-- Discussion containing changed information from previous version are highlighted. --
207
FXUS61 KCLE 231729
AFDCLE

Area Forecast Discussion
National Weather Service Cleveland OH
129 PM EDT Thu May 23 2024

.SYNOPSIS...
A weak cold front will push south of the area this morning with high
pressure building in behind it. The stalled frontal boundary near
the Ohio River will lift north as a warm front on Friday. Low
pressure will cross the Central Great Lakes on Saturday, pulling a
cold front south behind it.

&&

.NEAR TERM /THROUGH FRIDAY/...
9:35 AM Update...
No major changes made to the forecast. Clouds have cleared with
a mostly sunny morning and afternoon expected today. High
temperatures will rise into the upper 70s to lower 80s this
afternoon. A warm front will begin to lift northward toward
southern counties in the local area today. This front may allow
for isolated pop up showers and thunderstorms to develop as
peak heating will allow for MLCAPE values to rise into the
500-1000 J/kg range.

7:00 AM Update...
As clouds have cleared, some valley fog has developed in select
locations, mainly in northeast Ohio. Any areas of reduced
visibilities should improve quickly now that the sun has risen.

Previous discussion...
Water vapor imagery shows the deep moisture axis exiting the area to
the east this morning. The surface cold front bisects the area from
about Meadville to Marion at 4 AM and will push south this morning.
Skies will be mostly sunny today as high pressure builds in behind
the front. Moisture will start to sneak back north into our far
southern counties this afternoon as a shortwave moves through the
flow aloft across Central Ohio. Can not rule out an isolated shower
or thunderstorms in mainly Knox or Holmes Counties late this
afternoon into this evening but both instability and a forcing
mechanism will be limited so will cap pops at 20 percent. High
temperatures will be 3-7 degrees cooler than yesterday but will
remain slightly above normal. Most areas will experience light
southwest winds except lake breezes developing during the afternoon
near Lake Erie. Lows tonight will follow suit and also be slightly
above normal in the mid to upper 50s.

On Friday low pressure will track out of the Plains into the Central
Great Lakes. The stalled frontal boundary to our south will lift
north as a warm front. A fairly strong cap is expected to be in
place around 750mb with shortwave ridging aloft. The cap will start
to erode from west to east as moisture arrives but timing looks more
favorable by Friday evening so only held onto some low slight chance
pops during the afternoon in the southwestern counties. Dewpoints
will be relatively low, ranging from near 50 in the east to
approaching 60 in the south by late afternoon. High temperatures
trend back up again the low to mid 80s.

&&

.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY NIGHT/...
A warm front will continue to lift north across the area Friday
night as a nearly vertically stacked low with an occluding low at
the surface slowly lifts northeast across the Upper Midwest/Great
Lakes. This low will also nudge a cold front east towards the CWA
overnight Friday into Saturday morning which should cross the area
during the day Saturday. PoPs will increase in the warm sector
(mainly in western Ohio) Friday before shower and isolated
thunderstorm chances increase areawide with the frontal passage
Saturday. The best instability (albeit marginal) will be Friday
night and do not anticipate severe weather due to the unfavorable
diurnal timing of precipitation. Showers should be in eastern zones
if not already moving out of the area by early Saturday evening with
dry weather briefly returning for Saturday night as a weak ridge
builds east across the area and the cold front pauses over the Ohio
Valley.

On Sunday, an upper trough will eject out of the Plains and into the
Midwest and at the surface, low pressure will develop and begin to
deepen over the central Mississippi Valley. The low will deepen
further as it lifts northeast towards the Great Lakes throughout the
day and the cold front will lift back north over the area as a warm
front through Sunday night. A shortwave will likely accompany the
warm front which will provide extra lift for showers and
thunderstorms as early as Sunday afternoon but more likely Sunday
evening into Sunday night. As of now, the chance of organized
convection looks relatively low due to the best instability
remaining to the southwest of the area, but will need to keep an eye
on thermodynamics in the upcoming days.

Highs will generally be in the upper 70s to lower 80s over the
weekend with overnight lows in the low to mid 60s Friday and Sunday
night and mid to upper 50s to lower 60s Saturday night.

&&

.LONG TERM /MONDAY THROUGH WEDNESDAY/...
Unsettled weather will continue through Memorial Day as an upper
trough (perhaps upper level low at this point) and deep surface low
track over the central Great Lakes. Still a bit of uncertainty with
overall setup amongst deterministic guidance; the ECMWF and Canadian
place the low and best forcing aloft to the north of the area,
whereas the latest run of the GFS is an outlier with a much slower
and slightly more southern track. Regardless, showers and possibly
thunderstorms are likely through most of the day and it will be
quite breezy with wind gusts to about 30 mph possible. The potential
for organized convection over the area will depend on the track of
the low. If it takes a more northward track, there may be a better
opportunity for destabilization Monday. The dynamics of the system
will certainly provide quite a bit of wind shear, so organized
storms cannot be ruled out.

PoPs may begin to taper off in western zones as early as Monday
evening as the surface low occludes and lifts northeast into Ontario
and Quebec, but persistent cyclonic flow associated with the upper
low will push several shortwaves across the eastern Great Lakes
through the middle of the week. The enhanced lift in addition to
850mb temperatures falling to around 5C will result in continued
chances of lake-enhanced rain showers and a slight chance of
thunderstorms Tuesday and Wednesday. Temperatures will decrease
during the long term period with highs in the low to mid 70s Monday
giving way to 60s and lower 70s Tuesday and Wednesday. Overnight
lows will be in the 50s Monday and Tuesday night.

&&

.AVIATION /18Z Thursday THROUGH Tuesday/...
-- Changed Discussion --
VFR will persist across terminals through the TAF period. Some
high level clouds will gradually moving in overhead from the
south as a warm front lifts northward. Can`t rule out patchy
MVFR fog at MFD/CAK overnight tonight after 06Z, but confidence
was too low to include in the TAF.

Generally southwesterly winds 5-8 knots this afternoon will
become light and variable overnight tonight. Winds become
southeasterly while increasing to 5-10 knots Friday afternoon.

Outlook...Scattered showers and storms possible Friday night and
Saturday. Chance of thunderstorms Sunday night into Monday with
non-VFR possible.
-- End Changed Discussion --

&&

.MARINE...
Southwest winds 5 to 10 knots are expected today with a brief period
of onshore flow likely with the development of a lake breeze this
afternoon. Generally expect variable winds under 10 knots tonight
into Friday morning before flow becomes southeasterly and increases
to 10 to 15 knots as a warm front lifts north/northeast towards Lake
Erie. The warm front will be followed by a cold front during the day
Saturday and winds will shift to the southwest Saturday morning and
the northwest Saturday night. East/northeast flow develops with
winds increasing to 10 to 20 knots as yet another warm front lifts
towards the lake Sunday. Winds and waves are trending higher for
Memorial Day as low pressure moves across the Great Lakes. Currently
thinking the center of the low will cross lower Michigan and move
into southern Ontario, which would drag a cold front across the lake
during the day Monday. Offshore winds to 20+ knots is becoming
increasingly likely with west winds 15 to 20 knots expected by
Saturday evening. Unless winds trends lower, Small Craft Advisories
and Beach Hazards Statements as early as late Sunday night and most
likely during the day Monday. Headlines may continue into
Tuesday.

&&

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

&&

$$

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