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935
FXUS61 KBUF 021854
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
254 PM EDT Thu May 2 2024

.SYNOPSIS...
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Dry weather will continue through much of Friday as high pressure
builds across the western and northcentral NY through the evening,
before slowly sliding east into New England tonight. A warm front
will cross the region later tonight into the first half of Friday
bringing a surge of warmer air into the area boosting high
temperatures well above average to end the work week. A couple of
slow moving cold fronts will then cross the area Friday night
through Sunday bringing a couple more rounds of showers and possibly
a few rumbles of thunder. High pressure returns with mainly dry
weather for the start of the new work week.
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&&

.NEAR TERM /THROUGH FRIDAY/...
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Ridging will build in across western and central NY through this
evening providing plenty of sunshine for the bulk of the region,
however some extra low level clouds are found toward the North
Country and Saint Lawrence Valley as a weak shortwave dives
southeast across far northeastern NY and New England, but should
remain just far enough to our northeast to keep areas toward the
North Country dry. Expect highs mainly in the mid to upper 60s south
of Lake Ontario, with low 70s near the NY/PA line...and upper 50s to
low 60s east of Lake Ontario. Still a bit above average for early
May across areas south of Lake Ontario.

Surface high pressure slides east of the area, while upper level
ridge crests overhead Thursday night. These features will keep our
weather dry with overnight lows mainly ranging through the 40s, with
low 50s possible along the Lake Erie shore northwest of the
Chautauqua Ridge/Boston Hills owed to a weak southeasterly flow
developing on the back side of the high.

On Friday, surface high pressure settles toward the New England
coast, while upper level ridge axis slowly crosses the area.
Increasing low level southerly return flow will help push a surface
warm front northeastward across the region through the first half of
Friday. This will allow a surge of warmer to spread across the
region boosting highs into the mid and upper 70s for much of the
region, with some lower and even a few mid 80s across far western NY
and the traditional warmest spots in the Genesee Valley. Areas
downwind of the Lakes will be cooler.

High pressure will keep much of Friday dry, however as the upper
level ridge axis drifts east across eastern NY, the door will open
to a southwesterly flow of deeper moisture that will advect in
across at least far western NY by late in the day. A cold front
slowly approaching from the west will eventually interact with this
increasing moisture, and in combination with daytime heating may
produce a few scattered showers and storms as early as late Friday
afternoon across far western NY. Best focus would be along the lake
breeze boundary that will be found just inland of Lake Erie.
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&&

.SHORT TERM /FRIDAY NIGHT THROUGH SATURDAY NIGHT/...

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Friday night through Saturday night unsettled weather will return to
the region. The mid level trough upstream will drift east into the
eastern Great Lakes and then stall as the downstream pattern
stagnates in response to a closed low over the North Atlantic to the
east of New England. A plume of deep moisture will become situated
across the eastern Great Lakes, with numerous convectively augmented
vorticity maxima drifting through the mean southwest flow across the
region.

The combination of moisture and forcing will bring occasional rounds
of showers Friday night across Western NY, and then the entire
region Saturday through Saturday night. The best chance of thunder
will be on the front side of the system late Friday afternoon and
Friday night when instability is greatest. Cooler temperatures will
then restrict the thunder potential Saturday through Saturday night,
although there may still be a slight chance of a few spotty
thunderstorms if there are enough breaks in the rain and overcast.
The clouds and showers will keep highs in the mid 60s for lower
elevations and around 60 for higher terrain Saturday.
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&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
Sunday, the mid level trough axis stalled over the eastern Great
Lakes since Friday night will start to make some eastward progress,
and also weaken with time. Lingering weak forcing and moisture will
still support a few rounds of showers, with the greatest coverage
likely to be east of the Genesee Valley.

Surface high pressure and a bubble of drier air will then build into
the Great Lakes Sunday night and Monday, with a return to mainly dry
weather. Model guidance begins to diverge with the timing of the
next system by Tuesday, with the GFS faster in the return of
moisture and forcing while the ECMWF/GEM are slower. Given the
slower trend of the ECMWF/GEM, kept POPs on the lower end of the
chance range.

Rain chances will increase Tuesday night through Wednesday as low
pressure moves into the upper Midwest, with a downstream warm front
moving northeast across the Great Lakes region. Enough instability
may return to support at least a slight chance of thunder by the
middle of next week.

Temperatures will continue to run above average through the period,
with highs in the 60s Sunday and Monday giving way to 70s by Tuesday
and Wednesday.

&&

.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
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VFR conditions and generally light breezes expected for the
remainder of the day, with a few west to northwest gusts up to 15-20
knots across the terminals before winds relax as high pressure
builds over western and northcentral NY through this evening.

Other than some thickening mid and upper level decks later Friday
morning into the afternoon, high pressure remains in control tonight
through much of Friday with widespread VFR conditions and mainly
light winds expected to continue through the end of the TAF period.

Outlook...

Friday afternoon...Mainly VFR with a chance of showers and
thunderstorms across western NY late in the day.

Saturday...MVFR to VFR with showers likely and possible
thunderstorms.

Sunday...Morning showers, then a chance of afternoon showers,
otherwise mainly VFR.

Monday...VFR.

Tuesday...Mainly VFR. Chance of showers and thunderstorms.
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&&

.MARINE...
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Mainly weak pressure gradients are expected through the end of the
work week into this weekend across the lower Great Lakes supporting
winds to generally remain below 15 knots. Expect this to bring some
choppy waters at times, however conditions will remain below
headline criteria. While quiet weather continues for the end of the
work week, a few showers and thunderstorms will be possible
late Friday through Sunday.
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&&

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

&&

$$

SYNOPSIS...JM
NEAR TERM...JM
SHORT TERM...Hitchcock
LONG TERM...Hitchcock
AVIATION...JM
MARINE...JM