Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Cleveland Ohio
348 am EDT Tuesday Oct 13 2015
a cold front will move east of the area early this morning followed
by a second reinforcing cold front this afternoon. High pressure
will move across the upper Ohio Valley late Wednesday then move
off the southeast coast Thursday. This will allow another cold
front to push across the forecast area Thursday night.
Near term /until 6 PM this evening/...
cold front just east of a Cleveland to Montana Vernon line...and will
move east of the forecast area by daybreak. To the west clear
skies behind the front in the dry slot will gradually give way to
overcast skies as secondary cold front approaches from the
northwest. Secondary cold front expected to move east of forecast
area by early afternoon. The 850 mb temperatures dip to 4c...which is
cold enough support lake effect showers. With a west flow best
chance of showers northern portion of the primary snowbelt
Short term /6 PM this evening through Friday night/...
little change in the short term forecast. Both the GFS and European model (ecmwf)
continue to move high pressure across the upper Ohio Valley late
Wednesday and then off the southeast coast Thursday. This allows
next cold front to push across the forecast area Thursday night.
Models continue to be in good agreement with the timing of the front
so bumped probability of precipitation up to likely on Thursday night. By Friday afternoon
another potential for More Lake effect showers as the 850mb temperatures
plunge to -2c. Luckily thickness still support rain...for now.
Long term /Saturday through Monday/...
cold front is well past the region on Saturday with lake effect
clouds and showers anticipated across NE Ohio into northwest PA. Models
have trended cooler than last nights runs which will require US to
mention the word snow in the forecast. The chances of snow will be
Saturday night into Sunday for the higher terrain of northwest PA. At this
point it appears accumulations on the ground are unlikely but a
light dusting on a car or the roof of your home may occur. Southerly
winds will return on Monday with warmer temperatures.
It will be much cooler than average for much of the long term
period. Highs on Saturday will generally be in the 40s...although a
few locations where some sunshine will occur may top out around 50.
As skies clear over a larger area of Ohio by Saturday evening it
looks as if we are setting the stage for a widespread frost and
possibly a hard freeze for several locations. More details to come
through the week but make plans now to protect anything that is
sensitive to these colder temperatures. Slightly warmer on Sunday
with many locations within a couple degrees of 50. Southerly winds
on Monday will allow highs to return to the middle 50s to round 60.
Aviation /06z Tuesday through Saturday/...
area of light rain continues to move across eastern Ohio into northwest
PA. Expect VFR with the showers until they clear northwest PA by 08z. The
middle and high level cloud cover will pivot slowly eastward
through the night with at least some brief clearing at most
locations for a few hours. There may be an area of clouds that
drift from west to east through middle morning. Ceilings could
briefly become broken as they pass but will remain VFR. The main
surge of moisture that will then keep the region overcast arrives
by late morning west and into the afternoon for points east. As
the cooler air arrives during the evening ceilings may dip to
around 3500 feet...especially where winds are off of Lake Erie.
Winds of 10 to 15 knots will gradually shift around to the west
through the remainder of the night. The westerly winds will
continue into this afternoon and become gusty. Gusts up to 20
knots will be common but could be in the 25 to 30 knot range near
Outlook...non-VFR possible mainly NE Ohio and northwest PA Wednesday through Sat.
first surge of cooler air has crossed half of Lake Erie as of 07z
and will pass east of the lake by 12z. This will provide west winds
to all of Lake Erie by 12z. Winds of around 20 knots have already
been occurring across the western half of the lake. Since we are
already so close to small craft conditions across the western basin
we have gone ahead and expanded the advisory. Believe winds will
decrease enough across the west for the small craft to expire around
10 PM. East of the islands to Ripley the northwesterly winds will
keep small craft conditions going into at least Wednesday morning.
Still concerned it will need to be extended longer on Wednesday with
the longer fetch but will let later shifts take a closer look. Winds
will decrease Wednesday night but it will be brief as southwesterly
winds increase ahead of the next cold front. This front will likely
Cross Lake Erie by sunrise Friday morning. A Small Craft Advisory
may be needed ahead of the front across the east half of the lake
and will be a definite in the wake of the front for Friday into at
Marine...Small Craft Advisory until 10 am EDT Wednesday for lez145>149.
Small Craft Advisory until 11 PM EDT this evening for