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159
FXUS61 KBUF 192346
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
746 PM EDT Mon May 19 2025

.SYNOPSIS...
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Cool, dry weather will continue across western and north-central
NY through Tuesday. Frost is likely across western NY,
especially interior, protected locations. Unsettled weather and
more unseasonably cool temperatures Wednesday through Saturday.
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&&

.NEAR TERM /THROUGH TUESDAY/...
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Satellite imagery shows clear skies across western NY and
into parts of central NY/Oswego county this evening. A shield of
low clouds persist across Jefferson, Lewis, and northern Oswego
counties. It is a decent set-up for radiational cooling across
much of the forecast area tonight. Low temperatures will fall into
the 30s, low 40s southeast of Lake Ontario. A Frost Advisory is
in effect across western NY including the Finger Lakes. Low
clouds and a northerly wind will persist east of Lake Ontario
tonight. While patchy frost is possible if clouds diminish,
confidence is low that it will be widespread. Also, locations
along the immediate shorelines of Lake Erie and Lake Ontario
will be a few degrees warmer and negate frost development.

Tuesday...after a chilly start high pressure will provide sun-filled
skies for much of the area. Overall...a beautiful day is expected
with highs in the upper 50s and 60s. Enjoy the sunshine...the rest
of the week does not look all that great, cool and showery
again.
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&&

.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/...
The brief few days of dry weather will come to an end late Tuesday
night through Wednesday. The narrow ridge axis surface and aloft
stretching from northwest Ontario to the eastern Great Lakes will
fade away by Wednesday. A mid level low over western Quebec will
interact with another closed low moving out of the upper Midwest,
with the system evolving into a deep/broad mid level closed low
over southeast Canada and the Great Lakes by Thursday. A surface low
on the southern flank of the mid level circulation will cross the
southern Great Lakes region Wednesday, then linger over the eastern
Great Lakes Wednesday night through Thursday night.

A wing of warm advection and strong moisture transport ahead of the
low will bring thickening clouds Tuesday night, with rain spreading
into the western Southern Tier late. The shield of rain will
continue to advance northeast across the rest of Western NY
Wednesday, reaching Central NY later in the day. The North Country
may stay dry for much of Wednesday before rain develops Wednesday
evening.

Wednesday night through Thursday night, persistent ascent within the
deepening mid level trough coupled with a persistent moisture feed
off the Atlantic will continue to bring periods of rain to the
entire region. Rainfall totals Wednesday through Thursday night may
reach 1.0" to 1.5" south of the NYS Thruway, with 0.75" to 1.0" near
the south shore of Lake Ontario, and less for the North Country.
This rain will be spread out over several days, with minimal risk of
flooding.

Temperatures will remain well below average through the period.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
A broad, deep, and slow moving mid level low will move from the
Great Lakes Friday to New England Saturday, then the Canadian
Maritimes Sunday. Cool, moist cyclonic flow will continue to support
frequent showers across the region Friday and likely into Saturday.
Showers will gradually diminish in coverage by Sunday, with some
early optimism for a return to mainly dry weather by Memorial Day
Monday as high pressure builds into the Great Lakes.

Temperatures will remain very cool Friday through Saturday, with
some improvement Sunday through Monday as the airmass modifies and
some sunshine returns.

&&

.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
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VFR conditions will continue through Tuesday as high pressure
resides over western and north-central NY.

Outlook...

Wednesday and Saturday...IFR to MVFR with showers.
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&&

.MARINE...
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Light to modest chop will be found on area lakes this evening.
High pressure wedging in over the region tonight which will
provide mainly light winds and wave action on Tuesday.

A low pressure system moving into the eastern Great Lakes from the
Ohio Valley Wednesday will then very slowly cross the lakes through
Friday. This will cause northeast winds to strengthen starting
Tuesday night. The greatest wave action is expected to remain mostly
offshore through Wednesday night, though SCA conditions could be
reached for a time along the southwestern shoreline of Lake Ontario.
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&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...Frost Advisory from 2 AM to 8 AM EDT Tuesday for NYZ001>003-
     010>014-019>021-085.
MARINE...None.

&&

$$

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