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fxus61 kcle 230010 
afdcle

Area forecast discussion
National Weather Service Cleveland Ohio
810 PM EDT sun Sep 22 2019

Synopsis...
a cold front will push east across the region late tonight
through Monday. High pressure will build across the region
Monday night through Wednesday before another cold front moves
across the area Wednesday night into Thursday. High pressure
will quickly build east across the region Thursday night through
Friday.

&&

Near term /through Monday night/...
forecast remains on track for tonight with scattered showers
arriving in Northwest Ohio closer to midnight and sweeping east
across the area into Monday morning. Only concern for the
forecast overnight is the degree of cooling given breezy
southerly flow continuing and increasing cloud cover. Raised
minimum temperatures by a couple degrees across portions of Northwest
Ohio and closer to the Lakeshore.

Previous discussion...a cold front will approach the area
tonight, crossing the forecast area early Monday morning. A
surge of moisture with a fairly potent 50-60 kt low level jet
ahead of the front will bring scattered showers and perhaps a
few rumbles of thunder. The high res guidances has been trending
more scattered with the precip, which should enter the forecast
area from the west generally around and after midnight. The
initial precipitation forced by the low level jet and leading
mid level energy may be followed by a relatively dry period,
with this initial forcing well ahead of the surface boundary. By
the time the surface front moves into the area around 12z, a
diurnal minimum in precip coverage warrants only low likely/high
chance pops with the frontal passage. Have generally slowed
down the timing of pops progressing through the area relative to
the previous forecast. Highs will be more seasonable tomorrow
with low to mid 70s expected.

The surface front will clear the area to the east late Monday
afternoon, with drier conditions filtering into the area. Pops
will increase again Monday evening into the overnight hours
across far NE Ohio and northwest PA as a secondary mid level trough and
area of low level moisture swing southeast across the eastern
Great Lakes.

&&

Short term /Tuesday through Wednesday night/...
we have weak upper level ridging over the region on Tuesday as
an upper level low moves eastward across northern New England
region. An area of high pressure will be moving west to east
across the Ohio River valley. Tuesday actually looks like a
"normal" late September day with a few fair weather clouds and
seasonable temperatures. Southerly winds will return Tuesday
night into Wednesday on back side of the surface high pressure
which will be moving off the mid- Atlantic coast. A broad upper
level trough will be developing and building down across the
upper Midwest and Great Lakes region on Wednesday. Southwesterly
winds will increase 15 to 20 mph ahead of a an advancing cold
front Wednesday afternoon. We will add a few degrees to the high
temperature guidance and likely reach at least the lower to
middle 80s Wednesday afternoon. A few showers and isolated
thunderstorms may be possible Wednesday night into early
Thursday morning with the frontal passage. Slightly cooler
weather will follow on Thursday with skies clearing from west to
east as high pressure builds in from the west.

&&

Long term /Thursday through Sunday/...
the fast pace weather pattern will continue for the end of the week
with a mostly zonal flow shifting to a broad southwesterly flow for
the end of the week. A small and brief area of high pressure will
move over the region Thursday evening and move eastward. Southerly
winds will increase again by Friday and Friday afternoon. We added a
few degrees to guidance for Friday afternoon with another warm and
breezy day expected. There are some slight timing differences with
front Friday night or Saturday. The GFS is faster than the Euro. At
this time, we will mention scattered showers and storms possible by
next weekend with the next front and above average temperatures will
continue.

&&

Aviation /00z Monday through Friday/...
VFR conditions remain across the area this evening. Showers are
expected to move in from the west towards 04z then sweep east
across the area ahead of a cold front through approximately 18z.
Chances of thunder are low overnight but can not completely
rule out an isolated thunderstorm. Some MVFR visibilities are
possible in showers with ceilings also declining to MVFR as rain
moistens the low levels. Ceilings will tend to improve from northwest
to southeast between 15-20z.

Winds will be the other consideration overnight. Southerly gusts
have dropped off at most terminals since sunset but are
expected to re-develop overnight as the gradient increases
ahead of the front. A 40 knot low level jet is also expected to
develop and slide east across the area overnight and have
included a mention of low level wind shear at cak/yng where surface winds will
be lighter. This may need to be expanded to other terminals if
winds do not increase. Winds will shift to the west behind the
front on Monday and remain breezy.

Outlook...non-VFR possible in showers with a low chance of
thunderstorms Wednesday evening into Thursday morning.

&&

Marine...
the pressure gradient will continue to increase tonight with
southwest increasing 20 to 25 knots over the Lake. A frontal passage
will move through Monday morning with a shift to the west 15 to 20
knots and high waves expected near the Lakeshore Monday into Monday
night. The current Small Craft Advisory looks good at this time.
Winds and waves will relax by Tuesday with high pressure moving
across the region. South to southwest winds will increase again
ahead of the next cold front late Tuesday night into Wednesday with
winds 15 to 20 knots. Another high pressure system will briefly
build in on Thursday followed by a return to gusty southwest winds
on Friday.

&&

Cle watches/warnings/advisories...
Ohio...none.
PA...none.
Marine...Small Craft Advisory from 2 am Monday to 10 am EDT Tuesday for
lez145>149.
Small Craft Advisory from 2 am Monday to 4 am EDT Tuesday for
lez142>144.

&&

$$
Synopsis...greenawalt
near term...kec/greenawalt

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