195
FXUS61 KCLE 271135
AFDCLE

Area Forecast Discussion
National Weather Service Cleveland OH
735 AM EDT Mon Jul 27 2026

.WHAT HAS CHANGED...
The evolution of MCS development tonight and how it will translate
through the day today and later tonight will continue to be in
flux.

&&

.KEY MESSAGES...
1) Rounds of convection possible today and tonight, hinging on the
initial systems this morning.

2) Cooler airmass and high pressure into the end of the week.

&&

.DISCUSSION...
KEY MESSAGE 1...
All eyes this morning will be on the developing thunderstorm
complexes currently in northern Minnesota and over eastern Lake
Superior. Evolution has been slow thus far and IR imagery showing
cloud top cooling is minimal at this point although growing in size
over Whitefish Bay, and expect enhancement over the next few hours.
Bulk shear vectors will take these developing complexes
southeastward into the southern Great Lakes, where CAMs/rapid update
models have had a hard time providing any consistency to their
solutions on where MCSs will go and if/when they decay. As they move
towards the Cleveland CWA, plenty of elevated instability to work
with, but atmospheric layer above the boundary layer needs some work
in terms of RH as it is pretty dry for the time being. Outside of
the drier layer of air aloft, surface dewpoints in the mid 60s and
usable mid level lapse rates exist. However, the timing of the MCS
works against it for our area as it tracks southeastward towards
dawn, and will likely suffer decay as cloud tops are forced to warm
with minimal low level jet energy in place. That said, there is an
expectation of a few lingering clusters of showers or showers with
isolated thunder this morning from the Lake Superior MCS. Further
west, the Minnesota system is one that hi res models and CAMs are
suggesting will survive into the daytime, and could affect our CWA
later today. Ultimately, the forecast challenge here is that the
rest of the day and into the overnight is likely going to rely on
what happens with these initial systems, how long it takes or if the
atmosphere needs to recover from them, if there are lingering wake
MCVs, etc. Expect an evolving forecast, but know that the chances
for convective activity will exist from this afternoon into the
overnight hours.

KEY MESSAGE 2...
A cold front will come through Tuesday morning with a wholesale
airmass change with cooler and drier air in place. Additional upper
trough axes will swing through the CWA north to south, and the
onshore flow coupled with this could generate showers with some lake
enhancement as the 850mb temperatures drop into the lower teens.
High pressure will then settle into the southern Great Lakes for the
end of the week with temperatures in the mid 70s to lower 80s
through Thursday.

&&

.AVIATION /12Z Monday THROUGH Friday/...
Areas of MVFR BR in patchy fog this morning across inland
terminals. Terminals with MVFR visibility should lift to VFR
within the next 1-2 hours. Have a few TEMPO groups in the TAF
sites to account for BR through 13Z/Mon.

Looking upstream the possibility of showers and thunderstorms
at western terminals this morning has significantly decreased
and have removed any TS mention at KTOL/KFDY for this morning.
Looking ahead, there remains a large model spread between hi-
res members for additional rounds of showers and thunderstorms
across the Great Lakes and Ohio Valley region during this
afternoon into the evening/overnight. One possible outcome would
be for the convection currently diving south across Lake
Superior to enter terminals ~20z/Mon. This cluster is progged to
dive southeast across terminals through ~03Z/Tue. Will need to
continue to monitor the progression of this complex as it sinks
southeast during the day today. Given confidence levels, have
PROB30 this evening at all terminals for any TS impacts.

Southwesterly winds 7-10 knots with isolated 10-12 knots across
western terminals today. Southerly winds 8-12 knots this evening
slowly shift northerly overnight tonight into Tuesday morning.

Outlook...Non-VFR possible with periodic showers and
thunderstorms this morning through Tuesday.

&&

.MARINE...
Light winds will increase to southwest winds 8-12 knots this
morning. Winds will shift southerly and gradually increase to
15-20 knots this evening before eventually turning northerly at
20-25 knots by Tuesday morning. Northerly winds continue
through Wednesday. Given elevated onshore flow wave heights are
expected to build to 3-6 feet both Tuesday and Wednesday. Will
likely need Small Craft Advisories and Beach Hazard Statements
for this timeframe. High pressure will approach from the west
allowing for northerly winds 15-25 knots to diminish to 10-15
knots by Thursday morning before winds become light and variable
on Friday.

A series of weakening thunderstorm complexes moving in the
vicinity of Lake Erie remain possible through tonight. Winds and
waves may be locally higher in any thunderstorm that does move
over the lake.

&&

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

&&

$$

DISCUSSION...26
AVIATION...13
MARINE...13