073
FXUS61 KCLE 241321
AFDCLE

Area Forecast Discussion
National Weather Service Cleveland OH
921 AM EDT Tue Sep 24 2024

.SYNOPSIS...
A warm front will lift north across the local area today as low
pressures moves northwest of the area tonight. This low will
extend a weak cold front across the area on Wednesday. High
pressure will build from the northwest for Thursday.

&&

.NEAR TERM /THROUGH WEDNESDAY/...
9:20 AM Update...
Steady rainfall with embedded thunderstorms are continuing to
move across the region ahead of a warm front draped across
Central Indiana and Southwest Ohio this morning. Rainfall
amounts early this morning along and south of US-30 range
between 1.00 and 1.50 inches which prompted a Flood Warning to
be issued through 12:15 PM today for Ashland, Medina, Stark,
Summit, and Wayne counties. Showers and thunderstorms should
persist through this afternoon ahead of the warm front.

7:00 AM Update...
An efficient batch of rain is moving across the forecast area
this morning. Rainfall amounts this morning have largely been in
the 0.50-1.00" range with some efficiency thanks to warm cloud
procresses as the warm front lifts north. Additional shower and
storm development is occurring across western Ohio and expect
more rain to move through the area during the morning and early
afternoon hours.

Previous Discussion...
The first batch of rain with the warm front is entering the
southwest portion of the forecast area this morning. This will
spread through at least I-77 over the next several hours. A
larger batch of rain with some embedded thunder is entering
Southwest Ohio this morning and will largely remain south of the
area; however, additional rain showers will try to build to the
north of this feature and cascade across the area during the
late morning hours and have categorical PoPs through 18z or so.
There appears to be a lull in activity across the region this
afternoon before more showers and storms develop with a wave
of energy that will outrace the main trough and support the low
pressure system northwest of the area.

Unfortunately, believe that the amount of rain and cloud cover
will be quite substantial early in the day and have lowered
temperatures from the prior forecast and will have highs just
limp into the lower 70s this afternoon. With this change,
believe that there will be less instability for storms to work
with and believe that the severe potential is trending down.
There is still some notable shear with 30-40 kt of 0-6 km bulk
shear and that could help organize something with a bite to it.
In the end, the Day 1 Outlook from the Storm Prediction Center
has shifted the Marginal Risk south to align where there will be
at least some better instability to get some storms with a bite.
The southern portion of the forecast area remains in the
Marginal Risk and there will be a chance for a storm with
damaging wind potential.

Rain is expected to scatter out from west to east tonight as the
main low departs to the north of the region. This low will
extend a weak cold front across the area on Wednesday and could
be a source to rejuvenate shower activity over the eastern third
of the forecast area on Wednesday afternoon. Have likely PoPs
returns in for far NE OH and NW PA with the front. Low
temperatures tonight will stay elevated in the 60s with clouds
and rain in the region. Highs on Wednesday will be pretty close
to today, perhaps a touch higher with more areas staying dry.

&&

.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY NIGHT/...
Cold front will exit to the east Wednesday night, allowing surface
high pressure to build over the region for Thursday. Any lingering
showers will taper off by Thursday morning and dry weather is
favored through at least Thursday afternoon. By Thursday night, a
complex upper level pattern will develop over the southeastern CONUS
as a tropical low moves inland from the Gulf Coast. Moisture will
likely stream north into the Tennessee and Ohio valleys late
Thursday and Friday, although there`s still uncertainty in whether
or not the moisture reaches as far north as the local area.
Maintained low-end chance (around 30 percent) PoPs for southwestern
portions of the CWA with slight chance PoPs else northeast into
portions of northeastern Ohio. Moisture may increase a bit more
Friday night as remnants of an upper low lift towards the area so
PoPs increase slightly, but it`s possible that the majority of the
short term period remains dry if moisture ends up being suppressed
to the south and southwest of the area.

Highs will generally be in the mid 70s to lower 80s throughout the
period, although a rainier outcome may result in slightly cooler
temperatures in the southwestern part of the CWA. Overnight lows
will be in the upper 50s to lower 60s each night.

&&

.LONG TERM /SATURDAY THROUGH MONDAY/...
A vertically stacked low will meander somewhere across the Middle
Mississippi and/or western Tennessee/Ohio valleys this weekend into
early next week, although there is still a great deal of uncertainty
in the placement/strength of the low and the resulting precipitation
chances across the CWA. Periodic showers and perhaps a few
thunderstorms are possible throughout the long term period, but
maintained low PoPs until confidence increases in upcoming days.
Above normal temperatures will gradually moderate to near normal
values as the weekend progresses, but similar to the short term
period, a rainier/cloudier forecast may result in cooler
temperatures than currently forecast.

&&

.AVIATION /12Z Tuesday THROUGH Saturday/...
An efficient batch of showers and some embedded thunder will
continue across the airspace this morning. A variety of flight
conditions are occurring with the rain and low clouds from VFR
near the lakeshore to IFR/LIFR in the worst conditions in NE OH.
Additional rain is developing across western Ohio this morning
and will continue to spread into the terminals and allow for
more non-VFR. There will be a slight reprieve in rain during
the afternoon before more rain is expected to develop with a TS
chance with the surface low moving northwest of the area. Have
timed some rain and VCTS with the TAFs except KERI this evening.
Rain will clear late in the period but low ceilings and even
some fog will develop late tonight into Wednesday and more IFR
should be expected. Winds will be east to southeast with the
warm front this morning and winds will shift to the south behind
the front. There will be some strengthening winds in NE OH and
NW PA in the warm sector of the front and gusts to 25-30 kt are
possible and have gusts mentioned in the KERI TAF.

Outlook...Non-VFR conditions may linger into Wednesday with
residual rain, low ceilings, and fog in the region. Strong
northeast winds are expected across the region on Friday.

&&

.MARINE...
South winds 6 to 12 knots this morning will become southeasterly and
increase as a warm front lifts into the region this afternoon.
Downsloping effects in the eastern basin will produce winds of 20
to 25 knots with 10 to 20 knots more likely west into the central
basin. Although higher waves will be focused into the open/Canadian
waters, strong offshore winds have necessitated a Small Craft
Advisory from Geneva-on-the-Lake, OH to Ripley, NY between 21Z today
and 12Z Wednesday. Will need to monitor winds from roughly Avon
Point to Geneva-on-the-Lake as the afternoon and evening progress,
but currently thinking nearshore winds will remain in the 15 to 20
knot range.

Winds gradually diminish to 10 to 15 knots and shift to the
southwest as a cold front approaches the lake early Wednesday
morning and expect flow to become northwesterly behind the front
Wednesday night. Flow will quickly shift to the northeast as high
pressure builds over the lake Thursday. The pressure gradient will
tighten significantly as low pressure moves inland from the Gulf
Coast towards the end of the week and additional Small Craft
Advisories are likely as northeast winds increase to 15 to 25 knots
Friday into Saturday.

&&

.CLE WATCHES/WARNINGS/ADVISORIES...
OH...None.
PA...None.
MARINE...Small Craft Advisory from 5 PM this afternoon to 8 AM EDT
     Wednesday for LEZ148-149.

&&

$$

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