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111
FXUS61 KBUF 010222
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
1022 PM EDT Sun Jun 30 2024

.SYNOPSIS...
Abundant clouds and scattered showers will linger through the first
half of the night before a clearing trend develops late tonight
through early Monday morning. High pressure will then build into the
Great Lakes Monday, then to New England Tuesday with a fantastic
start to the week. The next chance of showers and storms arrives
late Wednesday with the next cold front.

&&

.NEAR TERM /UNTIL 6 PM MONDAY EVENING/...
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Radar imagery showing light showers east and southeast of Lake
Ontario late this evening, supported by moist/cyclonic flow in the
wake of the departing low over the Canadian Maritimes, along with
contributions from upslope flow and lake instability. These showers
will gradually diminish overnight. Farther west, a few sprinkles and
very light showers persist across Western NY late this evening,
especially across the Genesee Valley and Finger Lakes. These too
will diminish overnight.

Satellite imagery showing abundant cloud cover over all of the
eastern Great Lakes late this evening, almost a fall looking
satellite loop. Clouds will persist past midnight before clearing
develops from northwest to southeast late. Lows will drop back into
the mid 50s in most areas, with some upper 40s in the cooler
locations of the Southern Tier and Lewis County.

High pressure over the Upper Great Lakes will make its way across
our region Monday during the afternoon and evening. Any lingering
upslope and lake effect clouds early will give way to clearing with
abundant sunshine for the afternoon. Highs will reach the low to mid
70s in most locations, upper 60s for higher terrain.

Little change Monday night with quiet, dry weather as high pressure
moves through the region. Lows will be found in the upper 40s in the
cooler locales to low to mid 50s elsewhere.
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&&

.SHORT TERM /6 PM MONDAY EVENING THROUGH WEDNESDAY NIGHT/...
A large expanse of surface high pressure underneath a stout mid-
level ridge will lie across central NY to open the period Tuesday.
Dry weather will persist through Tuesday night as the ridge slowly
shifts towards and away from the New England coast. The onset of
warm advection on the backside of the surface high will allow high
temperatures Tuesday in the upper 70s to low 80s. Dewpoints will
also rise a few degrees though should remain in comfortable
territory, generally averaging in the 50s. Deepening southerly flow
Tuesday night will lead to rather warm overnight low temperatures,
especially across the Lake Plains where temps will only dip into the
upper 60s.

Unsettled weather returns later Wednesday and into Wednesday night
as a robust mid-level trough and attendant surface low track from
northern Ontario to Quebec across Hudson Bay. This will initially
cause warm front to lift out of the Ohio Valley and into the
forecast area Wednesday morning, before the system`s cold front sags
southeast through the region Wednesday night. While the initial
frontal passage in the morning is expected to be dry, moisture
advection into the warm sector behind it will allow for increasing
chances for showers and thunderstorms later in the afternoon and
into the evening, particularly from the Genesee Valley westward. Mid-
range guidance indicates PWATs approaching 2" ahead of the cold
front Wednesday afternoon which could support some locally heavy
downpours, especially in the western Southern Tier where instability
is expected to be greater. Otherwise, it will be a rather sultry day
as the increasing moisture will also lead to muggier dewpoints
values in the mid to upper 60s, while high temps climb WELL into the
80s in most areas. The typical warm spots across the interior
valleys such as Dansville may even breach the 90 degree mark
Wednesday afternoon.

The cold front will make its way through the eastern Great Lakes
Wednesday night before it runs up against the strong offshore ridge,
causing it to stall out across Pennsylvania. Broad scale ascent
along a ribbon of deeper moisture will allow for a round of
widespread showers and a few storms just out ahead of the cold front
Wednesday night, mainly in the first half of the night. Weak surface
high pressure and subsidence drying should allow much of western NY
to begin drying out in the second half of the night, though lower-
end chances for showers will otherwise linger through the pre-dawn
hours as the front`s momentum slows over the region. Temperatures
Wednesday night will likely depend on the exact timing of the front,
though it is expected to be rather muggy with mid 60s to low 70s for
overnight lows.

&&

.LONG TERM /THURSDAY THROUGH SATURDAY/...
A secondary shortwave trough will round the base of the longwave
trough Thursday, pulling longwave pattern east across the lower
Great Lakes and New England Thursday night.The exiting shortwave
will support the cold front to finish sliding southeast across the
area Thursday, ushering in a cooler and less humid airmass into the
region. Thursday will take on a drying trend with just a few
scattered showers and thunderstorms heading into the afternoon.
Temperatures for the holiday will feature highs in the low to mid
80s.

As the longwave trough pull east across the lower Great Lakes and
New England Thursday night placing zonal flow across the area, the
now stalled cold front to the south of the area. While the area will
remain mostly dry, a few showers and thunderstorms can`t be ruled
out, especially along and near the New York/Pennsylvania state line.

Zonal flow Friday will give way to the next trough diving across the
Great Lakes through the weekend, it is this point the the forecast
the model guidance begins to diverge with the timing and positioning
of the next shortwave and corresponding cold front for Friday night
through Sunday. With this in mind, have chances for showers and
thunderstorms lasting throughout the weekend with the better chances
for the weekend being Saturday, but time will tell being this far
out.

&&

.AVIATION /03Z MONDAY THROUGH FRIDAY/...
Abundant stratocumulus will persist through the first half of the
night with a mix of lower end VFR and MVFR CIGS, with MVFR favored
across higher terrain and southeast of Lake Ontario. The clouds will
scatter out from northwest to southeast late tonight through Monday
morning.

High pressure will build into the Great Lakes Monday, with any
lingering clouds clearing, allowing for VFR to prevail the rest of
the day.

Outlook...

Tuesday...VFR.
Wednesday...VFR, then MVFR with showers and thunderstorms likely
late.
Thursday...Mainly VFR with a chance of a shower or thunderstorm
across the western Southern Tier.
Friday... Mainly VFR with a chance of a shower or thunderstorm.

&&

.MARINE...
Moderate to strong west to northwest winds behind the front are
producing small craft conditions on both lakes. Small craft
advisories continue into the evening on both lakes, with elevated
winds and waves lasting the longest along the south shore of Lake
Ontario.

Small Craft Advisory conditions will end by early Monday morning,
but north winds and residual wave action will produce very choppy
conditions on both Lake Erie and Lake Ontario through early
afternoon before improving later in the day.

Much more favorable boating conditions will return late Monday
through Tuesday as high pressure drifts across the eastern Great
Lakes.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
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NY...Beach Hazards Statement until 5 AM EDT Monday for NYZ002>006.
MARINE...Small Craft Advisory until 5 AM EDT Monday for LOZ042>044.
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&&

$$

SYNOPSIS...AR/Hitchcock
NEAR TERM...AR/Hitchcock
SHORT TERM...PP
LONG TERM...EAJ
AVIATION...Hitchcock
MARINE...AR/Hitchcock