224
FXUS61 KBUF 222315
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
715 PM EDT Fri Aug 22 2025

.SYNOPSIS...
High pressure will slide off to our east tonight and Saturday. This
will result in warmer temperatures through the first half of the
weekend...along with fair dry weather through most of Saturday. A
cold front will then slowly cross our region Saturday night and
Sunday while bringing showers and scattered thunderstorms. A much
cooler airmass following in the wake of the front will then bring
unsettled conditions and below normal temperatures for the first
half of next week.

&&

.NEAR TERM /THROUGH SATURDAY/...
Surface high pressure draped across our region will provide us with
pleasant late summer weather for the rest of this evening.

Tonight the surface ridge will slide east and out across New
England...while upper-level ridging briefly builds across our area
out ahead of a deepening upper level trough/associated surface low
over Ontario Province. This will maintain dry and tranquil weather
across our region...with some patchy fog again possible within the
Southern Tier valleys and east of Lake Ontario as we push through
the second half of the night...though areal coverage should be more
limited than what was seen last night. Otherwise it will be another
comfortable night...with lows ranging from the lower-mid 50s across
the interior of the Southern Tier/North Country to the upper
50s/lower 60s elsewhere.

On Saturday the increasingly vertically stacked low over Ontario
Province will slowly make its way to James Bay...with its trailing
cold front slowly pushing across the central Great Lakes. Well out
ahead of this...an increasing southerly return flow of warmer and
somewhat more moist air will reside across our region...and will
result in warmer highs mostly in the lower to mid 80s...along with
surface dewpoints climbing to moderately humid levels in the lower
to mid 60s.

While dry weather should continue to prevail through at least the
early to mid afternoon hours of Saturday...this may change to a
limited extent during the later portions of the afternoon...as a
weak surface trough sets up from interior portions of the Southern
Tier northeastward across the Finger Lakes and into north-central
New York. In the presence of our warming/moistening airmass...which
will allow for the development of weak to modest instability...the
modest low level convergence along this feature may be just enough
to pop a few isolated to widely scattered showers and storms...with
any such activity then tracking north-northeastward in the vicinity
of this boundary through early Saturday evening.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/...
Saturday night and Sunday the broad...vertically-stacked low will
slowly meander around the southern portion of James Bay...while
slowly pivoting its trailing cold front and leading prefrontal
trough eastward and across our region between Saturday night and
Sunday evening. These features will lift our warm and moderately
humid airmass...and thus should generate a couple rounds of
scattered to numerous showers and thunderstorms in the process.
Latest multimodel consensus still suggests that the coverage of
these will peak across far western New York Saturday night...and
across our eastern zones between later Saturday night and
Sunday...for which a range of likely to lower-end categorical (60-
80%) PoPs remain in play.

Given the presence of 35-45 knots of deep-layer environmental
shear...there remains some concern for the development of at least a
couple strong to severe storms across our far eastern zones Sunday
afternoon...with this potential ultimately contingent on the amount
of instability that is realized. The latter will in turn be
dependent upon both the forward speed of the front and the extent of
any clouds/pcpn preceding it...with the wavy and slow-moving nature
of the front *potentially* allowing for the development of greater
amounts of instability...as advertised by some of the shorter-term
guidance.

General subsidence in the wake of the front and dry slotting aloft
should then bring about a diminishing trend to any showers/storms
across our far eastern zones Sunday night...with a few lake effect
showers becoming possible downwind of the lakes overnight as
progressively cooler air works in aloft. Speaking of which...the
latter will also allow overnight lows to drop back to the mid to
upper 50s in most areas...with some lower 50s across the higher
terrain of the Southern Tier/North Country.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
Anomalously deep...full-latitude upper level troughing will
consolidate its grip across eastern North America on Monday as
another vigorous shortwave rounds its base...then will remain in
place through Tuesday night...before gradually weakening and
broadening later Wednesday into Thursday. This feature will deliver
a shot of the coolest air we`ve seen in a while (850 mb temps
falling into the middle single digits above zero) Tuesday and
Wednesday. This will not only result in temperatures falling to
solidly below normal levels during the first half of next week...but
will also translate into unsettled conditions through at least
Tuesday night...with some lake effect rain showers downwind of the
lakes each night/morning...and more general diurnally-driven
scattered showers and isolated thunderstorms following each
afternoon/early evening.

With blended guidance still unable to adequately resolve the lake
effect shower potential this far out in advance...have again
inserted some higher PoPs downwind of the lakes to account for this
Monday night/Tuesday morning (50% chance) and again Tuesday night/
Wednesday (30%-20% chances respectively). By later Wednesday...
increasing low-level ridging and the onset of gradual warming aloft
should bring about a trend back toward drier weather...with dry
weather and highs largely back in the 70s expected on Thursday.
Beyond that...another weak cold front could bring a renewed chance
of showers/storms Thursday night/Friday...with temps otherwise
running similar to those of Thursday.

&&

.AVIATION /23Z FRIDAY THROUGH WEDNESDAY/...
High pressure across our region will drift out across New England
tonight before drifting further into the western Atlantic on
Saturday. This will maintain fair dry weather and largely VFR
conditions through at least the first half of Saturday afternoon.
However,some patchy fog and associated reductions will be possible
within the Southern Tier valleys and east of Lake Ontario later
tonight.

Later Saturday afternoon and early Saturday evening, a few isolated
showers and storms and associated brief/localized restrictions will
become possible along a developing weak surface trough draped from
the Southern Tier northeastward across the Finger Lakes and into the
North Country, with dry VFR weather otherwise continuing to prevail.

Outlook...

Saturday night and Sunday...VFR/MVFR with scattered to numerous
showers and a few thunderstorms.

Monday and Tuesday...Mainly VFR with a chance of showers and
embedded thunder afternoons/early evenings. MVFR in lake effect rain
showers overnights into the mornings downwind of the Lakes.

Wednesday...Mainly VFR with diminishing lake effect rain showers
downwind of the lakes.

&&

.MARINE...
Surface high pressure draped across the Lower Great Lakes will drift
eastward to New England tonight...then out into the western Atlantic
Saturday. Generally weak flow underneath the high will become light
to modest southerly tonight as the high drifts east...then will
increase a bit further out of the southwest Saturday and Saturday
night out ahead of an approaching cold front. At this point
conditions appear to largely remain below advisory criteria...though
could come close to advisory levels across far northeastern portions
of Lake Ontario Saturday night.

In the wake of the cold frontal passage Sunday and Sunday evening...
a much cooler airmass will overspread the Lower Great Lakes from
Sunday night on through the middle of next week. The resulting
increasingly unstable over-lake environment will allow for more
efficient downward transport of higher momentum air from aloft down
to the lake surfaces...and should lead to a better likelihood of
advisory-worthy conditions during this time frame.

&&

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

&&

$$

SYNOPSIS...JJR
NEAR TERM...EAJ/JJR
SHORT TERM...JJR
LONG TERM...JJR
AVIATION...EAJ/JJR
MARINE...JJR