398
FXUS61 KALY 101136
AFDALY

AREA FORECAST DISCUSSION
National Weather Service Albany NY
636 AM EST Fri Jan 10 2025

.SYNOPSIS...
High pressure will ensure the return to regionwide dry
conditions today with winds continuing to diminish. Widespread
light snow is anticipated for the beginning of the weekend
before another brief period of tranquility Sunday into at least
Monday morning before additional chances for snow showers,
mainly for higher elevations, come through the middle of the
workweek.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Key Message:

- Winds continue to decrease throughout the day with dry
  conditions in place across the region.

Discussion:

.UPDATE...As of 635 AM EST...The forecast remains in good shape
with this update with primarily minor updates to reflect latest
obs. Made some adjustments to the prevailing winds and gusts for
the next several hours as latest obs indicate speeds remain
elevated across much of our forecast area considering the 850 mb
jet remains 40 to almost 50 kt from the Capital District south
and 925 mb winds aren`t far below at 35 to 40 kt. Model
soundings indicate potential mixing up to around 950 mb, so
while we may not be tapping into the strongest winds aloft, the
persistent west-northwest to northwest direction has continued
to support downsloping to keep speeds elevated amid a slackening
pressure gradient. Otherwise, all else remains unchanged with
additional details following in the previous discussion below.

.PREVIOUS DISCUSSION [407 AM EST]...
After a blustery couple of days, winds will gradually continue
to dwindle throughout the day as the antecedent pressure
gradient across the region slackens in the face of an advancing
surface anticyclone and attendant upper-level ridge. That said,
it has continued to be gustier than previously thought overnight
with frequent gusts of 20 to 40 mph seen within the Mohawk
Valley, Capital District, Helderbergs, Taconics, and Berkshires.
According to the latest SPC Mesoanalysis, the aforementioned
pressure gradient remains fairly tight, though it has weakened
in comparison to yesterday. Additionally, west-northwest winds
seem to be supporting a persistent downsloping effect coupled
with channeling down the Mohawk and portions of the Hudson
Valley. But with our impending high pressure ridge cresting over
the Eastern Great Lakes and the northern reaches of the
associated surface high stretching into western New York, it is
anticipated that wind will continue along a downward trend
through the next several hours and into the rest of the day.

Accompanying the calming winds throughout the day today will be
regionwide dry conditions. Increase subsidence induced by the
building of the surface high and eventual crest of the upper
ridge will lead to erosion of current cloud cover and
consequently partly cloudy to mainly clear skies. That is, at
least until later this afternoon when the ridge begins to shift
east, allowing high clouds to begin streaming into the region
ahead of an approaching northern-stream shortwave.

Currently, temperatures range from the mid/upper 10s to mid 20s
with low 10s at elevations exceeding 1000 ft. With 850 mb
temperatures warming to ~ -5C to -1C today, high temperatures
will be several degrees warmer than recent days. And, with
decreasing wind speeds, highs will feel much more tolerable
given the lack of a harsh wind chill. That said, temperatures
will reach the mid/upper 20s to low 30s with pockets of upper
10s to low 20s at higher elevations and mid 30s in the Mid-
Hudson Valley.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/...
Key Message:

- Widespread snow showers Friday night through Saturday will
  lead to light accumulations of ~0.5" to 1.5" and locally
  higher amounts closer to 2" in the higher elevations of the
  Southern Adirondacks and Southern Greens.

Discussion:

Clouds continue to increase throughout the evening and overnight
period tonight as our surface high and upper ridge weaken and
shift east and a northern stream shortwave deepens upstream. As
this feature nears, a weak surface low will develop and move
into the northern Great Lakes region with an eventual coastal
low taking shape well to our south near the Carolinas. While
this southern disturbance will remain well to our south, newly
developed southerly flow across our region will advect warm,
moist air northward to allow a weak area of isentropic lift to
lift into southern zones. This and upslope flow along south-
facing slopes of the Eastern Catskills will aid in overcoming
substantial low-level dry air shown on latest forecast soundings
and likely contribute to snow beginning to fall in the Eastern
Catskills first. Elsewhere, model soundings also show
significant low-level dry air which will impede snow reaching
the ground in the early stages of onset. However, as cyclonic
vorticity advection increases with the progress of the shortwave
trough, forcing for ascent, in addition to any ongoing virga, will
help to further moisten the column and allow light showers to
reach the surface regionwide by early Saturday morning. Low
temperatures tonight will fall to the 10s to low 20s.

Light showers will continue throughout the day Saturday as the
shortwave continues its rotation through the Northeast, becoming
somewhat closed off over eastern New York and New England by
Saturday afternoon. High temperatures Saturday will reach the
20s to low 30s. As this is a fairly progressive disturbance,
the closed low and associated shortwave looks to shift off to
our east by late Saturday evening, yielding modest height rises
in its wake as another high pressure ridge builds in across the
Northeast. Low temperatures Saturday night will fall to the
mid/upper 10s to low 20s. Dry conditions will then be
reinforced for the end of the weekend with highs reaching the
20s to low/mid 30s. Lows Sunday night will then fall widely to
the mid/upper 10s with isolated pockets of low 20s mainly in the
Mid-Hudson Valley.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
Key Message:

- Lake effect snow expected in the western Adirondacks Monday night
through Tuesday, with a light to moderate accumulation.

- Temperatures trending colder through next week, with high
confidence in below normal precipitation persisting.

Discussion:

A clipper system is expected to track east across southern
Ontario/Quebec into northern Maine Mon into Tue. Heights aloft will
fall late Mon into Mon night, bringing scattered snow showers mainly
to areas north/west of Albany. By Tue, cooling aloft along with
westerly winds strengthening and becoming well-aligned will likely
allow for lake effect snow to develop downwind of Lake Ontario into
the W. Adirondacks. NBM probs indicating 60-90% chance for at least
1" of snow, but only 20-40% for > 4" in this area. The probs assume
a 10:1 SLR, so amounts could exceed these thresholds but snowfall
still doesn`t look overly heavy especially due to short residence
time around 12 hours or less, with light to moderate accumulations
possible.

Lake effect snow should be short-lived, as the system`s upper level
low tracks SE across our area Tue evening, which will shift winds to
a NW direction, resulting in lake effect snow bands weakening and
shifting south into the Mohawk Valley Tue night and eventually west
of our area into central NY by Wed. With a cyclonic NW flow
persisting through Thu, upslope snow showers may occur into the W.
Adirondacks, with mainly dry conditions expected elsewhere.
Temperatures will trend slightly cooler each day through Thu, as the
upper trough settles in with breezy NW winds.

&&

.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
Through 12z Saturday...Northwest flow persists through this morning,
with plenty of upslope clouds at KPSF but also occasionally backing
up into the Hudson Valley at KALB. VFR cigs at KALB with solid MVFR
cigs at KPSF lingering through around 14z-15z. Mainly FEW-SCT clouds
expected at KPOU/KGFL. Lower level clouds should finally scour out
later this morning as high pressure builds in from the west. High
level clouds will increase this evening, lowering to mid level cigs
(still at VFR levels) around 06z Saturday. Light snow and MVFR
conditions are expected to begin just prior to 12z, as a disturbance
approaches from the west.

Winds will be northwest around 5-15 kt with gusts of 20-25 kt
persisting at KALB/KPSF through through much of the morning. Winds
the rest of the day will be north-northwest around 6-12 kt. Winds
become variable at less than 5 kt tonight.

Outlook...

Saturday Night: No Operational Impact. NO SIG WX.
Sunday: No Operational Impact. NO SIG WX.
Sunday Night: No Operational Impact. NO SIG WX.
Monday: No Operational Impact. NO SIG WX.
Monday Night: No Operational Impact. Slight Chance of SHSN.
Tuesday: Low Operational Impact. Breezy. Slight Chance of SHSN.
Tuesday Night: No Operational Impact. NO SIG WX.
Wednesday: Low Operational Impact. Breezy. NO SIG WX.

&&

.ALY WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
MA...None.
VT...None.

&&

$$

SYNOPSIS...Gant
NEAR TERM...Gant
SHORT TERM...Gant
LONG TERM...JPV
AVIATION...JPV