305
FXUS61 KBUF 120656
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
156 AM EST Wed Nov 12 2025

.SYNOPSIS...
Lake effect wet snow focused northeast of both lakes early this
morning will changeover to rain over the course of the day, though
not before causing a few additional inches of snow to accumulate
around the Buffalo, Niagara Falls, and Watertown Metro areas. Lake
effect precipitation will continue Thursday and into Friday, though
milder temperatures will allow for mostly plain rain. A brief period
of areawide dry weather expected early this weekend before unsettled
weather returns by early next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
A focus band of lake effect precipitation will continue to congeal
northeast of both lakes through the morning hours in response to a
mid-level shortwave trough moving southeast across southern Ontario
Province, with a track just north of the Great Lakes themselves.
Despite being cold enough for a lake response, temperatures aloft
will continue to warm through the morning hours. This will be just
slow enough to cause precip to start out as wet snow and make for
some locally slick travel this morning before a changeover to plain
rain occurs. In addition, the warm advective process will force for
a widespread plume of light snow to move east of the Genesee Valley
through the predawn hours.

Off Lake Erie, the initial band will set up across Niagara County
before slowly shifting southward into Orleans and Northern Erie
through daybreak as the flow veers. Off Lake Ontario the band will
set up over the Watertown Metro, then settle north towards the St.
Lawrence for a few hours before making a southward march back to the
Tug through the afternoon. Across the metro areas NE of both lakes,
a slushy 1-3 inches may be possible before the changeover to rain
occurs. Higher amounts (3-6") across the Tug Hill where snow will
continue to mix in through the day.

In the wake of the shortwave and as a strong ridge builds into the
Mississippi Valley, the flow will become more west-northwesterly
this evening and into tonight. The lake response will continue off
both lakes, especially southeast of Lake Ontario where deeper
synoptic moisture will remain. 850mb temps will cool back off by
degree or two to around -5C, marginal enough for the Lake Plains to
continue seeing rain while wet snow mixes in at the higher
elevations. A slushy inch or so of snow could accumulate across the
hilltops of the Southern Tier and the Tug Hill/Western Dacks.

&&

.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
Heading into the later half of the week, the trough that has been
set up across much of the eastern half of the CONUS from earlier in
the week will finally have a slight eastward shift as a shortwave
trough rounds its base helping to shove the pattern eastward
Thursday night and Friday. This will make way for a ridge to slide
overhead of the eastern Great Lakes for the start of the weekend.

Meanwhile at the surface, in the wake of an occluded frontal passage
Wednesday night, cool air around -5C at 850mb, lingering low level
moisture and northwest flow will support a few lake enhanced showers
to linger southeast of both lakes Erie and Ontario. While, yes it
will be cool enough to support lake enhancement, temperatures will
be warmer than earlier in the week and therefore precipitation type
should mainly remain as rain across the lower elevations and a mix
of rain/snow or pure snow possible across the higher terrain of the
Southern Tier and the Tug Hill.

As the moisture is stripped away from a combination of the exiting
surface low/frontal feature and incoming ridging, lake enhanced
showers will gradually peter out from west to east Friday and become
mainly dry Friday night as the surface high ridges over head of the
region.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
An amplified pattern to start this period will greatly depend upon
by the northern branch of the jet stream, where it will allow the
next storm system to bear down upon the region by the close of the
weekend.

After a dry start to the weekend due to surface high pressure
nearby, a southerly, mild flow combined with Pacific moisture from
the west will bring light rain across our region Saturday night and
Sunday, followed by a cold front/mid level shortwave trough later
Sunday that will maintain chances for showers late Sunday night
through Monday. As temperatures aloft Monday cool lake enhanced rain
and snow will become possible.

A southern stream closed low over the desert southwest early in the
weekend will open up and advance south of our region Tuesday.
Provided the downstream ridging/dry air overhead this will likely
end the lake response Monday night and into Tuesday. However there
is still a lot of uncertainty temporally and spatially with this
closed low, thus supporting a lot of uncertainty for the start of
next week.

&&

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
A shortwave trough just north of the Great Lakes will cause focused
bands of lake effect precipitation to congeal northeast of both
lakes through the morning hours, with a plume of warm advection
light snow moving east of the region. Inside the main lake effect
areas cigs/vsbys will be IFR or lower, with an improvement towards
mainly MVFR once rain becomes the dominant p-type. Outside the lake
effect ares, expect a mix of VFR/MVFR cigs and VFR vsbys.

These bands are expected to initially develop over KIAG and KART.
Off Lake Erie the band will slowly meander southward towards KBUF
through about 15z. Off Ontario the band will move north of KART this
morning before returning southward in the afternoon. Temperatures
across the region will initially be cold enough for snow before the
changeover to rain occurs. This changeover will occur around 12z off
Lake Erie, and around 15z east of Lake Ontario.

Otherwise, southwest winds wil be breezy today, especially on the
edges of the lake effect bands where gusts 20-25kts are expected.

Tonight, the lake effect precip will settle east-southeast of the
lakes, falling as rain across the Lake Plains (MVFR cigs/vsbys) with
wet snow on the higher elevations (IFR cigs and MVFR/IFR vsbys). The
main lake effect areas are expected to remain away from the TAF
sites, though chances for periodic impacts will be highest for KROC
and KJHW.

Outlook...

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

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

Saturday...Mainly VFR.

Saturday night and Sunday...MVFR/IFR in rain, possibly mixing with
freezing rain east of Lake Ontario at onset.

&&

.MARINE...
A deepening surface low will meander across Newfoundland through the
day today as a much weaker wave of low pressure moves across the
Great Lakes. With a cold airmass remaining overhead, this will cause
gusty southwest winds to continue on the lakes through the day
before turning west-northwesterly tonight. A brief period of Gales
will continue very early this morning on Lake Erie, otherwise SCAs
remain in place elsewhere as outlined below.

Waves are expected to remain 4 feet and greater through Thursday
evening on the eastern Great Lakes, and not until Friday when
surface high pressure approaches the lower Great Lakes will winds
and waves fall below small craft conditions.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...Winter Weather Advisory until 10 AM EST this morning for
     NYZ001-002-010.
     Winter Weather Advisory until 1 PM EST this afternoon for
     NYZ006>008.
MARINE...Small Craft Advisory until 4 AM EST Thursday for LEZ020.
         Gale Warning until 4 AM EST early this morning for LEZ040-
         041.
         Small Craft Advisory until 4 AM EST Friday for
         LOZ042>045.

&&

$$

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