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883
FXUS61 KBUF 120543
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
143 AM EDT Wed Jun 12 2024

.SYNOPSIS...
Notably warmer weather is on the horizon...as temperatures will
climb back towards normal on Wednesday...then will reach well above
normal on Thursday. While a cold front will put the brakes on our
warm up for Friday and Saturday...mid summer warmth is guaranteed
for early next week.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
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Weak high pressure will supply fair dry weather for the region
overnight. Satellite imagery indicates the stubborn deck of stratus
from the Genesee Valley eastward is very slowly eroding and
shrinking, though high clouds associated with a weak shortwave over
Michigan are filtering in back across the west. Still, this partial
clearing will lead to some localized fog as we move through the wee
morning hours, especially down in the Southern Tier valleys.

The mid level disturbance will cross our forecast area on Wednesday.
While this push through with fairly abundant mid level clouds, it`s
not out of the question that a few spots could pick up a brief
shower or sprinkle. Otherwise it will be milder day with
temperatures FINALLY returning to the 70s.
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&&

.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
On Thursday our area will be situated within the deepening
southwesterly flow in between high pressure anchored off the east
coast...and a mid-level trough/associated area of low pressure
sliding across the Upper Lakes and central Ontario Province to
western Quebec. While the cold front associated with this system
will remain well to our west through the day...a weak leading
shortwave impulse and warm frontal segment out ahead of this system
will slide across our region. This may bring some widely scattered
showers/isolated thunderstorms during the afternoon...with the
greatest chances of these found across the counties bordering Lake
Ontario where the best combination of moisture...lift...and
instability will come into play. Outside of these the day will just
be dry...notably warmer...and increasingly breezy as the
southwesterly flow across our region ramps up. Highs will mostly
range in the lower to mid 80s...with the warmest readings (upper
80s) found near Dansville...and the coolest temps immediately
northeast of Lake Erie due to the stiffening southwesterly breeze
off that lake...which may gust to 30-35 mph at times.

Thursday night and very early Friday the core of the mid-level
trough and the attendant surface low will eject northeastward across
Quebec Province...while pivoting its trailing cold front across our
region. In the spatial and temporal senses the best overall chances
for any associated showers and embedded storms will lie near Lake
Ontario and across the North Country Thursday evening...with this
potential then fading through the rest of the night and with
increasing southeastward extent as instability wanes and the frontal
boundary becomes increasingly estranged from its departing mid-level
support. Otherwise...lows will largely be in the lower to mid 60s.

On Friday the main cold front will slide off to our southeast...
with high pressure and drier air building eastward into our region
in its wake. With the guidance continuing to trend toward the above
happening more quickly...any convection associated with the front
should be faster to exit our region during the morning...leaving
behind a largely dry afternoon. The one possible exception to this
will be across the North Country and Saint Lawrence Valley...where
the approach and passage of a secondary shortwave trough/weak cold
front could produce a few more widely scattered showers and storms
during the afternoon and early evening. Otherwise the cooler and
drier airmass building in behind the front will result in highs
ranging through the 70s.

The increasingly expansive surface ridge will then strengthen as it
builds across our region Friday night...bringing an end to any
spotty convection across the North Country and leading to a quiet
and tranquil night otherwise. With good radiational cooling
conditions in place...lows will settle back into the upper 40s
across the North Country and interior of the Southern Tier...and
into the lower to mid 50s elsewhere.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
Upper level trough responsible for the cooler weather earlier this
week will exit the Northeast Saturday, while ridging will advance
and build east across the Great lakes Sunday through Tuesday. While
the ridge builds east across the region, a short wave trough will
ripple across the top of the ridge Monday.

Overall with the exiting trough followed by the ridge building east,
surface high pressure centered over the Great Lakes Saturday morning
will slide southeast towards the Atlantic Coast by Monday morning.
While this pattern will support dry weather throughout the weekend,
it will also support warm and moist Gulf of Mexico air to filter in
across the area supporting temperatures to surge above normal for
mid June.

The aforementioned shortwave trough rippling across the top of the
ridge across the Great Lakes, will support a surface low well to the
north across northern Ontario and Quebec. Extending southward from
the low will be a pair of fronts to slide east across the eastern
Great Lakes. This far out, timing and placement continues to be in
question and therefore have slight chance to low end chance for
showers and afternoon thunderstorms Monday afternoon through
Tuesday. Despite the frontal passages, temperatures will continue to
be above average.

&&

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
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Mainly VFR conditions across the region for the 06z TAF cycle as
surface high pressure slowly moves east of the Great Lakes.

Stubborn deck of low VFR/MVFR stratus from about KOLE to KSDC as of
06z will continue to slowly erode and shrink eastward through the
pre-dawn hours. This partial clearing will allow localized fog to
develop down in the Southern Tier, which is expected to impact KJHW
through about 12-13z.

Widespread VFR is expected from KROC westward through the day
Wednesday, with some lingering low VFR/MVFR cloud cover across the
Finger Lakes and North Country. These should then clear out by
Wednesday evening with mainly clear skies overnight.

Outlook...

Thursday...VFR.
Thursday night and Friday...VFR/MVFR. Showers and thunderstorms
likely.
Friday night through Sunday...VFR.
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&&

.MARINE...
High pressure will build across the Lower Great Lakes resulting in
light winds which will last through Wednesday night.

A cold front will then move across the Lower Great Lakes late
Thursday night and early Friday. Southwest winds will increase ahead
of the front Thursday, with winds remaining elevated through Friday.
This will bring choppy conditions to both lakes. High pressure will
then build back across the waters with light winds and generally
favorable boating conditions during the weekend.

&&

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

&&

$$

SYNOPSIS...RSH
NEAR TERM...PP/RSH
SHORT TERM...EAJ
LONG TERM...JJR
AVIATION...PP
MARINE...Apffel