fxus61 kcle 171805
area forecast discussion
national weather service cleveland oh
205 pm edt wed aug 17 2022
an upper level trough will remain over the eastern great lakes
today, then pivot northeast across new england tonight. surface
high pressure will build east across the great lakes thursday
and friday. low pressure will approach the western great lakes
on saturday then slowly move east across the region over the
.near term /through thursday/...
scattered showers have developed across ne oh this afternoon and
expect this to continue through the afternoon/early evening
before dissipating with the loss of diurnal heating this
evening. no significant changes needed with this update, as the
previous forecast remains on track.
a broad upper level trough remains overhead this morning with a
piece of energy rotating across northeast ohio. scattered
showers continue to expand westward with easterly flow in the
moist layer near 700mb, forecast to back to more northeasterly
through the morning. models have struggled with handling of this
light shower activity and expect it may continue through 10 am
or so when energy aloft will have shifted southeast of the area.
at that time a lull in activity is expected before diurnal
heating kicks in. instability will be limited with to 500-1000
j/kg of ml cape today, highest in pa. showers will be scattered
with generally isolated thunderstorms for another day, with a
little better coverage closer to the trough in ne ohio/nw
pennsylvania. although clouds are fairly thick this morning,
expecting them to thin with some heating this afternoon with
high temperatures in the mid 70s to near 80 in nw ohio.
a pattern change gets underway tonight as the upper level low pivots
northeast across new england, allowing heights to start to climb on
thursday. in the low levels, high pressure from the upper midwest
will expand east across ohio. light flow tonight will allow for
land breezes to develop with convergence over lake erie,
although this time focused just offshore from cleveland to
geneva-on-the-lake. can not rule out a stray shower near lake
erie and have held onto a low pop for tonight. this weak surface
troughing will push inland on thursday ahead of building high
pressure, with a few afternoon showers possible once again,
although with lesser coverage and confined to inland ne ohio and
nw pennsylvania. less cloud cover is expected with mostly to
partly cloudy skies which will allow temperatures to trend 2-3
degrees warmer that wednesday.
.short term /thursday night through saturday night/...
fair weather is likely thursday night through friday as stabilizing
high pressure at the surface and aloft presses eastward and
influences our region. low temperatures should reach mainly the mid
50`s to lower 60`s around daybreak and be followed by late afternoon
highs in the lower to mid 80`s on friday. the coolest highs should
be focused in the higher terrain of northwest pa and along the lake
erie shore, where a lake breeze should develop during the afternoon
and early evening as daytime heating of surrounding land and
overlying air occurs amidst a weak synoptic scale mslp gradient.
isolated rain showers and thunderstorms are possible south of
roughly the u.s. route 30 corridor friday night, especially after
midnight, as a shortwave trough begins overspreading our cwa from
the southwest and is accompanied by a weak surface trough. the
shortwave disturbance will be preceded by moist isentropic ascent
aloft, which should release weak elevated cape. humidity will begin
to increase as low-level warm and moist air advection occurs along
the backside of the aforementioned high pressure ridge departing
eastward. lows should reach mainly the upper 50`s to mid 60`s around
daybreak saturday morning.
isolated to scattered showers and thunderstorms are expected on
saturday as the aforementioned shortwave trough advances farther
northeastward through the rest of our cwa through early afternoon,
another trough aloft begins approaching from the upper midwest and
western great lakes, and weak surface troughing persists in our
area. a combination of daytime heating, weak to moderate boundary
layer destabilization, and colder air aloft accompanying the troughs
should allow convection to develop via self-destructive sunshine. in
addition, a lake erie lake breeze front should contribute to
convection initiation during the afternoon and early evening hours.
daytime highs should reach the lower to upper 80`s. shower and
thunderstorm coverage should become isolated later saturday evening
and saturday night as the boundary layer stabilizes via nocturnal
cooling, yet moist isentropic ascent aloft persists and probably
releases weak elevated cape. overnight lows should settle into
primarily the lower to mid 60`s.
.long term /sunday through tuesday/...
our weather remains unsettled through tuesday as the trough aloft
slowly overspreads our cwa from the west and is accompanied by moist
isentropic ascent aloft and weak elevated instability.
simultaneously, weak surface troughing lingers in our region. a cool
front should drift southeastward across lake erie and our cwa monday
into tuesday and act as a focus for shower and thunderstorm
development. shower and storm coverage should be greatest each
afternoon and early evening since daytime heating, weak to moderate
boundary layer destabilization, and colder air aloft with the trough
should allow convection to continue to develop via self-destructive
sunshine. daily afternoon highs should range from the mid 70`s to
lower 80`s. overnight lows should reach mainly the lower to mid 60`s
monday night and tuesday night.
.aviation /18z wednesday through monday/...
expect vfr through this evening, although there may be spotty
non-vfr with any scattered showers that move directly over
terminals. coverage is a bit too scattered and disorganized to
warrant anything more aggressive than vcsh at this time.
amendments may be needed to introduce -shra if confidence
increases. showers should taper off near or after sunset. patchy
fog may develop at southeastern terminals between 09z and 13z
thursday morning, which could result in a period of non-vfr
visibilities at kmfd/kcak/kyng. otherwise, expect vfr conditions
through the remainder of the taf period.
north to northeast winds 6 to 12 knots will become light and
variable tonight. expect light and variable winds to persist
through the remainder of the taf period.
outlook...non-vfr possible in isolated to scattered showers and
thunderstorms thursday afternoon and again saturday afternoon
a weak trough lingers over lake erie before weak high pressure
builds eastward this thursday and friday. by this weekend, a weak
low will begin approaching lake erie from the upper midwest as the
ridge exits eastward. variable winds of about 10 knots or less and
waves of 2 feet or less are expected through saturday. winds should
trend southeasterly to southerly around 5 to 10 knots saturday night
into sunday and waves should remain 2 feet or less. of note,
marginal lake-induced instability may allow lake-effect showers and
waterspouts to form along a land breeze convergence zone this
morning and again tomorrow morning.