880
FXUS61 KBUF 221922
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
222 PM EST Wed Jan 22 2025

.SYNOPSIS...
After on last chilly day today, temperatures will begin to modulate
tonight and throughout the rest of the week into the weekend. The
last of the lake effect snow is now crossing north across the east
end of Lake Ontario, and has considerably weakened this morning.
After light widespread snow Thursday morning, lake effect will set
up northeast of the lakes late Thursday and Thursday night.

&&

.NEAR TERM /THROUGH THURSDAY/...
Low-level and surface ridging spread across the Ohio Valley and
eastern Great Lakes this afternoon has supported the end to the lake
effect snow off of Lake Erie and the weakening and advection of the
band northward on the east end of Lake Ontario this afternoon. This
being said, all lake effect snow warnings have been cancelled.

A shortwave trough is in the midst of pivoting through the base of
the longwave trough today through the end of the week. Its
associated weak surface low will make its way across the central
Great Lakes, forcing the surface ridge east off the Atlantic
coastline. As a result, steady warm air advection with southerly low
level flow will result in low temperature readings today to occur
early in the evening, with lows in the upper single digits to the
low teens. Temperatures will then modulate and gradually ridge
throughout the remainder of the night. Otherwise it will be mainly
dry with a considerable amount of mid and high level cloud cover
blanketing the region due to an increase in low level moisture.

The aforementioned surface low will slide northeast of the area
Thursday with its attendant cold front sliding east across the area
late Thursday and Thursday night. After a dry start Thursday
morning, some light widespread snow is possible ahead of the frontal
passage due to increasing moisture and convergence along the
system`s front late Thursday into Thursday night. This front will
also spark a rebirth of lake effect snow northeast of both lakes
Erie and Ontario Thursday evening right around rush hour across the
Buffalo and Watertown metro areas. This being said, snowfall amounts
will be light with a little over an inch possible.

&&

.SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY NIGHT/...
A series of weak troughs will cross the eastern Great Lakes through
the end of the week, with each bringing some minor impacts, mainly
in areas of lake enhancement east of the lakes.

The first mid level trough and weak surface cold front will cross
the eastern Great Lakes Thursday evening. Away from lake influences,
this feature will only bring increased cloud cover and possibly a
few scattered, light snow showers. Expect the low level trough to
become lake enhanced as it crosses each lake.

Off Lake Erie, a band of lake enhanced snow across Buffalo and the
Niagara Frontier early Thursday evening will move south to the
higher terrain east of Lake Erie late evening through the early
overnight. Weak lake effect snow showers will then linger across the
western Southern Tier Friday, before a weakening band of lake effect
snow showers moves back north towards Buffalo late Friday and Friday
night before dissipating by Saturday morning. Snowfall amounts
should be relatively minor given the weak instability and transient
nature of the band. Expect a general 2-4" from the Buffalo Metro
area southward into the higher terrain just east of the lake. There
may be a few localized 4-6" amounts where the snow persists the
longest over the 36 hour period.

Off Lake Ontario, expect a band of lake enhanced snow to develop
near Watertown Thursday evening, then swing south to Oswego County
overnight. A band of lake effect snow will then continue across
portions of Oswego County, possibly clipping northern Cayuga County
at times Friday. There is a good deal of uncertainty still in band
placement and intensity during this time frame, but if the more
aggressive Canadian GEM verifies, locally moderate accumulations are
possible. In general, expect 4-6" from near Watertown southward into
Oswego County. What remains of the lake effect snow will move back
north towards Jefferson County Friday night before dissipating early
Saturday.

Saturday, surface high pressure will build from the Ohio Valley and
eastern Great Lakes early in the morning to off the eastern seaboard
by evening. The next in a series of troughs will approach the
eastern Great Lakes late in the day, with an increasing chance a few
light snow showers east of Lake Erie and Lake Ontario.

Temperatures will still run below average through the end of the
week, but not nearly as cold as the past few days.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
A progressive mid-level ridge will move east of the region Saturday,
with a brief period of zonal flow aloft before broad longwave
troughing begins to work back in from the west Saturday night into
Sunday.

An area of surface low pressure and attendant cold front will then
slide east across the area Saturday night into Sunday with another
round of light synoptic and locally heavier lake enhanced snows
expected. In the wake of the trough, temperatures at 850mb will cool
enough to support lake effect east-northeast of both lakes into at
least Sunday night. Typical long range uncertainties persist in the
arrival time of the greater forcing and moisture from this trough so
have stuck close to blended ensemble guidance/continuity with
chances for snow lingering into Tuesday, though guidance is hinting
that 850H temps may actually warm enough by Monday be marginally
supportive of lake effect. For now, chances remain greatest in the
typical lake effect/upslope areas east of both lakes.

Temperatures this period will be much warmer compared to earlier in
the week, and may even approach climatological norms over the
weekend.

&&

.AVIATION /20Z WEDNESDAY THROUGH MONDAY/...
Mainly VFR conditions prevail across the western TAF sites this
afternoon, with the last of the weakened lake effect snow off of
Lake Ontario passing north into northern Jefferson county producing
light snow and MVFR/IFR visibilities and impacting KART. This snow
will then continue to push north into the Saint Lawrence Valley and
north of KART late this afternoon.

Conditions will then improve to VFR across all TAF sites tonight
with high clouds building in from west to east across the area
tonight.

Outlook...

Thursday...Mainly VFR. Some weak lake effect snow and IFR/MVFR
restrictions possible northeast of the lakes in the afternoon.

Thursday night through Monday...IFR/MVFR restrictions possible
downwind of the lakes in lake effect snow at times...otherwise
mainly VFR.

&&

.MARINE...
Winds will back to southerly and slacken some today as high pressure
slides from the Ohio Valley to the mid-Atlantic and New England
coastlines...thereby allowing for the eventual discontinuance of
most of the existing Small Craft Advisories. The one possible
exception to this will be at the far eastern end of Lake
Ontario...where increasing southerly flow late today and tonight may
result in continued lower end advisory-level conditions right
through tonight.

A brisk southwesterly to westerly flow will then follow for Thursday
and Thursday night...likely necessitating the next round of Small
Craft Advisories during that time frame.

&&

.CLIMATE...
One quick climate note...the temperature at Buffalo dropped to at
least -3 degrees Fahrenheit this morning. This is the first time
since February 1, 2019 that the temperature at Buffalo has fallen
below zero degrees...a span of nearly six years. The temperature at
Rochester also fell below zero this morning...for the first time
since February 4, 2023.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...None.
MARINE...Small Craft Advisory until 7 PM EST this evening for LOZ045.

&&

$$

SYNOPSIS...EAJ
NEAR TERM...EAJ
SHORT TERM...Hitchcock
LONG TERM...AR
AVIATION...EAJ
MARINE...EAJ/JJR
CLIMATE...JJR