skies will gradually transition to overcast
skies as the aforementioned cold front continues to move east
towards the area this evening and overnight. In addition,
showers and thunderstorms are currently being observed upstream
and are expected to gradually push east beginning this evening.
Overall the mesoscale environment remains marginal, but with a
nose of instability and wind shear 30-35 knots over NW OH, would
not be surprised to see some stronger thunderstorms with the
primary concern being heavy rainfall and gusty winds between
21-00Z this evening. Due to the marginal environment, SPC has
maintained a general thunder outlook across the area.

As the cold front moves east tonight, showers will become more
widespread with the chance of thunder diminishing, especially
east of I71. Overall impacts should be minimal with this system,
although scattered heavier rainfall may result in nuisance
flooding such as ponding on roadways. QPF totals for the event
are highest in west counties generally ranging from 0.5-0.7" and
are much lower in the eastern counties once the system weakens
with total rainfall only expected to be 0.2" or less.

As the cold front departs east on Tuesday, high pressure will
build in behind it and allow for dry conditions to return for
the remainder of the near term period. High temperatures on
Tuesday will be a bit milder, climbing into the low to mid 70s.
Overnight lows will only drop into the low 60s with lows Tuesday
night cooler behind the cold front as they drop into the low
50s.

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
Broad mid/upper ridging will reamplify over the central and eastern
CONUS Wednesday in response to broader mid/upper troughing
developing over the northern Rockies. This will quickly bring back
temperatures that are 10-20 degrees above normal for Wednesday and
Thursday allowing trees, shrubs, and other vegetation to continue to
leaf out at a rapid pace this week. A lead shortwave ejecting out of
the main trough will progress through the Upper Midwest and northern
Great Lakes Wednesday, with an associated surface low traversing a
warm front lifting through the central lakes. At this time, think
any convection will stay north of the region given the building
ridge and warm frontal boundary lifting quickly north, so kept
Wednesday dry. A weak cold front may sag into the area behind this
deamplifying/weakening shortwave and surface low Wednesday night,
but it should wash out in response to heights continuing to build
through Thursday, so kept Wednesday night and Thursday dry as well.
By Thursday night, the main mid/upper trough over the Rockies will
progress toward the Upper Midwest while evolving into a vertically
stacked, closed low that will extend a cold front slowly eastward.
Have slight chances for showers/storms reaching NW Ohio Thursday
night, but most precip will hold off until Friday. More on that in
the Long Term section below.

Highs will reach the mid 70s to low 80s Wednesday, with upper 70s to
low 80s Thursday. Lows Wednesday night will range from the mid to
upper 50s, with upper 50s to low 60s Thursday night.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
The aforementioned closed low over the Upper Midwest will gradually
fill and lift north across the US/Canadian border Friday through
Saturday. The deterministic GFS, ECMWF, and Canadian are still
struggling to pinpoint how far east the closed low will make it
before it drifts into Canada, but the guidance is at least in
agreement on it lifting into Canada. This will extend an initial
cold front through the area Friday night. The mid/upper ridge over
the eastern CONUS will be very amplified/sharp ahead of this front
during the day Friday. Given this strong ridge and the closed low,
it is not surprising to see that the cold front has been slowing
down, with most guidance now showing a late Friday night into
Saturday morning frontal passage. Would not be surprised to see some
additional slowing. At this time, stayed with chance PoPs in the
warm sector for showers/storms ahead of the front Friday, but with
forcing trending farther west, most may hold off until Friday night.
Have likely PoPs Friday night into Saturday as the front slowly
moves eastward. The front will be weakening due to the upper support
becoming further displaced to the NW, so not expecting widespread
severe weather (overnight timing further reduces the potential), but
a few strong storms are possible given at least weak to moderate
instability and marginal shear. This looks like a better set-up for
slow moving convection with locally heavy rainfall due to the jet
dynamics displaced to the NW leading to weak flow. PWATs will be
seasonably high, so will need to watch for areas of slow moving or
training convection Friday night into Saturday.

Periods of showers and possibly thunderstorms will continue over
eastern areas through Saturday afternoon since the cold front will
be slow to exit, so kept likely PoPs in eastern Ohio and western PA.
We`ll again need to watch for locally heavy rainfall. There should
be some drying Saturday night into Sunday, but kept chance PoPs
through the entire Saturday night through Monday period because
guidance suggests a secondary cold front around Sunday or Sunday
night/Monday as a deeper trough attempts to dig into the Great Lakes
behind the departing closed low. Lots of uncertainty on timing with
this, but it will definitely not be a washout.

Highs in the 80s Friday will cool into the mid/upper 70s Saturday
through Monday.

&&

.AVIATION /18Z Monday THROUGH Saturday/...
Widespread VFR conditions are expected to continue over the next
couple hours. Satellite imagery showers scattered to broken
diurnal CU developing across the entire area which will
gradually transition into overcast skies late this afternoon
into the evening as a cold front approaches from the east. This
cold front will result in widespread rain showers beginning near
21Z for western terminals and overnight for eastern terminals.
As these showers become more widespread, visibilities will drop
to MVFR distances with ceilings gradually diminishing to MVFR
overnight and IFR early Tuesday morning along the cold front.
Showers will begin to taper from west to east beginning Tuesday
morning with lingering showers possible into the afternoon
across the east.

In addition to the widespread showers, there is a chance for
thunderstorms especially along and west of I71 where instability
and wind shear is the greatest. Overall impact should be minimal
for most terminals with the exception of KTOL which may see an
isolated stronger thunderstorm with gusty winds up to 35 knots
and heavy rainfall. With uncertainty in the timing, opted to
not include the gust and handled the thunderstorm potential in a
tempo.

Finally looking at the wind forecast winds will remain sustained
from the southwest at 12-16 knots, gusting up to 25-30 knots
along and west of I77. There has also been a weak lake breeze
that has developed over the eastern shore of Lake Erie, shifting
winds at KERI to have a northerly component and remain weak at
5-10 knots. Near sunset, winds will weaken areawide to 5-10
knots, remaining from the southwest ahead of the front then
shifting to be west-northwesterly behind the boundary.

Outlook...Non-VFR may return in showers and thunderstorms
Thursday night into Friday.

&&

.MARINE...
A quiet week is expected on the lake as pressure gradients remain
weak. WSW winds of 5-15 knots are expected behind a weakening cold
front tonight and Tuesday, becoming SW at 5-10 knots Tuesday night
and Wednesday. Winds then go light and variable Wednesday night
until turning east at 10-15 knots Thursday and SW at 10-15 knots by
Friday. SW winds will gradually weaken to 5-10 knots Friday night
and Saturday as a weakening cold front shifts eastward.

&&

.CLIMATE...
Forecast high temperatures on Monday may be within a few degrees
of the daily record maximums for some climate locations. Here are
the historical record high temperatures for Monday, April 29th.

Date    Toledo         Mansfield      Cleveland      Akron          Youngstown     Erie
04-29   87(1899)       81(1942)       84(1899)       84(1888)       85(1942)       82(1899)

&&

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

&&

$$

SYNOPSIS...Campbell
NEAR TERM...Campbell
SHORT TERM...Garuckas
LONG TERM...Garuckas
AVIATION...Campbell
MARINE...Garuckas
CLIMATE...