206
FXUS61 KBUF 060041
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
741 PM EST Wed Feb 5 2025

.SYNOPSIS...
High pressure will exit off to our east tonight. Low pressure
tracking across the region will then bring a mix of snow, sleet and
freezing rain late tonight into Thursday...before changing to rain
for most areas south of Lake Ontario by Thursday afternoon. East of
Lake Ontario the precipitation will remain mostly in the form of
snow...with some freezing drizzle possibly mixing in at times
Thursday afternoon and evening. Colder air moving in Thursday night
and Friday will then bring accumulating lake effect snow east of
Lake Ontario...along with a period of gusty southwesterly to
westerly winds.

&&

.NEAR TERM /THROUGH THURSDAY/...
As of early evening the persistent light snow showers/flurries have
all but ended...save for a patch of leftover flurries near the
Oswego/Jefferson county border. These will wind down this evening as
the responsible low level convergence zone gives way to a developing
southeasterly flow out ahead of the next system...with dry weather
and a general southwest to northeast increase in cloud cover
otherwise expected to prevail through the early overnight hours.

After that (06z)...we will see precipitation chances increase from
southwest to northeast through the rest of the night and into
Thursday as elongated low pressure pushes into our region from the
Ohio Valley and central Great Lakes. The onset of precipitation will
coincide with the leading edge of a strengthening LLJ ( +50 knots)
arriving across the forecast area. P-type will initially be snow,
but as warmer air quickly arrives aloft a transition over to sleet
and then freezing rain will occur before turning to all rain. The
greatest likelihood to see a period of freezing rain will be south
of the Thruway, with lesser chances to the north where precipitation
may stay all snow or mix with a bit of sleet (North Country).
Additionally...while very `light`, there is a potential that
precipitation could switch to a little freezing drizzle across the
North Country late in the afternoon and into the evening. BUFKIT
sounding profiles do suggest this occuring as moisture will deplete
within the DGZ. For this latter area ice accumulations of under a
tenth of an inch will be possible along with expected snowfall
amounts of 2 to 4". Elsewhere snowfall amounts will be minor (< 2"),
with up to a tenth of an inch or ice accumulation possible for areas
south of the NYS Thruway. Given all this...Winter Weather Advisories
remain in effect as outlined below.

&&

.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY NIGHT/...
Cold air will filter back in across the region, changing any
lingering mixed precip back over to all snow Thursday night. Main
snow accumulations (inch or two) first half of the night expected
across the Tug Hill and western Dacks.

Coupled with this CAA will be a 50 knot LLJ around 2-3 kft above the
surface. Favorable momentum transfer will create winds gusting to
near 45 mph downwind of both Lake Erie and Ontario. Away from the
lakes southwesterly gusts will still be within the 30-35 mph range.

This pool of colder air aloft will raise lake induced equilibrium
levels to around 8-9 kft feet, which with increasing convergence
along the long fetch of Lake Ontario will create favorable lift for
a band of lake effect snow to develop. Wind shear and depth of
colder air early in the night will likely keep the snowband
unorganized, but as the night carries on, a WNW flow will direct a
band of lake snow across southern Lewis and Oswego counties.

Winds veer a bit sending this band squarely into Oswego County
Friday morning where it may produce a few inches of snow before
weakening some during the day Friday as a weak midlevel trough
transverses Lake Ontario, but the snowband should strengthen again
late afternoon and overnight as a now upstream connection to
Georgian Bay occurs. Overall snow amounts of several inches each 12
hour period through Friday night will be manageable, but in total
could not rule out advisory to low end warning amounts. Will
maintain this mention in the HWO product. Otherwise, a fairly quiet
end to the work week expected with just some scattered light snow
showers expected.

High pressure slides off the delmarva Saturday, thus aside from some
lingering light lake snow showers east of Lake Ontario, expect a
mainly dry start to our Saturday. Once again this will be short-
lived as a strengthening area of low pressure approaches from the
mid-Mississippi/lower Ohio valleys Saturday afternoon, possibly
bringing some light snow to portions of western NY by later
Saturday. Model consensus remains in very good agreement on the
track of this low, however the track is now a bit further south. If
this solution comes to fruition, p-type issues would be suppressed
to near or even completely south of the NY/PA line with all snow for
most, if not all of western and northcentral NY Saturday night. That
said, this does appear that it will be a widespread impactful
snowfall, with the potential for at least high-end advisory to low-
end warning amounts across a good chunk of the area. Will add
mention in the HWO.

&&

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
Another blast of cold air and possible round of northwest flow lake
effect snow will be possible Sunday and Sunday night behind the
departing low pressure system, however amounts look very manageable
at this point. High pressure ridges across the region bringing a
mainly dry start to the new work week, although a few nuisance lake
driven snow showers may linger east of Lake Ontario.

Next cold front approaches from the northwest Monday night/Tuesday,
while at the same time an area of low pressure passes by well
to...or just to our south/southeast depending on your model of
preference. Thus with a good amount of disagreement with regard to
these two features, forecast confidence is low during this time.
Canadian high pressure then tries to ridge south into the area by
Wednesday, although that will depend on what happens with the
features earlier in the work week. Stay tuned.

&&

.AVIATION /01Z THURSDAY THROUGH MONDAY/...
VFR conditions can be expected through the first half of tonight...
with gradually increasing/lowering high and mid level clouds from
southwest to northeast.

Conditions will then deteriorate from southwest to northeast after
06z tonight as a trough of low pressure approaches from the
southwest. Most areas from KROC south and west will see CIGS
deteriorate to MVFR by daybreak Thursday, with IFR possible across
the Southern Tier (KJHW). MVFR CIGS will reach the North Country
(KART) by mid to late morning, while widespread IFR/possible LIFR
CIGS become common south and west of KROC by late morning, lasting
well into the afternoon.

The trough of low pressure will also bring a period of mixed
precipitation late tonight through the day Thursday. Initial swath
of light snow will overspread western NY from the southwest between
07Z-11Z...bringing a period of IFR/possible LIFR VSBYs to locations
from KROC south and westward. During Thursday a period of light
freezing rain is expected at KJHW during the morning hours (~11Z-15Z
window)...while further north KBUF/KIAG/KROC should largely see a
switchover from snow directly to rain (with just a very quick
transition period of mixed precip possible) from 14-17z. Across the
eastern Lake Ontario Region (including KART) snow will arrive by mid
morning with IFR/possible LIFR VSBYs expected there through the end
of the TAF period...with some freezing drizzle also becoming
possible during the afternoon and early evening.

Outlook...

Thursday night...Becoming very windy northeast of the lakes with
gusts to 35-40 knots likely...otherwise expect lingering IFR
ceilings east of Lake Ontario to give way to a mix of mainly
VFR/MVFR...with lake effect snow and local IFR then developing
across the Tug Hill region late.

Friday...Lake effect snow/local IFR southeast of Lake Ontario...with
MVFR/VFR and a chance for light snow showers elsewhere.

Saturday...VFR/MVFR with a chance of snow late in the day.

Sunday...MVFR/VFR with a chance for light snow showers and local IFR
southeast of the Lakes.

Monday...MVFR/VFR.

&&

.MARINE...
Light winds and minimal wave action on both lakes through this
evening.

Low pressure will start to advance toward the lower Great Lakes
tonight with moderate southeasterlies developing veering to
more southerly during the day Thursday.

Southwest then west winds will ramp up as the low pressure system
exits and sends a cold front through later Thursday into Friday with
possible gales on Lake Ontario. Winds will not be quite as strong on
Lake Erie, but still looking at winds to 30 knots.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...Winter Weather Advisory from 4 AM to 10 PM EST Thursday for
     NYZ006>008.
     Winter Weather Advisory from 4 AM to 1 PM EST Thursday for
     NYZ012>014-085.
     Winter Weather Advisory from 1 AM to 1 PM EST Thursday for
     NYZ019>021.
MARINE...Gale Watch from Thursday evening through Friday afternoon for
         LOZ042>045-062>065.

&&

$$

SYNOPSIS...AR/JJR
NEAR TERM...AR/JJR
SHORT TERM...JM/Thomas
LONG TERM...JM
AVIATION...JM/JJR
MARINE...AR/TMA