150
FXUS61 KCLE 192335
AFDCLE

Area Forecast Discussion
National Weather Service Cleveland OH
735 PM EDT Fri Jul 19 2024

.SYNOPSIS...
A ridge continues to impact northern Ohio and northwest Pennsylvania
through Sunday night as the core of the ridge remains draped across
the southwestern and eastern Great Lakes region. The ridge begins to
exit slowly and generally eastward this Monday through Tuesday as a
warm front begins to approach our area from the Tennessee and Ohio
Valleys.

&&

.NEAR TERM /THROUGH SATURDAY NIGHT/...
730 PM Update...
Scattered clouds should clear near or shortly after sunset and
expect clear skies through tonight. Can`t rule out some patchy
fog in interior NE OH/NW PA as mentioned in the previous
discussion. No changes needed with this update.

Previous Discussion...
Cyclonic flow aloft, varying between SW`erly and NW`erly, and
embedded shortwave disturbances affect our region through
Saturday night. Periodic mid/upper-level cloud cover is
expected, especially tonight through Saturday night, as
mid/upper-level and moist isentropic ascent precedes the axes of
the aforementioned shortwave disturbances. At the surface, a
ridge continues to impact our CWA as the core of the ridge
remains draped across the southwestern and eastern Great Lakes.
Fair weather persists as a stabilizing subsidence inversion
accompanies the low-level ridge. Overnight lows are expected to
reach mainly the 50`s to lower 60`s around daybreak Saturday and
mainly the mid 50`s to mid 60`s around daybreak Sunday as cloud
breaks, surface dew points near 50F to 55F, and weak or calm
surface winds promote efficient radiational cooling during
evening hours through daybreak. Localized river valley steam fog
is forecast to develop in interior portions of far-NE OH and
especially NW PA around daybreak Saturday and Sunday,
respectively. Fog will dissipate soon after daybreak via onset
of diurnal convective mixing of the boundary layer tapping into
drier air just aloft.

On Saturday, late afternoon highs are expected to reach the upper
70`s to mid 80`s as diurnal heating/convective mixing of the
boundary layer accompany 850 mb temperatures near 12C to 15C.
Similar to today, the coolest highs on Saturday are expected over
and within several miles of Lake Erie since a very weak synoptic
MSLP gradient and daytime heating of surrounding land will once
again allow a lake breeze to occur during the late morning through
early evening. Given a N`erly synoptic MSLP gradient in our CWA,
this lake breeze is expected to exhibit maximum inland extent of at
least five to ten miles; similar to today`s lake breeze.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
A mainly quiet short term period is in store across the region as
surface high pressure weakens and retreats towards New England
through Monday. A moist air mass across the southern CONUS will
slowly advect northwards into the region beginning Sunday night. A
developing weak upper-level trough across the Missouri Valley may
have enough energy to kick off some isolated showers and storms
Monday afternoon, although low-level moisture is expected to remain
limited, with dew points in the upper 50s to lower 60s. Seasonable
highs in the mid-80s are expected for both Sunday and Monday with
partly to mostly cloudy skies.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
More active weather is anticipated for the long term period as
ensembles agree that a moist air mass will remain in place, coupled
with increasing amounts of upper-level jet energy. Severe storm
chances appear low as widespread cloud cover and poor mid-level
lapse rates should limit MLCAPE to generally 1000 J/kg or less.
Overall, shear should be fairly marginal, though occasional
shortwaves may introduce mid-level southwesterly flow of 25 to
perhaps 35 knots at times, particularly Tuesday through Thursday
which could result in organized thunderstorm clusters during the
afternoon and evening hours. In addition, locally heavy rain will be
possible with PWATs in the 90th percentile (1.60 to 1.80 inches) and
skinny CAPE profiles.

In terms of coverage, scattered to widespread showers and
thunderstorms are expected Tuesday through Thursday, particularly
during peak heating in the afternoon and evening hours. At some
point, surface high pressure is expected to build in from the north
across the Great Lakes towards the end of the week and into the
weekend, bringing an end to the wet pattern.

&&

.AVIATION /00Z Saturday THROUGH Wednesday/...
VFR is expected through the TAF period. Winds will be light and
variable overnight with northerly winds 5 to 10 knots expected
with the lake breeze from KCLE to KERI Saturday afternoon.

Outlook...VFR expected through Monday morning. Isolated to
scattered showers/thunderstorms with non-VFR possible Monday
afternoon through Wednesday.

&&

.MARINE...
A quiet marine period is in store across Lake Erie through the
weekend and into early next week with no headlines anticipated.
Surface high pressure will gradually weaken through the weekend and
be replaced with weak surface troughing which will persist into
early next week. For the most part, winds will be 10 knots or less,
favoring an onshore component in the afternoon/early evening hours
associated with the lake breeze.

&&

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

&&

$$

SYNOPSIS...Jaszka
NEAR TERM...Jaszka/Maines
SHORT TERM...Kahn
LONG TERM...Kahn
AVIATION...Maines
MARINE...Kahn