Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Cleveland Ohio
415 am EST Monday Nov 30 2015
high pressure over the New England states will drift southeastward
off the New England coast this afternoon. Low pressure will
develop over the Central Plains and strengthen as it moves into
the western Great Lakes by Tuesday night. An occluded front is
expected to sweep across the region Tuesday afternoon and
evening. On Wednesday a trough of low pressure will slide across
Near term /until 6 PM this evening/...
low level cloud cover will not exist for most locations through
the day as easterly downsloping flow strengthens. A warm front
will develop over southern Ohio today and begin to drift northward
with clouds increasing from the south through the afternoon. At
this point it appears that the easterly downsloping flow will be
enough to delay the onset of any light rainfall until after
sunset. However it may get close enough to warrant a slight chance
mention across the south for late this afternoon.
Downsloping flow and at least a few hours of sunshine should allow
highs to warm above seasonal averages. Locations with the best
downsloping flow will attempt to warm into the lower 50s. Elsewhere
highs will be in the middle to upper 40s.
Short term /6 PM this evening through Thursday night/...
the warm front will lift across the region overnight with rain
spreading northward. Best chances will not arrive until after
midnight and should reach likely levels by sunrise. Rain chances
will increase a bit more on Tuesday as the occluded boundary
arrives and sweeps across the region through the afternoon and
evening. Highest probability of precipitation should be across the eastern half of the
region with the frontal boundary. By late evening all the showers
should be east of the County Warning Area. We will then remain
dry through the night but an upper level trough will be
approaching Northwest Ohio Wednesday morning. As this trough sweeps
across Northern Ohio and northwest PA it will allow colder air to surge
eastward. So any precipitation in the wake of the trough will
transition to some snow. Although it may remain just warm enough
to keep it a mix for much of the area. However the higher terrain
of NE Ohio and northwest PA will see better chances of seeing all snow by
Thursday morning. The lake effect setup looks favorable for a very
short period after midnight Wednesday night through Thursday
morning. Any accumulations look light at this point in time and
should be no more than an inch or 2. High pressure will begin to
ridge northward from the Ohio River valley Thursday night.
Tuesday will be a warm day ahead of the frontal boundary with
highs well into the 50s. Cooler Wednesday and Thursday with highs
not all that far from seasonal averages.
Long term /Friday through Sunday/...
a dry and relatively mild period coming up for this weekend as
the ridge builds overhead. One backdoor cold front may get into northwest
PA/far NE Ohio and bring the winds around off of the lake Friday.
Little moisture and practically no precipitation associated with this
front as it looks now...therefore will have a dry forecast through
the weekend. Seasonable lows expected with high pressure overhead
and mostly clear skies. Daytime highs will right around 50.
Aviation /06z Monday through Friday/...
NE flow off of Lake Erie has pushed some MVFR strato cumulus into Northwest
Ohio. Low ceilings at ktol should break up as the flow becomes east
overnight. Elsewhere just expecting some high clouds overnight
with middle level ceilings spreading from SW to NE across the area on
Monday. Some warm air advection showers are possible in the south
late in the taf period. Will bring in some lower clouds Monday
evening as well. Ceilings should dip to MVFR after the taf period
ends. East to NE flow under 10 knots will continue.
Outlook...non VFR should develop south to north Monday night then
tend to prevail much of the time into Wednesday night before shifting
into mainly the snowbelt for Thursday.
persistent east flow today with high pressure centered across New
England will continue to make things somewhat choppy near the islands.
As a front lifts north toward the lake early Tuesday morning winds
will come around to the southeast and then south by late Tuesday
morning. The low will linger across the Central Lakes and slowly
weaken and fill as it shifts across the eastern lakes. Towards
Wednesday morning winds are expected to increase some and shift
more from the west-southwest...and finally the northwest as the
trough/whats left of the low passes. Beyond this though high pressure
will take over and be centered just south of the lake by Friday.