044
FXUS61 KBUF 091903
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
203 PM EST Sun Nov 9 2025

.SYNOPSIS...
A complex storm system will bring a cold rain and North Country
wintry mix with all precipitation mixing with and changing to snow
through the afternoon and overnight hours. An early winter flow of
arctic air will lend to chilly conditions for Monday with
temperatures well below normal, brisk winds and lake effect snow,
that will increase in intensity Monday evening southeast of the
Lakes. Accumulating lake snows on a westerly flow Tuesday, with a
gusty wind before temperatures warm enough for precipitation to
become predominately rain mid-week.

&&

.NEAR TERM /THROUGH MONDAY/...
This afternoon surface low is entering SW Pennsylvania and is
forecasted to track just to the south and east of our region,
tracking across eastern New York through the evening...with a
secondary low forming and deepening off the Eastern seaboard Monday.

A deep long wave trough driving this surface low will drop down
across the Great Lakes this evening, forming a closed low over our
region by late tomorrow afternoon. This will allow for a much colder
airmass to push across the Lower Great Lakes tonight changing rain
to snow...with wintry mix east of Lake Ontario becoming all snow
later through the night.

As far as snow, a transition from rain to snow for areas near Lake
Erie and the Niagara Frontier through the late afternoon
hours...with the snow/rain line reaching through the Genesee Valley
by late this evening. Not until late tonight will the atmosphere
become sufficiently cold enough for snow for the Finger Lakes and
east of Lake Ontario...though by this time precipitation will become
much less.

Could see a decent accumulation of snow for Niagara-Orleans which
will lie closer to the 850 hPa temperature gradient, for which a
winter weather advisory will remain in effect. Several inches of
snow will be possible for northern Erie and Genesee Counties through
tonight. An upslope northwest flow will keep snow, and lake effect
snow across the Chautauqua Ridge, though as this flow becomes more
northerly...the better bands of snow will dive down into OH and NW
PA. Bordering counties of southern Erie and Cattaraugus could see an
inch or two of snow tonight.

A dry slot will reach across our region later tonight, tapering off
precipitation before synoptic moisture returns later Monday
afternoon with the approach of the closed upper level low. Outside
the aforementioned areas snow totals will be under an inch...but
still for most this will be the first measurable snow of the season.

For all tomorrow will be cold with most areas remaining around or
below the freezing mark. Adding in a brisk northwest flow, wind
chill values will be in the mid teens to mid 20s through the day.

&&

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
The mid-level trough axis begins to cross the Lower Lakes Monday
night into Tuesday morning, then exits off to our east while de-
amplification of the trough takes place by Tuesday afternoon. While
this occur...the core of the coldest air aloft is advertised to move
across the region Monday night, with H850 T`s briefly (6-10 hour
window) down to -10C to -12C before modifying as warm air advection
process take over Tuesday morning. This BRIEF window looks like it
may be our best chance too see accumulating lake effect snow E and
ESE of both lakes, especially off Lake Ontario. That said...BUFKIT
profiles look fairly unfavorable (shear) initially Monday evening
until a bit later in the evening-night, this is when flow veers from
SW to W-NW and becomes fairly uniform. This is also where moisture
increases and the environmental conditons line up enough to send
over lake equilibrium levels up to 12-15K feet. The main issue will
`likely` be residence time as it appears the band or bands may move
around some. Summing it all up...even with some band movement there
is enough confidence that we may see decent snowfall in areas.

Off Lake Ontario...a 280-290 WNW flow will direct a moderate to
heavy lake effect snow band or bands across Wayne, N. Cayuga, and
Oswego county beginning Monday evening and then lasting into Tuesday.
As was noted above...subtle wind shifts may limit accumulations but
have enough confidence at this point that we will see +6 inches of
snow in spots. Given that...will issue a Winter Storm Watch for
Wayne (eastern portion), N. Cayuga, and Oswego Co. but accumulations
will `likely` be highly variable across these counties. Additional
headlines may be needed for the remaining counties along the south
shore of the Lake Ontario where we could see lighter accumulations.

Off Lake Erie...while there will be accumulating snowfall east of
the lake the best potential may be found across far southwest
Chautauqua county and Chautauqua Ridge. An upstream connection to
Lake Huron may for a time may aid in decent accumulating snows late
Monday night into early Tuesday morning. However...the heaviest
snows from latest guidance shows the greatest snowfall over PA and
OH. Therefore will just continue to highlight the possibility of
potentially headline-worthy snows in the HWO for now.

Lake effect snows are advertised to shift northward Tuesday
afternoon off Lake Erie, and then Lake Ontario by Tuesday evening as
flow backs to the west then southwest. This will bring the lakes
snows across the Niagara Frontier and Watertown areas but should be
less intense and moving fairly rapidly northwards. Therefore
snowfall accumulations should be fairly light over any given spot.

Otherwise...outside of the lake snows it is look rather cold (highs
in the 30s) and blustery with winds gusting up to 30 to 35 mph.

Weak ridging over the region by Tuesday evening-night quickly moves
east as a surface low sinks southeast past the Hudson Bay sending a
front towards the eastern Great Lakes. Any remaining lake effect
snow or mix rain/snow showers now northeast of the lakes will be in
a very weakened state as the low/mid-levels warm further. Our area
will remain under the influence of upper-level trough Wednesday
through Wednesday night, with the aforementioned weak sfc wave
passing just to our north. This feature will bring mainly light
precipitation to our area which may be mixed with snow across the
higher terrain.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
An amplified pattern this period, with a cold upper level trough
beginning the period over the Great Lakes and Northeast, with a
building ridge of high pressure over the Central Plains.
Temperatures at 850 hPa in the mid single digits below zero Celsius
will be cool enough for a lake response...though thermal profiles
suggest a mix of rain and snow on a northwest flow.

Any lake snow will predominately be overnight and early morning,
before increasing mixing heights and solar heating destruct any
snowbands.

To start the weekend this upstream ridge of high pressure will build
towards our region. Any drying with this ridge will be temporary as
a digging trough over the Rockies will develop our next storm
system...one that could bring light rain back into our region by the
end of the weekend.

Temperatures at or below normal through much of this period until a
southerly flow ahead of the next storm system brings slightly above
normal warmth back into our region.

&&

.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
For the 18Z TAFS, widespread LIFR and IFR flight conditions are
found across the region, with a wintry mix that will become all snow
through the evening hours. While visibilities may improve a bit late
this afternoon as precipitation briefly ends...ceiling heights are
expected to predominately remain IFR or lower through tonight.

By tomorrow northwest flow will generate a few lake effect snow
showers, with greatest band strength off Lake Erie and near KJHW.
Otherwise light snow shower activity through the end of the TAF
cycle with ceiling heights improving to MVFR.

Outlook...

Monday...VFR/MVFR with scattered light snow showers southeast of the
lakes.

Tuesday...Lake effect snow and local IFR/LIFR southeast of the
lakes, VFR/MVFR with scattered light snow showers elsewhere.

Wednesday...MVFR/IFR with rain and snow showers, especially east of
the lakes. Windy.

Thursday...Areas of MVFR with rain and snow showers likely,
especially southeast of the lakes.

Friday...MVFR/VFR with a chance for rain and snow showers.


&&

.MARINE...
Low pressure across the southwest mid-Atlantic region will push
towards eastern New York this evening and then to New England
tonight. A stiffening northeasterly breeze will turn north-
northwesterly behind the system tonight and remain elevated through
Monday night. Winds will then turn westerly later Tuesday and
further strengthen. This will result in long duration SCA conditions
on all nearshore waters of both lakes as outlined below. It is not
out of the question that winds could hit gale force Tuesday night
through Wednesday night on the open eastern Great Lakes waters.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...Winter Weather Advisory until 7 AM EST Monday for NYZ001-002-
     007-008.
     Winter Storm Watch from Monday evening through Tuesday evening
     for NYZ004>006.
     Winter Weather Advisory from 7 PM this evening to 1 PM EST
     Monday for NYZ019.
MARINE...Small Craft Advisory until 7 PM EST Tuesday for LEZ040-041.
         Small Craft Advisory until 7 PM EST Tuesday for
         LOZ042>045.
         Small Craft Advisory until 10 PM EST Monday for LOZ030.

&&

$$

SYNOPSIS...Thomas
NEAR TERM...Thomas
SHORT TERM...AR
LONG TERM...Thomas
AVIATION...Thomas
MARINE...PP/Thomas