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050
FXUS61 KBUF 161808
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
208 PM EDT Thu May 16 2024

.SYNOPSIS...
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A few slow moving showers east of Lake Ontario into the early
evening hours, otherwise our region will remain dry with above
normal temperatures through today and tonight. A poorly organized
cold front will bring more coverage area to showers for the eastern
Great Lakes region tomorrow and tomorrow night, with a few rumbles
of thunder also possible. Showers may linger across southern
portions of the region Saturday before drier air builds in from the
north and returns partly sunny skies.
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&&

.NEAR TERM /THROUGH FRIDAY NIGHT/...
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An area of low pressure continues to swirl south of Long Island this
afternoon, with visible satellite imagery displaying clouds in
general light east to west flow on the periphery of this low over
our region. Our region will remain partly to mostly cloudy through
the afternoon hours.

Instability is quite weak this afternoon and early evening, with
just a few hundred J/KG of MUCAPE, and low level lapse rates around
6.5 to 7.0 C/KM. With a capping inversion around 600 hPa east of
Lake Ontario any showers that form in this light flow will be slow
moving, but likely not to grow too tall. Will have just a chance for
showers in the forecast.

Any diurnal convective showers will quickly diminish this evening.
Light flow with weak ridging in the lower levels. Dewpoints a just a
touch lower tonight, and with minimal to no rainfall today fog
coverage should be less than in recent nights. Will have some fog in
the river valleys of the Southern Tier and Black River Valley.

The next system will be approaching our region later tonight. Winds
will veer to southeasterly through the night. Just a 20 knot LLJ so
downslope wind gusts will be minor. While the cold front with this
next system is ill defined at times, looking in the mid levels a
distinct 700/500 hPa shortwave trough will carry northeastward from
the Ohio Valley. Increase in moisture and lift ahead of this
shortwave will bring rain showers to our doorsteps tomorrow morning.

As this shortwave passes across our region tomorrow a band of
showers and embedded thunder will move from west to east across our
region. Better instability remains across WNY, but better lapse
rates quickly move towards the east. Will carry a chance for
thunderstorms, with likely convection across WNY tomorrow moving
into the eastern Lake Ontario region tomorrow evening. As daytime
instability wanes, the threat for thunder will also diminish, though
lingering troughiness aloft will maintain chances for showers
through the entire night.

Lows tomorrow night will be a few degrees higher than tonight...due
to the southerly flow firmly entrenched for our region, and
lingering cloudiness. Highs on Friday will remain above normal in
the low to mid 70s.
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&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...

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High pressure takes over Saturday night providing generally quite
weather through the remainder of the this period. However...there
still will be a slight chance (20% or less) of a shower across the
Southern Tier Sunday afternoon. This is due to the influence of a
passing shortwave to our south. Highs on Sunday will be mild with
temperatures in the 70s.
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&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
High pressure will provide dry weather through at least
Tuesday. After that...chances for showers and storms increase as
a shortwave trough nears the region by mid-week.

Temperatures will also steadily increase to above normal ahead of
this trough through Wednesday.

&&

.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
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For the 18Z TAFS a deck of MVFR and low end VFR ceiling heights are
found. There are some breaks, but these clouds will remain into the
evening hours. A few showers east of Lake Ontario, otherwise we
should remain dry through 12Z.

Dewpoints are a tad lower tonight, and even though light flow, fog
should not be as widespread as the previous night or two. Will have
a little valley fog, that may near KJHW...otherwise mainly VFR
tonight.

Tomorrow a weak cold front, and mid level shortwave will near the
region. MVFR ceiling heights in the Southern Tier tomorrow morning
will spread north and eastward through the day across WNY. Showers
will near KJHW/KBUF and KIAG between 15Z and 18Z...slowly working
their way eastward through the day. Weak flow aloft will keep wind
gusts to a minimum.

Outlook...

Friday night...A chance for showers, with patches of fog around.

Saturday...Areas of MVFR with a chance for showers.

Sunday through Tuesday...Mainly VFR. An isolated shower Tuesday on
Lake Erie lake breeze.
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&&

.MARINE...
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A weak pressure gradient will continue general light winds
through the remainder of the work week. A mainly offshore,
southeast, flow will develop tonight and increase a little on
Friday as a weak cold front crosses the Lake. Following the
passage of the weak cold front winds are not expected to
increase much, and in fact remain light through Tuesday morning.
The next system of note will be a cold front Wednesday, one that
has a bit more structure, and a deeper surface low...with the
increasing pressure gradient likely to bring a bit more wind
and waves to the Lakes.
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&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...None.
MARINE...None.

&&

$$

SYNOPSIS...Thomas
NEAR TERM...Thomas
SHORT TERM...AR
LONG TERM...AR
AVIATION...Thomas
MARINE...Thomas