Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Cleveland Ohio
656 PM EST Wednesday Nov 25 2015
a slow moving cold front will move east across the area
Friday into Friday night. High pressure will spread over Lake Erie
by late Saturday then stall into Monday before shifting off to the
northeast. Low pressure is expected to move across the lakes Tuesday
Near term /until 6 am Thursday morning/...
a few showers have developed where the low level jet was
increasing across Northwest Indiana. These showers should move
northeastward into Michigan. However they will be close enough to
Toledo to need a slight chance mention for after midnight.
Otherwise a thin layer of cirrus will continue to drift across the
region through the evening. Some thicker clouds will move into
the region after midnight. Only made minor changes to sky cover
and hourly temperatures.
rain from the front in the Midwest will try and spread close to
tol by the end of the night. Latest model runs have increased
lower level moisture by 12z and allowed measurable rain to spread
a little further southeast...thus now catching a few of our northwest co's.
With moisture at all levels increasing expect increasing clouds west
to east during the night. The added clouds and increasing south
winds will help to keep lows warmer than previous nights with
readings mostly only dropping into the low to middle 40s although
some inland spots in the east could see upper 30s.
Short term /6 am Thursday morning through Saturday night/...
relative humidity in the lower levels appears to stay low enough to keep most
rain at Bay until late Thursday night. However...with general lift
being induced by the low level jet and good moisture...can't rule
out a few light rain showers/sprinkles occurring in the northwest third of the
County Warning Area Thursday and early Thursday night so will increase the probability of precipitation a little.
Temperatures will stay above normal.
By late Thursday night...the slow moving cold front should finally get
close enough for some rain showers to have a better chance to push into the northwest
by the end of the night. Friday into Friday night...the cold front will
slowly move across the County Warning Area with rain showers looking almost definite. The
airmass does not appear very unstable but the dynamics could still
be strong enough for some isolated thunder.
With the main upper trough remaining well west of the area...the
front will stall over Kentucky into the Virginia's on Sat. Not convinced
that enough dry air will get pushed south over the area to end the
threat for rain all the way south through our southern counties so will
leave a small chance in the far south later Sat and Sat night.
Temperatures behind the front will be cooler for Friday night and Sat with
lows falling back into the 30s and highs on Sat more seasonal mainly
in the low to middle 40s.
Long term /Sunday through Wednesday/...
the overall pattern for early next week will feature a deep upper
low that had been nearly stationary across the western U.S. To
eject out into the plains by Tuesday. Of course the details with
this...including the track of a surface low and timing will have
influences on the forecast. With this pattern will lean toward the
ensemble guidance for a solution...which is also in line with wpc.
This will bring surface high pressure across the lower Great Lakes
for Sunday into Monday. Temperatures will be seasonable and
precipitation should be held south of the area. Monday night
clouds will increase and a surface low will track somewhere in the
vicinity of Illinois/in/western Kentucky and then toward the central Great
Lakes. With this path expect milder temperatures for Tuesday with
a cool down Wednesday as the cold front passes. For now precipitation
chances are focused on Monday night through Tuesday...lingering
into Wednesday across NE Ohio/northwest PA.
Aviation /00z Thursday through Monday/...
clouds will start to lower in Northwest Ohio overnight with a chance
of showers at tol after about 10z. These showers are mostly expected
to pass to their north where the low level jet is focused but
held onto a window into Thursday morning where showers will be in
the vicinity. Did not include low level wind sheer at tol or fdy
but it will be close. Southerly winds will increase overnight with breezy
conditions starting late tonight at all sites but cak/yng where
there will be fewer gusts. Winds will come up faster at eri due to
the downsloping component.
Outlook...non VFR likely to develop Friday in rain showers then improve Sat.
Increasing chances of non VFR by Monday.
light southerly winds will increase tonight to 15 to 20
knots /20 to 25 knots east/. Therefore have issued a Small Craft
Advisory for Geneva eastward through Thursday morning. South-
southwest winds will then continue at 15 to 20 knots through
Thursday and into Friday...likely making the offshore waters choppy.
A cold front approaches for Friday...with the frontal passage timing
somewhere between Friday afternoon and evening. There will be a wind
shift to the north behind the front Friday night and a brief pick up
in wind speeds. A small craft advection may be needed. By Sunday high
pressure settles over the lake and winds/waves will begin to
subside. Light easterly winds will develop Monday as the high stays
to our north and low pressure begins to develop across the middle
Mississippi River valley.
Marine...Small Craft Advisory from 10 PM this evening to 10 am EST
Thursday for lez148-149.