826
FXUS61 KBUF 242315
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
615 PM EST Mon Nov 24 2025

.SYNOPSIS...
Dry weather and partially sunny skies will continue this afternoon
and into this evening as surface high pressure builds east into the
Lower Great Lakes. The area of low pressure will enter the region
Tuesday, supporting the return of rain. A strong cold front will
pass Wednesday, ushering in gusty winds and localized lake effect
snow east of the lakes Wednesday night through the end of the week.

&&

.NEAR TERM /THROUGH TUESDAY NIGHT/...
Broad surface high pressure centered over the Ohio Valley early this
afternoon will continue to slide east towards the Mid-Atlantic
tonight, while ridging northward across the lower Great Lakes. Dry
air associated with the ridge, has halted upslope showers across the
Tug Hill, with only clouds lingering as of the noon time hour.
Otherwise across the west, some mid to high level clouds are
building east across WNY due to some warm air advection.

Tonight, dry weather will prevail despite the surface ridge exiting
east into the Atlantic.

A diffuse mid-level shortwave trough will move out of the Ohio
Valley Tuesday. As a result, a warm front will pass from southwest
to northeast across the region supporting widespread rain showers.
These showers should reach the North County by late Tuesday
afternoon into Tuesday evening, with activity tapering off to light
showers/drizzle across WNY. The light showers/drizzle will then
linger into Wednesday morning.

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY/...
...HEAVY LAKE EFFECT SNOW LIKELY WEDNESDAY NIGHT THROUGH FRIDAY
NIGHT...

Main change with this update...Winter Storm Watch expanded to
include northern Erie and Genesee counties. Canadian RGEM continues
to suggest an initial band placement north of the other guidance
Wednesday night through the first half of Thursday. While the RGEM
might be a little too far north, there is a well understood
southward bias in most model guidance in single band WSW flow lake
effect events, especially early in the season. The RGEM typically
does not show this bias.

A cold front will move east across the area Wednesday afternoon and
early evening, producing a few showers, especially in the afternoon.
The cold front will exit east of the area early Wednesday evening,
with a deep longwave trough carving out across the Great Lakes
through Thanksgiving Day allowing cold air to pour into the Great
Lakes. Initial cyclonic SW flow will gradually veer WSW and W late
Wednesday night through Thanksgiving Day, then more NW Thursday
night through Friday, supporting mobile bands of lake effect snow.

Lake Erie...

Wednesday evening, initial lake band will develop over the Buffalo
Metro area, or even the north side of the metro. The airmass is not
that cold initially, so this initial band will be rain or a rain/wet
snow mix early in the evening. Cold air will deepen overnight,
supporting a change to all snow by late evening or the midnight hour
as the band settles slowly south, crossing the Buffalo Metro area.
The band will likely linger over the southern half of the Buffalo
Metro and into southern Genesee County through the first half of
Thanksgiving Day before settling farther south across the Boston
Hills and Wyoming County later in the afternoon.

This first phase of the event is extremely uncertain given model
differences in band placement and very marginal temperatures to
change precip to all snow. There is a wide range of possibilities,
but if the change to all snow is early enough, warning criteria snow
is possible across portions of northern Erie and Genesee counties,
especially just south and east of the City of Buffalo and in
southwest Genesee County.

Lake Ontario...

As is often the case, Lake Ontario lake effect will take longer to
organize. A relatively weak band of rain or rain/snow mix will
develop overnight Wednesday night across central and northern
Jefferson County, with some unrelated upslope across the Tug Hill
Plateau. This will continue through Thanksgiving Day, with the lake
effect settling south across Watertown and towards the northern Tug
Hill region. The lake effect may not be too organized or strong
through Thanksgiving Day, with more shear and less favorable low
level convergence compared to Lake Erie.

Winds...

It will turn quite windy along and immediately behind the cold
front, with gusts of 40-50 mph likely later Wednesday afternoon
through Wednesday night close to Lake Erie and across the Niagara
Frontier. The strong winds will spread east and inland across the
rest of the area Thursday as surface winds veer more westerly, with
gusts of 40-50 mph possible areawide. A Wind Advisory may eventually
be needed for most, if not all of the area. The strong winds will
result in blowing and drifting snow in lake effect areas, although
relatively mild temperatures and higher density snow may help to
mitigate this to some extent.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
Thursday night through Friday night, boundary layer flow will
steadily veer to the northwest, carrying lake effect snow southward
off both lakes. Off Lake Erie, the snow will focus mainly across
Chautauqua and Cattaraugus counties, with an upstream connection to
Lake Huron likely enhancing the snow. Off Lake Ontario, lake effect
snow east of the lake centered on the Tug Hill Plateau and
intensifying Thursday night through early Friday. Lake effect snow
will then spread out across a wider swath southeast of Lake Ontario
later Friday through Friday night with lessening intensity.

In addition, abundant wrap around moisture, synoptic scale ascent
from the passing mid level trough, and upstream moisture/bands from
Lake Huron will likely result in fairly widespread occasional light
snow showers later Thursday night through Friday morning with
widespread light accumulations even outside of the main lake effect
areas.

Strong winds will continue Thursday night through Friday, with gusts
of 35-45 mph producing blowing and drifting snow.

Lake effect snow southeast of the lakes will weaken and shrink in
areal coverage later Friday night and Saturday morning, coming to an
end completely by Saturday afternoon.

The next low will move out of the mid section of the nation Sunday
through Monday, with chances of synoptic scale precipitation
increasing. Model guidance diverges significantly on the track and
intensity of this system, but in general expect a gradual warming
trend with any snow transitioning to mainly rain.

&&

.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
For the 00Z TAFS VFR flight conditions are found and these
conditions will prevail for the next 12 to 18 hours with a gentle
southerly flow.

A southern stream shortwave will bring a period of rain tomorrow,
with this rain arrival between 15 and 21Z from west to east. Ceiling
heights will lower to MVFR within the rain...and to higher terrain
IFR by mid afternoon for the Southern Tier (KJHW). Visibilities
should stay VFR through most if not all of the TAF cycle...with
perhaps some MVFR visibilities towards the final hours of the TAF
cycle as low level moisture builds.

Outlook...

Tuesday night...MVFR/IFR with rain.

Wednesday...VFR/MVFR with showers. Turning very windy mid-day. Lake
effect snow with IFR flight conditions starts Wednesday night.

Thursday through Friday...VFR/MVFR with a chance of snow showers.
Heavier lake effect snow with IFR/LIFR east of Lake Erie and Lake
Ontario. Very windy.

Saturday...VFR/MVFR with a chance (Erie) and likely (Ontario) of
snow showers east/southeast of Lakes Erie and Ontario.

&&

.MARINE...
Winds and waves will continue to subside this afternoon as high
pressure ridges across the eastern Great Lakes.

Strong low pressure will move from the upper Great Lakes Wednesday
to Quebec by late Thursday, supporting a strong cold front to plow
across the lower Great Lakes late Wednesday afternoon and evening.
Westerly winds will quickly increase along and behind the cold
front, with an extended period of gales likely on Lake Erie and Lake
Ontario from late Wednesday through Thursday night.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...Winter Storm Watch from late Wednesday night through Saturday
     morning for NYZ006>008.
     Winter Storm Watch from Wednesday evening through Thursday
     afternoon for NYZ010-011.
     Winter Storm Watch from Wednesday evening through Friday
     evening for NYZ012-019-020-085.
MARINE...Gale Watch from Wednesday afternoon through late Thursday
         night for LEZ040-041.
         Gale Watch from Wednesday afternoon through Friday
         evening for LOZ042>045-062>065.

&&

$$

SYNOPSIS...EAJ
NEAR TERM...EAJ
SHORT TERM...Hitchcock
LONG TERM...Hitchcock
AVIATION...Thomas
MARINE...EAJ/Hitchcock/TMA