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Area forecast discussion 
National Weather Service Cleveland Ohio
620 PM EDT Friday Jul 29 2016

Synopsis...
a stationary front will remain across Northern Ohio and western
Pennsylvania through Sunday morning. Weak waves of low pressure
will ride along the front. High pressure will build southeast
across the area Sunday night. The high will move southeast by mid
week allowing for a return back to warmer temperatures.

&&

Near term /through Saturday/...
heaviest rain has finally tapered off somewhat. Still have showers
from southern Wood County east into Medina County. Showers will
continue to drift north.

Original discussion...
majority of the thunderstorms are diurnally driven/enhanced and
expect US to be at the peak of areal coverage through the late
afternoon/early evening hours. Steering flow is weak and for the
most part storms are affecting their own movement. Heavy rainfall
is the primary threat...with an inch or two very likely for those
lucky/unlucky enough to be targeted by a storm. Traditional severe
storms not expected (high wind,large hail) with little support for
that. There is a bit of jet energy overhead tonight and do not
think storm chances will diminish to zero. Will continue the
scattered shower/thunderstorm mention through the night. Somewhat
milder tonight and muggy...mid/upper 60s for lows.

&&

Short term /Saturday night through Monday night/...
this whole system is slow to shift out of here and in fact have
drawn out the precip chances into Monday across the eastern half
of the area. Local trough across the Great Lakes trapped south
of a southern Canadian ridge. There is nothing upstream to kick it
out. We should have decent coverage of storms on Saturday too
especially north and east...again diurnally enhanced. Sunday/Monday
the upper trough slowly lifts out and the surface stationary front
washes out in place. High pressure attempts to build in from the
western lakes to Northwest Ohio. But with a bit of cyclonic flow
lingering across eastern Ohio/NW PA had to pull 20 percent precip
chances into Monday. Temperatures through the entire period will
be seasonable.

&&

Long term /Tuesday through Friday/...
extended forecast will be dominated by another thermal ridge
building in from the west. The models are in fairly good agreement
with the strength of the ridge and the amount of heat that will nose
into the region. The warm air advection will kick in Tuesday which
will likely keep convective out of the area through Thursday as the
air mass may get capped off under the building ridge. The ridge
breaks down by next Friday with a short wave passing by to the north
Friday into Friday night. This will likely bring a front into the
area with our best chance for convective activity.

&&

Aviation /18z Friday through Wednesday/...
main concern for initial periods of the taf are the locations of
the hit/miss thunderstorms that are developing in this unorganized
environment. The Lake Shadow area was expected to hold storms away
from cle yet the boundary has stalled just over the Airport. We
be going with the more pessimistic forecast for cle given the
lack of that stronger lake breeze. Eri however should remain VFR.
The rest of the taf sites will see the potential for thunder, but
isolated chances. Have tempos for tol/fdy/mfd for later this
afternoon when an area of low pressure moves in from the west and
adds support for convection. Any thunderstorms that develop today
will be slow moving and could produce heavy rainfall. Storm
coverage should lessen overnight with the reduced instability.
Have no mention at this time of rain overnight. The moist airmass
will linger so expect MVFR visibilities.

Outlook...non-VFR possible in sct thunderstorms Saturday and Sunday.
Areas of morning fog possible each morning.

&&

Marine...
a diffuse cold front lingers just south of the lake with a series of
weak lows moving across it tonight into Saturday night. Some models
hint at a slight increase in the northeast winds tonight to around
15kt as the first low tightens the pressure gradient slightly. Don't
feel this would last long enough to have a notable impact on the
wave heights as the gradient relaxes a few hours later. The same is
possible again Saturday afternoon with the second low. Overall
looking at an east/northeast wind around 10knots over the next
24hrs. High pressure will be slow to move in on Monday, but become
entrenched by Tuesday as an upper level ridge builds in.

&&

Cle watches/warnings/advisories...
Ohio...none.
PA...none.
Marine...none.

&&

$$
Synopsis...oudeman
near term...djb/oudeman
short term...oudeman
long term...Jamison
aviation...Jamison
marine...Jamison

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