721
FXUS61 KALY 271931
AFDALY

AREA FORECAST DISCUSSION
National Weather Service Albany NY
231 PM EST Thu Nov 27 2025

.SYNOPSIS...
Lake effect snow will move into the western Adirondacks
early tonight and slowly shift southward into the Mohawk Valley,
Capital Region and northern Catskills Friday morning.  Heavy snow
accumulations will occur where the bands set up mainly west of the
Capital Region with some higher total over the northern Taconics and
northern Berkshires.  High pressure builds in Saturday with cold and
dry weather before a pair of systems impact the region Sunday into
Monday morning, and also Tuesday with rain and snow, though the
Tuesday system could bring a widespread accumulating snow.

&&

.SHORT TERM /THROUGH SUNDAY/...
Key Messages:

- A period of lake effect snow is expected tonight into Friday
  across the western Adirondacks, Mohawk Valley and northern
  Catskills. Snowfall amounts of 4 to 12 inches are expected in
  the most persistent lake effect bands.

- A Lake Effect Snow Warning remains in effect for Herkimer and
  Hamilton Counties with Winter Weather Advisories for Fulton,
  Montgomery, Schoharie, Counties.

- A Winter Weather Advisory for northern Berkshire and eastern
  Rensselaer Counties for lake effect and upslope enhancement 10
  am Fri to 10 pm Sat for 2-5".

- Wind gusts between 30 and 45 mph, especially on Friday, could
  lead to patchy to areas of blowing and drifting snow.

Discussion:
As of 230 PM EST...

Happy Thanksgiving!

A positively tilted mid and upper level trough continues to be
situated over the eastern CONUS with an H500 closed circulation
over southeast Ontario and southwest Quebec this afternoon. In
the low to mid-level southwest flow, most of the lake effect
activity has been confined to the St Lawrence River Valley and
west of the forecast area with occasional snow showers drifting
into the western Adirondack. Mostly cloudy, mainly dry and cold
conditions have persisted across most of eastern NY and western
New England thus far. Any snow accumulations prior to nightfall
will be an inch to two well north of Route 28 and Old Forge.

A sfc trough and a mid and upper level short-wave will move
across the region tonight. This will allow the Lake Ontario
snowband to begin to settle southward over the western Dacks.
Snowfall rates could reach an inch or even two an hour due to a
multi-lake connection off Lake Superior and Georgian Bay. Lake
induced instability on upstream soundings is conditional with
the inversion height above 8 kft AGL. The band should begin to
move southward between 2-5 am, and may be just north of I-90 in
the Mohawk Valley by 7 am and could impact the I-90 corridor
7-10 am based on the 3-km NAM and HRRR. The NAM is a little
slower than than the NAM, but the headlines look good and remain
up for the western Dacks and western Mohawk Valley (including
southern Herkimer Co) with warnings for 4-12". The central
Mohawk Valley including Fulton and Montgomery Counties may get
2-6" of snow, as well as Schoharie County in the northern
Catskills may get 3-6". The band pushes southward in the
afternoon into the Capital Region, northern Taconics and
Berkshires. Some 1-2" amounts in the Capital Region are
possible. However, due to upslope enhancement with the lake band
2-5" are possible in the Rensselaer Plateau of eastern
Rensselaer and the northern Berkshires. The Winter Wx Advisory
criteria is only 3" and due to the holiday weekend, an advisory
makes sense for these 2 area. The Capital Region will be
monitored if higher totals area realized, but special weather
statements may be used to track the band tomorrow into tomorrow
evening. The lake effect band may intensify again in the pm with
less directional shear below 700 hPa, and persistent
conditional lake instability. The band exact placement is in
question on how far south of the Tri Cities it will be in the
mid pm though it may migrate slightly further north in the pm to
early evening.

Blowing and drifting snow is expected with a tight sfc pressure
gradient in the wake of the sfc trough and some momentum
transfer. Gusts will be mainly 25-40 mph, though a few higher
ones can not be ruled out. Use caution if out on the roads
tomorrow if encountering any lake bands or heavy snow showers.
Lows will be in the 20s to around 30F. Black Friday will be
blustery and cold with highs in the mid 30s to around 40,
except mid 20s to lower 30s over the mtns.

The lake effect band begin to lose its extension in the early
evening with the inversion height starting to lower and the multi-
lake connection lost. Also, the flow begins to shift
anticyclonic. Some light snow amounts may continue in the Hudson
River Valley including the Capital Region, as well as the
northern Catskills/Taconics and Berkshires. Some locations in
the western New England favored upslope areas are forecasted to
receive 2-5" again. The lake effect snow showers taper to
scattered flurries by Saturday morning. The winds will begin to
slightly subside with lows in the 20s with some teens over the
Adirondacks Park.

High pressure builds in Saturday with the winds continuing to
decrease with partly to mostly sunny and cold conditions. Highs
will run about 5-10 degrees below normal with mid 30s to around
40F in the valleys and 20s to lower 30s over the terrain again.

Saturday night into Sunday...high pressure shifts east of the
Mid Atlantic and southern New England corridor with mid level
ridging weakening over the Northeast, as low pressure approaches
from the Midwest and lower Great Lakes Region. Clouds rapidly
increase with light snow or snow showers moving into the region
late Sat night. Lows fall back into the teens and 20s. The
isentropic lift increases across the region on Sunday, as the
cyclone moves towards southeast Ontario and Georgian Bay. A
period of snow to rain will occur in the lower elevations with
the south to southwest flow maintaining snow over the southwest
Dacks. We may need an advisory for 2-6" of snow or so over
northern Herkimer and Hamilton Counties later. It will become
breezy with highs still below normal in the 30s to lower 40s.
Snow accums in most locations outside the will be a coating to
an inch before the transition to rain outside the Adirondack
Park and southern Greens.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
Key Messages:

- The 13Z NBM 24-hr probabilities >4" of snowfall ending 7 am
  Wed across eastern NY and western New England are 25-40% for
  the potential storm system Tue-Wed.

Discussion...

The cold front to the weekend system moves through Sunday night
with a brief lake effect connection into Monday for light snow
accums over the western Dacks, western Mohawk Valley and
northern Catskills. Lows fall back into the 20s with some teens
over the southern Greens and southern Dacks. Monday will be
chilly with high pressure briefly building in before clouds
start to increase from the south and west late in the day.
Highs will still run about 5-10 degrees below normal with mid
30s to around 40F in the major valleys and 20s to lower 30s over
the hills and mtns.

The frontal boundary stalls near the mid Atlantic Seaboard and
the Southeast Monday night. Low pressure organizes over the
Southeast, as separate northern stream disturbance will be
digging in from the Missouri and Midwest corridor. Some over
running light snowfall may begin to move into the forecast area
late Monday night with a better thrust of snow for Tue. The
latest ensembles/NBM/medium range guidance continues to show a
storm impacting the forecast area Tue-Wed morning. The track of
the system shows spread in the ensembles and the "fuzzy"
clustering, though the latest NBM guidance yields 25-40% probs
for >4" of snow for the forecast area Tue-Tue night. The
evolution and track will make a big difference for a light
accumulating snowfall into the Capital Region vs. a heavier one.
We have likely PoPs for accumulating snowfall Mon night-Tue
night across the forecast area with temps running colder than
normal with lows in the teens and 20s and highs in the 20s to
lows to mid 30s. The predominant ptype will be snow. Trends on
this storm will be monitored over the next few days.

Midweek onward...the storm system pulls away Wed with some
lingering light snow and snow showers with high pressure
building in. A strong cold front approaches from southeast
Canada, the Great Lakes Region and Midwest for Thu with a chance
of snow showers and flurries from the Capital Region north and
west. Temps will continue to run below normal for early
December.

&&

.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
Through 18z Friday...VFR conditions prevail across all TAF sites
this afternoon despite clouds largely remaining in place in the
wake of a potent cold front. Lake effect snow has already begun
as a result, but generally terminals should not be impacted
until tomorrow morning when the bands shift southward. Latest
satellite imagery indicates some pockets of clearing that will
eventually expand to break up ceilings for brief times late this
evening. However, with moisture continually streaming into the
region off the Lakes, breaks in ceilings will not be long
lasting.

VFR conditions should remain consistent, however, through much
of the 18z TAF period outside of any snow showers that drift
into terminal boundaries and force MVFR to IFR conditions. KGFL
looks to be the first to be potentially impacted tonight, but
confidence is not high on whether the band will reach far enough
eastward into the terminal. Therefore, a PROB30 group was added
for those aforementioned MVFR conditions. Greater, though still
only low to moderate, confidence exists in KGFL/KALB/KPSF seeing
snow showers tomorrow morning into early tomorrow afternoon as
the primary lake effect band and surrounding showers drift
southward. Here, IFR conditions are more likely, especially for
KPSF where upslope flow will enhance snowfall. Additional
details will be provided as confidence increases with future
iterations. Winds throughout the period will be breezy out of
the southwest with sustained speeds ranging from about 10 to 15
kt with gusts of 20 to 25 kt.

Outlook...

Friday Night: Low Operational Impact. Breezy. Slight Chance of SHSN.
Saturday: Low Operational Impact. Breezy. NO SIG WX.
Saturday Night: Low Operational Impact. Slight Chance of SHSN.
Sunday: High Operational Impact. Definite SHRA...SHSN.
Sunday Night: Moderate Operational Impact. Chance of SHRA.
Monday: No Operational Impact. NO SIG WX.
Monday Night: Low Operational Impact. Slight Chance of SN.
Tuesday: High Operational Impact. Likely SN.

&&

.ALY WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...Winter Weather Advisory from 10 AM to 10 PM EST Friday for
     NYZ054.
     Lake Effect Snow Warning until 1 AM EST Saturday for NYZ032-
     033.
     Lake Effect Snow Warning from 1 AM Friday to 7 AM EST Saturday
     for NYZ038.
     Winter Weather Advisory from 1 AM Friday to 7 AM EST Saturday
     for NYZ039-040-047-082.
MA...Winter Weather Advisory from 10 AM to 10 PM EST Friday for
     MAZ001.
VT...None.

&&

$$

SYNOPSIS...15
SHORT TERM...15
LONG TERM...15
AVIATION...37