206
FXUS61 KCLE 201029
AFDCLE

Area Forecast Discussion
National Weather Service Cleveland OH
629 AM EDT Mon May 20 2024

.SYNOPSIS...
A warm front will remain to the north of the area today as high
pressure departs to the east. Low pressure will track northeast
across the Plains Tuesday before pushing a cold front across the
local area Wednesday as it tracks towards James Bay. High
pressure will return for Thursday.

&&

.NEAR TERM /THROUGH TUESDAY/...
630 AM Update...

The forecast remains on track and no changes were needed with
this update. Temperatures will approach record values this
afternoon and Toledo and Mansfield have the best chance at
reaching or breaking high temp records (see climate section
below).

Previous Discussion...

A muggy, summer-like weather pattern will persist during the
near term period. There will be quite a bit of moist, unstable
air across the area today, but not much forcing to work with for
convective initiation beyond a lake breeze that will develop
this afternoon. Widely scattered showers/storms may pulse up
along this boundary this afternoon before dissipating with the
loss of diurnal heating this evening. Similar to the last few
days, steering flow will be relatively weak and there will be
very little shear so expect any showers/storms to be slow-moving
and somewhat disorganized. With that being said, thermodynamics
support a small chance of sub-severe gusty winds and small hail
in addition to locally heavy rainfall and potential for minor
flooding due to training. Dry weather will return for Monday
evening.

A shortwave will track west into the region early Tuesday
morning as low pressure begins to deepen and lift across the
Plains, which will allow PoPs to increase in western zones.
However, CAMs are still a bit inconsistent with the placement,
timing, and overall chance of precipitation so capped PoPs at
slight chance for the time being. Afternoon/evening shower and
thunderstorm chances associated with a stronger shortwave will
likely rely on whether or not showers pan out Tuesday morning
and if the atmosphere recovers/destabilizes from any convective
debris. Have slight chance to chance PoPs for now, but wouldn`t
be surprised if PoPs ended up increasing as guidance becomes
better aligned. As with typical summertime thunderstorms, there
will be enough buoyancy and moisture for (likely sub-severe)
wind gusts and small hail in addition to locally heavy rainfall.
Storms should be slightly more progressive and perhaps a bit
more widespread than previous days due to the enhanced lift from
the shortwave.

Temperatures will be well above normal to near record over the
next couple of days. Instead of highs that are typically in the
lower 70s this time of year, maximum temps will be in the mid to
upper 80s across the majority of the area today and Tuesday
with lower 90s possible west of the I-71 corridor today. It will
also feel somewhat humid with dew points in the lower 60s.
Tonight`s lows will be in the 60s with the warmest lows in the
upper 60s to around 70 degrees more likely in urban areas such
as Toledo and Cleveland.

&&

.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/...
The short term forecast period will be active to say the least. For
Tuesday night, a well organized severe episode will likely be
ongoing across the Midwest and western Great Lakes region. Some form
of this convection will continue toward the forecast area during the
nighttime hours. There is uncertainty at this time on the quality of
the convection as it approaches Northwest Ohio, as instability
factors lean toward convection becoming more elevated and less
problematic for severe potential. However, a strong low level jet
will enter the region concurrent with the convection and storms
could retain a bite to them and surface-based. Therefore, there is a
Day 2 Marginal Risk for severe weather for Northwest Ohio for a
residual strong to severe wind threat. However, due to low
confidence on storm coverage into the area, the PoP in the forecast
is relatively low.

For Wednesday, the flavor of the day appears to be typical of a
summer severe weather setup, especially with a well above normal
temperature air mass in place (80s+) with 60s dew points in the
region. An occluding low pressure system will be across Lake
Superior around daybreak on Wednesday and this system will push a
cold front toward the forecast area. Ahead of the front, the initial
air mass of the day may be disrupted by residual debris rain and
clouds from the late Tuesday night complex. If these linger too
long, they could take away somewhat from the total potential of the
environment for the day. Toward afternoon, showers and thunderstorms
will develop with the forcing of the front just west of the forecast
area and move into the region. However, the total synoptic picture
isn`t totally aligned on Wednesday afternoon as the mid-level vort
max is well displaced and just a tiny piece of the upper jet will
support the convection across the region compared to the broader jet
aloft to areas southwest. Therefore, there will be coverage issues
with storms on Wednesday and there will be more of a scattered
flavor to storms vs. being widespread and have just 40-60% PoPs.
There is still some low level jet energy across the region that will
increase the shear across the region and enhance the severe
organization potential. In the end, there will be some strong to
severe storms in the region and with the high instability and steep
lapse rates, strong wind and large hail will be the favored threats.
Much of the area is delineated in a Day 3 Slight Risk for severe
weather from the Storm Prediction Center.

For Thursday and Thursday night, PoP chances will decrease during
the day on Thursday as the cold front pushes southeast across the
forecast area and high pressure builds into the region. Temperatures
will return closer to normal with this cooler air mass.

&&

.LONG TERM /FRIDAY THROUGH SUNDAY/...
The long term forecast period is trending more uncertain for the
weekend weather. A strong upper ridge will be over the region with
high pressure at surface on Friday. However, an upper trough will
move through the Ohio Valley and undercut the upper ridge. This
feature may advance a warm front north into the forecast area and
allow for rain chances to return. If this occurs, this may allow the
forecast area to be in a more progressive region of the general
weather pattern, where another upper trough and low pressure system
will enter on Saturday and with another upper trough to the
northwest on Saturday night. Therefore, have chance PoPs through the
weekend. However, if the upper ridge amplifies enough, it could set
up a blocking pattern of sorts and keep the better rain chances
south for a time this weekend. In the end, will go with a forecast
with temperatures slightly above normal and slight to mid chance
PoPs through the period.

&&

.AVIATION /12Z Monday THROUGH Friday/...
VFR is expected through the TAF period. A few showers/storms
may develop along the lake breeze this afternoon, which could
move within the vicinity of KCLE and possibly KTOL/KMFD. Only
have VCSH at KCLE for now, but may to expand showers west and
south as confidence increases. Non-VFR visibilities are
possible if any showers/storms manage to move directly over a
terminal. Showers may move into the vicinity of western
terminals late tonight or very early Tuesday morning, but
confidence in the placement and timing of precip is low.

Light and variable winds early this morning will become
south/southwesterly and increase to 5 to 10 knots this
afternoon. Wind direction will likely be more variable at
KCLE/KERI due to the lake breeze.

Outlook...Mainly VFR expected outside of any thunderstorms.
Isolated thunderstorms are possible during the afternoon and
early evening hours Tuesday. Scattered to numerous
thunderstorms are more likely Wednesday afternoon into Wednesday
night.

&&

.MARINE...
A warm front will move north of the lake today with a weak gradient
remaining across the region. Therefore, will start with south to
southeast winds for a large portion of the lake, but winds in the
nearshore this afternoon could become onshore with a lake breeze
developing across the region. A weak low will pass north of the lake
tonight and allow for south to southwest flow to return to the
basin. A low pressure system will develop over the Midwest on
Tuesday and the pressure gradient will increase across the lake on
Tuesday night into Wednesday and winds will strengthen in response.
The southwest flow on Wednesday afternoon could mix pretty well and
wind strength could be close to needing a Small Craft Advisory
headline. A cold front will extend across the lake on Wednesday
night and winds will shift to the west and then north as high
pressure builds over the lake. The surface high will move east of
the lake on Friday and northeast flow will be favored and onshore
flow could be enhanced with a lake breeze.

&&

.CLIMATE...
High temperatures will approach record values today and Tuesday.

Daily Record High Maximum Temperatures

Date    Toledo         Mansfield      Cleveland      Akron          Youngstown     Erie
05-20   92(1962)       89(1962)       91(1962)       91(1934)       91(1934)       88(2021)
05-21   93(1941)       89(1941)       89(1941)       91(1934)       89(1934)       88(1911)

&&

.CLE WATCHES/WARNINGS/ADVISORIES...
OH...Air Quality Alert until midnight EDT tonight for OHZ010>014-
     020>022-089.
PA...None.
NY...None.
MARINE...None.

&&

$$

SYNOPSIS...Maines
NEAR TERM...Maines
SHORT TERM...Sefcovic
LONG TERM...Sefcovic
AVIATION...Maines
MARINE...Sefcovic
CLIMATE...