931
FXUS61 KCLE 290606
AFDCLE

Area Forecast Discussion
National Weather Service Cleveland OH
206 AM EDT Wed May 29 2024

.SYNOPSIS...
A surface cold front will move southeast through the area overnight
as a weak area of low pressure lingers across the Upper Ohio Valley
through Wednesday. High pressure will then build across the Great
Lakes on Thursday and persist into the weekend.

&&

.NEAR TERM /THROUGH TODAY/...
12:30 AM Update...

Sped up the onset of higher PoPs in NW Ohio over the next 2
hours to account for the band of showers and embedded thunder,
otherwise, the forecast remains on track for overnight.

10:00 PM Update:
A few showers and storms from Marion to Holmes County, otherwise the
area is generally dry. Isolated to widely-scattered showers are
spreading into Northwest OH and western Lake Erie. A more organized band
of showers and storms ahead of a vort max and weak surface low will
spread into the I-75 corridor around or just after midnight. As the vort
max and surface low move east-southeast expect this area of showers and
thunder to pinwheel across most of the area through early Wednesday
afternoon, though far Northeast OH into Northwest PA may largely stay
north of this batch of showers and thunder. As we get into the afternoon
coverage of showers and storms should decrease from north-northwest to
south-southeast as the vort max and surface low begin to exit, though as
this occurs any sunshine will result in destabilization, which could
allow additional pop-up showers and storms to re-develop outside of a
lake shadow immediately south of Lake Erie in the afternoon. As we get
towards sunset Wednesday we should quickly dry out. Tweaked POPs a bit
to reflect this thinking though the changes weren`t too significant.

With chilly air aloft small hail and gusty winds will remain possible
with some thunderstorms through Wednesday...especially during the
afternoon on Wednesday when low-level lapse rates will be steepest and
instability greatest. The vort max, surface low, fairly strong 0-3km
CAPE and weak shear may support a non-supercellular funnel or two across
our southern counties on Wednesday though no severe weather is expected.
Slow cell motions could allow for locally up to 2" of rain under the
most-persistent downpours / storms later tonight into Wednesday, which
could lead to localized minor flooding concerns.

Previous Discussion:
Scattered showers and thunderstorms have developed across the region
this afternoon, aided by a mid-level shortwave and diurnal heating. The
most persistent updrafts continue to be seen across NW OH into MI where
more favorable instability (~500 J/kg MLCAPE) is found. Elsewhere,
periodic lightning is possible through the rest of the afternoon, though
the potential will remain more isolated. Small hail will continue to be
possible in any stronger storms through the rest of this afternoon.

Attention tonight then turns to a slightly stronger mid-level trough
which will swing southeast across the Upper Midwest and Lower Great
lakes tonight into Wednesday. At the surface, a weak low pressure
will slowly pivot east along the US-30 corridor, sparking additional
showers and thunderstorms by late Wednesday morning into the
afternoon. Precipitation coverage will be higher versus today, with
nearly stationary storm motions at times. Will need to monitor rain
rates, particularly between the I-75/71 corridors with the HREF LPMM
suggesting isolated rain amounts of 2-3 inches possible in the most
persistent rains.

&&

.SHORT TERM /TONIGHT THROUGH FRIDAY NIGHT/...
Quiet part of the forecast as the upper level trough departs with
Canadian high pressure settling into the Great Lakes. Still a chilly
day without any presence of warm air advection just with the
positioning of the surface high over the CWA through Friday night.
Dry forecast through the entirety of the short term forecast period
and an improvement to the afternoon high temperatures from Thursday
60s to lower 70s into Friday lower to upper 70s, although some
portions of NW PA still may have a little trouble eclipsing the 70F
mark. Plenty of sun Thursday and Friday with some high level clouds
moving in Friday night. Low dewpoints, clear skies, and winds going
calm equate to 40s away from the lake Thursday night. Some upper 30s
possible far eastern portions of the NW PA counties in the valleys.
No frost for now and think temperatures should stay high enough,
but will need to watch this carefully as the valleys could radiate
efficiently. Nights are much shorter this time of year, however, so
that would work against this.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
A little more unsettled into the weekend with an upper trough axis
embedded in the zonal flow working its way through the are late
Saturday into Saturday night. Still have diverging solutions going
beyond this time frame, however. Zonal flow should persist through
the period with warm frontal interaction for the end of the weekend
into early next week. Temperatures continue to rise through the
period into the low to mid 80s by Monday.

&&

.AVIATION /06Z Wednesday THROUGH Sunday/...
Showers will gradually move eastward early this morning bringing
periods of MVFR, with the best chances in west and southwest
areas like KTOL, KFDY, KMFD, and KCAK. Otherwise, mainly dry and
VFR conditions are expected through sunrise except for KERI
where some lower clouds and mist will occur at times. From mid
morning into the afternoon today, showers and embedded thunder
will expand as an upper low crosses the region combined with
daytime heating. Coverage and timing is again uncertain today,
but most sites will see precip at times, with the greatest
frequency being away from the lake at KFDY, KMFD, KCAK, and
KYNG. Brief drops to MVFR or lower will occur in the heaviest
convective showers, with mainly VFR in between, but these drops
will be tough to time. Drier air will finally work in this
evening as high pressure builds in, leading to VFR areawide
tonight.

Light and variable winds early this morning will turn N and
increase to 10-20 knots later this morning through the
afternoon.

Outlook...Non-VFR may return Saturday night into Sunday in isolated to
scattered showers and thunderstorms.

&&

.MARINE...
Winds become northerly tonight 5-10kts, increasing to 10-20kts
behind a cold front Wednesday. While waves become 1-3ft in lower
winds tonight, expecting them to increase to 3-5ft for the western
and central basin Wednesday where another Small Craft Advisory may
be needed. Onshore winds will decrease Wednesday night through
Thursday night as high pressure moves into the Great Lakes, with
wave heights coming down as well during that time frame. Friday,
winds become light and variable with waves less than a foot.

&&

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

&&

$$

SYNOPSIS...Kahn
NEAR TERM...Garuckas/Kahn/Sullivan
SHORT TERM...26
LONG TERM...26
AVIATION...Garuckas
MARINE...26