803
FXUS61 KBUF 081925
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
225 PM EST Wed Jan 8 2025

.SYNOPSIS...
A northwest flow of cold air will continue to support fairly
widespread light lake effect snow showers across much of the region
through Thursday morning. A gusty northwest breeze will
continue to produce some limited blowing snow and cold wind chills.
High pressure building in from the west will end the lake snows from
west to east Thursday, bringing dry weather for Friday. A trough
crosses the region Friday night through Saturday with another round
of light snow.

&&

.NEAR TERM /THROUGH THURSDAY/...
An expansive, vertically stacked closed low will continue to spin
over the Canadian Maritimes through Thursday. This will maintain a
cold and moist cyclonic northwest flow across the eastern Great
Lakes. The short northwest fetch and relatively low inversion
heights will continue to limit snow intensity, with snow intensity
depending on moisture from any shortwaves and upstream lakes.

A mid level trough will move south across the eastern Great Lakes
this afternoon which will bring deeper moisture along and behind the
trough axis. As a result, lake snows will increase in coverage and
intensity tonight, especially southeast of Lake Ontario. An upstream
connection to Lake Huron may also enhance the snowfall across the
higher terrain of southwest Chautauqua County through tonight. The
Georgian Bay connection will also continue to meander across the
area between Buffalo and Rochester down into the western Finger
Lakes, with isolated better snowfall rates.

The period of deeper moisture and ascent from the passage of the mid
level trough will bring some light non-lake effect snow to the North
Country as well, especially across the higher terrain of the Tug
Hill Plateau and western foothills of the Adirondacks from upslope
flow.

Thursday, the vertically stacked low over the Canadian Maritimes
will finally start to drift east, and surface high pressure will
build into the Ohio Valley and eastern Great Lakes later in the day.
This will bring a gradual west to east decrease in lake effect snow
showers through the day, although a few may linger into the evening
southeast of Lake Ontario.

The greatest additional snow accumulations will be southeast of Lake
Ontario and southeast of Lake Erie (mainly southwest Chautauqua
County). For these locations an additional 3-5" is possible through
Thursday morning, with a couple additional inches possible during
Thursday off of Lake Ontario. Elsewhere, snow accumulations will
mainly be less than an inch, although localized amounts of a few
inches are possible in narrow bands outside these areas.

It will continue to be quite blustery through Thursday, with wind
gusts running in the 20-30 mph range and locally 35 mph southeast of
Lake Ontario. This will produce some limited blowing and drifting
snow in open areas with snow on the ground. The wind will also keep
wind chills in the single digits, and below zero across higher
terrain.

&&

.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY NIGHT/...
An upper level shortwave ridge will move into the eastern Great
Lakes region Thursday night. This should put an end to any lingering
lake effect snow showers. Cold, with lows in the teens across
western NY and the single digits to near zero east of Lake Ontario.
Surface high pressure will move across the forecast area Friday and
while it will still be cold, mostly sunny skies and calm winds will
start out the day. Temperatures will remain below the freezing mark
Friday, with highs in the 20s.

An upper level ridge and anticyclonically curved jet will build over
the western Atlantic Friday night. A positively tilted trough will
move into the Great Lakes region. A southern stream system across
the Gulf coast states will move off the Mid-Atlantic coast by
Saturday. The northern and southern stream systems will phase off
the Atlantic coast minimizing impacts to the eastern Great Lakes
region. With that being said, moisture will increase ahead of the
approaching trough Friday night. The greatest upward motion and
moisture in the DGZ will occur Friday night. Light snow will linger
into Saturday before transitioning to a brief period of lake effect
snow east of Lake Erie and Lake Ontario through Saturday night.
Snowfall amounts will range from 1-3" Friday night through Saturday.
An additional 1-3" is possible east of the Lakes through Saturday
night.

Temperatures may reach freezing across the lower elevations
Saturday. Highs will range from the low 30s across the lower
elevations to the upper 20s across the higher terrain. Lows will
fall to the teens to low 20s Friday night and Saturday night.

&&

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
Deep troughing spread across much of the CONUS this weekend and into
the first half of the week will support multiple shortwaves to drop
southeast across the Great Lakes. This pattern will not only support
below normal temperatures throughout the period but additionally
support active snowy weather throughout.

Looking into the details, brief mid-level ridging Sunday will
support surface high pressure to spread across the region. Ongoing
lake effect snow will gradually peter out Sunday as low-level dry
air filters into the region.

The next mid-level trough and corresponding surface low will dive
southeast across the Great Lakes Monday with a shortwave trough to
follow in its wake Tuesday. After an initial shot of widespread
synoptic snow Monday, expect lake effect snow to follow Tuesday and
Wednesday.

&&

.AVIATION /20Z WEDNESDAY THROUGH MONDAY/...
Expansive low pressure stalled over the Canadian Maritimes will
continue to support cold, cyclonic northwest flow across the eastern
Great Lakes through tonight, producing a plethora of mainly light
lake effect snow showers and flurries across much of the region.

In steadier snows vsby will drop to 1-2SM. The most likely terminals
to see periods of IFR in the lake effect snow showers are KROC and
KJHW through tonight. KART will also likely see some IFR tonight
from the general wrap around light snow. KBUF and KIAG are the least
likely to see IFR, but it cannot be ruled out if a narrow band
crosses the area.

It will continue to be quite blustery today through tonight with
wind gusts in the 20-30 knot range. This will produce some blowing
snow on airfields with snow on the ground.

Snow will taper off from west to east during the day Thursday, with
mainly VFR flight conditions expected by Thursday evening.

Outlook...

Thursday night and Friday...Mainly VFR.

Friday night through Saturday...MVFR/IFR in areas of snow.

Sunday and Monday...VFR/MVFR with a chance of a few light lake
effect snow showers east of the lakes.

&&

.MARINE...
Moderate to strong northwesterlies will continue through
Thursday, bringing a long period of higher end Small Craft
Advisory conditions. The higher winds and wave action will be on
Lake Ontario, with somewhat lower winds on Lake Erie through
the period. High pressure will build into the eastern Great
Lakes Friday, finally bringing an end to the elevated winds and
wave action.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...Winter Weather Advisory until 7 AM EST Thursday for NYZ004>006-
     019.
MARINE...Small Craft Advisory until 1 AM EST Friday for LEZ040-041.
         Small Craft Advisory until 7 AM EST Thursday for
         LOZ030.
         Small Craft Advisory until 4 AM EST Friday for LOZ042.
         Small Craft Advisory until 1 PM EST Friday for LOZ043-044.
         Small Craft Advisory until 7 AM EST Friday for LOZ045.

&&

$$

SYNOPSIS...Apffel/Hitchcock
NEAR TERM...Apffel/Hitchcock
SHORT TERM...HSK
LONG TERM...EAJ
AVIATION...Apffel/Hitchcock
MARINE...Apffel/Hitchcock