-- Discussion containing changed information from previous version are highlighted. --
041
FXUS61 KCLE 241108
AFDCLE

Area Forecast Discussion
National Weather Service Cleveland OH
708 AM EDT Fri May 24 2024

.SYNOPSIS...
A warm front will lift north across the area later today through
tonight as low pressure tracks into the Upper Great Lakes. The
associated cold front will sweep east across the area on Saturday.
High pressure will return for Saturday night but will be followed by
another low pressure system tracking from the Plains to the Great
Lakes Sunday night through Monday.

&&

.NEAR TERM /THROUGH SATURDAY/...
-- Changed Discussion --
Forecast remains on track for today. We will be keeping an eye
on the mature MCS tracking across Iowa and evolution today.
Movement should be to the northeast with ridging ahead of it.
Remnant energy from this feature will approach NW Ohio this
evening and may need to make adjustments to the forecast to
account for this.

Previous discussion...
Shortwave energy will depart to the east this morning with a ridge
building overhead today and mostly sunny skies for the daytime
hours. A noticeable dewpoint gradient will remain in place with
values dipping into the 40s across the north while closer to 60
degrees towards Central Ohio. A few high resolution models try
to develop a few showers in the southeastern counties but model
sounding show a strong capping inversion so kept the forecast
dry. Inland areas will see southerly winds while lake breezes
will develop this afternoon and reinforce this moisture
gradient. A warm front will lift north but will take until
closer to this evening to make much progress. With that in mind,
did nudge forecast highs up a degrees or two across Northwest
and North Central Ohio.

An upper level trough over the northern Plains this morning will
become negatively tilted as it curls into the Upper Midwest tonight.
At the surface, low pressure will track north into Manitoba while an
occluded front extends southeast across Michigan and a trailing
cold front approaches from the west. Theta-e advection
increases through the evening and could see scattered showers
reach Northwest Ohio but the better forcing fueled by a low
level jet is focused north of the area towards Lake Huron.
Expect to see better coverage of showers pass north of the area
but do gradually expand pops from west to east overnight as the
warm front lifts north and we end up in the warm sector.
Coverage of showers is expected to be pretty low through
Saturday morning until the atmosphere has a chance to
destabilize with coverage increasing during the afternoon along
and ahead of the eastward moving cold front. ML CAPE values are
forecast to reach 1500-2000 J/kg generally east of Interstate
71. Activity may fire closer to the lake initially where
surface convergence will be stronger then expand to the south
and east. Given the limited coverage during the morning most
areas should still see highs near 80 degrees but humidity will
also be up as dewpoints reach 60-65 degrees. The entire area has
been placed in a marginal risk of severe weather with 20-30
knots of 0-6km shear. The primary hazards will be a few wind
gusts of 50-60 mph and hail of penny to quarter size.
-- End Changed Discussion --

&&

.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY NIGHT/...
A cold front departing the area Saturday evening will allow for high
pressure to briefly push south over the area and allow for a break
in precipitation before the active pattern continues for the
remainder of the period. On Sunday, a deepening low pressure system
over the Plains associated with an amplifying shortwave will push
northeast across the western Great Lakes region, moving a warm front
north on Sunday followed by a cold front on Monday. Between the
strong upper level support and frontogenesis, confidence is high in
widespread showers and thunderstorms Sunday afternoon through Monday
evening. On Sunday, the area will remain in the warm sector of the
low, allowing for ample moisture to advect across the CWA and CAPE
values to climb to 1000-2000 J/kg with the most instability expected
across the western and southwestern counties. During the late
afternoon/evening hours on Sunday, a LLJ of 50-60 knots will push
across the same areas, only aiding in the development of convection.
Some thunderstorms may become strong to severe with strong winds,
large hail, and very heavy rainfall the primary concerns. Current
guidance suggests PWAT values of 1.5-1.7 inches with an increasing
warm cloud layer into Sunday evening/overnight. With these
conditions, except the strongest storms to produce very efficient
rainfall and possibly cause local nuisance flooding and local rises
on rivers. There remains quite a bit of uncertainty in the full
severe weather threat on Sunday into Monday, especially in regards
to how fast the aforementioned warm front pushes north which will be
critical in all other ingredients coming together. The SPC Day 3
Outlook has placed the west and southwestern counties in a Marginal
Risk for Severe weather, which continues to reflect the current
thinking of the areas in the CWA with the greatest potential for
severe weather. In addition, to highlight the heavy rain potential,
WPC has issued a Day 3 ERO slight risk across the southern counties
with a marginal risk elsewhere. By Monday night, showers should
taper briefly over the area as the cold front departs east, but the
period of dry weather will be short lived as a secondary cold front
begins to impact the area lake Monday night into the start of
Tuesday.

Overnight lows on Saturday will drop into the mid to upper 50s
across the area, but with a warm front lifting north on Sunday night
expect lows to be a bit more mild and only drop into the mid 60s
Sunday night. Monday night will again cool to the mid 50s behind the
departing cold front. High temperatures will follow a similar trend
with highs on Sunday climbing into the low 80s, but remaining a bit
cooler on Monday with temperatures only climbing into the mid to
upper 70s.

&&

.LONG TERM /TUESDAY THROUGH THURSDAY/...
An active weather pattern is forecast to continue through much of
the long term period as an upper level trough continues to pivot
over the eastern CONUS, sending numerous shortwaves along it that
have the potential to help support showers and thunderstorms across
the area. Initially on Tuesday, the shower potential will be
enhanced as a secondary cold front associated with a low near
northern Ontario/Quebec. With the active pattern and lingering
trough, opted to include chance PoPs through Wednesday before high
pressure begins to push east across the area and allow conditions to
dry out for the end of the period. There is a bit of model
divergence in the timing of this high pressure and the arrival of
the drier airmass, but there is an overall general consensus amongst
long range models that a high will be in place by Thursday.

With a progressively cooler, west-northwest flow expected, highs
through the period will be near normal climbing into the upper 60s
to low 70s. Overnight lows will be in the upper 40s to low 50s.

&&

.AVIATION /12Z Friday THROUGH Tuesday/...
Primarily mid and high cloud overhead at TAF issuance is
expected to depart to the east through 12Z. As this cloud
clears, some reduced visibilities are possible for a brief
window just before sunrise. Included a couple hour tempo for
MVFR visibilities at MFD/CAK but confidence is only medium in
this occurrence. Skies will be mostly sunny through the daytime
hours with clouds arriving from west to east tonight as moisture
arrives along a pre-frontal trough. It is possible that
scattered showers or even a few thunderstorms could reach
TOL/FDY/CLE before the end of the TAF window but confidence was
not enough to include prevailing conditions.

Winds are generally light and variable through 15Z then out of
the south/southwest. CLE/ERI are expected to have a lake breeze
develop between 15-18Z. A drainage wind returns by 02Z tonight
with southeasterly winds.

Outlook...Scattered showers and storms possible Saturday
afternoon and evening. Chance of thunderstorms returns Sunday
night into Monday with non-VFR possible. Lower chances of
showers and thunderstorms linger into Tuesday.

&&

.MARINE...
Winds today will vary in direction but remain between 5-10 knots as
a low pressure system over the northern Plains meanders north into
Canada. Tonight, winds will become south-southeasterly as a warm
front lifts north of the area and increase to 10-15 knots. An
associated cold front will move east Saturday afternoon into the
evening, allowing winds to shift to become west-northwesterly at 5-
10 knots into Sunday. A very similar progression of another low over
the Plains will occur on Sunday into Monday as a warm front lifts
north of the lake on Sunday, increasing southerly winds to 10-15
knots. The most notable winds of this forecast period will occur on
Monday afternoon as the associated cold front moves east across the
area, shifting winds to gain a more westerly component and
increasing them to 15-20 knots. On Monday evening into the
overnight, winds across the central and eastern basin may briefly
increase to 20-25 knots and will be the period to monitor for any
marine headlines. Boaters should continue to monitor the forecast,
especially given that Monday is a holiday and increased boating is
possible. In addition, with warming Lake Erie temperatures, beach
goers for the holiday should be aware of the potential for rip
currents and stay up to date with the forecast. A secondary cold
front is expected to move southeast across the area on Tuesday into
Wednesday, allowing winds to become 10-15 knots from the northwest
before high pressure builds in on Thursday and winds becomes 5-10
knots.

&&

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

&&

$$

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