187
FXUS61 KALY 250228
AFDALY

AREA FORECAST DISCUSSION
National Weather Service Albany NY
928 PM EST Sun Nov 24 2024

.SYNOPSIS...
Wind will gradually subside tonight with lake-effect rain and
high elevation snow showers also ending. High pressure will
bring fair and seasonable weather on Monday before another
system brings a widespread rainfall Monday night through
Tuesday. Lake effect snow showers will then develop, mainly
across the Adirondacks, later Tuesday through midweek.

&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
.UPDATE...As of 925 PM EST, remnant band of lake effect snow
showers (sprinkles in valleys) across southern Greene County
continues to settle southward and weaken as inversion heights
drop. Patchy clouds will likely continue across southern
Herkimer County, Schoharie County and the SE Catskills with some
extensions into the mid Hudson Valley/NW CT over the next
several hours, while breaks continue to expand within the Hudson
River Valley from Albany north.

Gusty west to northwest winds persist, with some gusts of 20-30
mph across the Berkshires. These gusty winds will continue for
another several hours before gradually decreasing toward and
after midnight.

Temps range from upper 20s/lower 30s across higher terrain of
the SW Adirondacks, to the mid 30s to lower 40s elsewhere. Temps
will fall off more rapidly after midnight once winds gradually
subside and some clearing occurs.

[PREVIOUS 328 PM EST]...High pressure and weak upper level
ridging will build into the region tonight which will allow for
winds to gradually subside and bring an end to any remaining
lake- effect rain/snow shower activity. The arrival of drier air
will also result in a trend toward a partly to mostly clear
sky. There should be enough of a surface wind in place to
prevent widespread radiational cooling potential, but any areas
that do decouple could fall a few degrees lower than current
forecast lows. Generally, lows should fall back into the 20s to
lower 30s.

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH TUESDAY NIGHT/...
Weak upper level ridging and surface high pressure will bring a
dry and seasonable day on Monday with less wind compared to
this weekend. Some high clouds will begin to increase later in
the day as our next system approaches. Highs will reach the 40s
to lower 50s with some upper 30s across the Adirondacks and
southern Greens.

Clouds will continue to increase and thicken Monday night as low
pressure tracks across the Great Lakes bringing a warm/cold
front across the region. Temperatures could fall quickly Monday
evening if there remains enough clearing due in part to light to
calm winds. Forcing from a negatively-tilted shortwave will
result in periods of rainfall overnight and through the day
Tuesday. The arrival of warmer air should result in
precipitation being rain for most areas. However, where low-
level cold air remains trapped, some pockets of freezing rain
could occur before transitioning to plain rain. Areas favored
for freezing rain still look to be portions of the Adirondacks
into southern Vermont but again will depend on surface
temperatures. If any freezing rain were to occur, amounts do
not look to be any more than a light glaze (less than 0.10 of an
inch flat ice). Will continue to mention this possibility in
the HWO.

Rain tapers off in the afternoon behind the cold front. Lake-
effect rain/snow showers will then develop later Tuesday
afternoon and continue through Tuesday night with westerly flow
favoring the Adirondacks where a few inches of snowfall
accumulation could occur by Tuesday night.

High temperatures will reach the 40s to lower 50s on Tuesday
with lows falling back into the mid-20s to mid-30s Tuesday
night.

&&

.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
Lake-effect showers will continue on Wednesday across the
Adirondacks but gradually taper off and lift northward out of
the area throughout the day as flow turns more southwesterly.
There still remains very large spread with respect to potential
impacts, if any, from a storm system Thanksgiving Day into
Friday. The overall track of this system will depend on the
phasing (or lack thereof) of northern and southern stream
shortwaves approaching from the western US/southwestern Canada
this week. These features have not been sampled well as of yet
resulting in large spread in overall guidance. The GFS/CMC
deterministic and ensembles show less phasing and a weaker,
more southern track which may just graze portions of our area
(mainly our southern half) with a mix of rain and snow.
However, the ECMWF deterministic/ensembles are clustered to more
phasing and a more northern storm track resulting in more
widespread precipitation but still mainly in the form of
rain/snow. Given the continued uncertainty, will hold PoPs in
the chance to low likely range with the higher PoPs in southern
areas. Regardless of the track, thermal profiles suggest that
precipitation would favor rain and less snow in valleys areas
with higher snow probabilities across the higher elevations.
Will continue to monitor throughout the week. In the wake of
this system confidence is high (greater than 70%) for a period
of below normal temperatures post Thanksgiving Day through next
weekend with lake-effect snow showers downwind of the Great
Lakes.

&&

.AVIATION /03Z MONDAY THROUGH FRIDAY/...
Through 00Z/Tue...Some lake effect sprinkles at KALB, and
sprinkles/flurries at KPSF should diminish between 01Z-02Z/Mon,
otherwise dry through the end of the TAF period. Occasional MVFR
Cigs this evening at KALB and especially KPSF, becoming VFR
after midnight and then prevailing through Monday. Winds will
be west to northwest at 8-15 KT with some gusts up to 25 KT
this evening, with some gusts up to 30 KT possible at KPSF.
Winds will decrease to 5-10 KT after midnight from the west to
northwest although some gusts up to 20 KT could linger until
daybreak at KPSF. On Monday, winds will be from the west at 8-12
KT then decreasing to less than 8 KT by late afternoon.

Outlook...

Monday Night: High Operational Impact. Likely RA.
Tuesday: High Operational Impact. Definite SHRA...RA.
Tuesday Night: No Operational Impact. NO SIG WX.
Wednesday: Low Operational Impact. Breezy. NO SIG WX.
Wednesday Night: Low Operational Impact. Slight Chance of RA.
Thanksgiving Day: Moderate Operational Impact. Chance of RA.
Thursday Night: Moderate Operational Impact. Chance of RA...SN.
Friday: Moderate Operational Impact. Chance of RA...SN.

&&

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

&&

$$

SYNOPSIS...Rathbun
NEAR TERM...KL/Rathbun
SHORT TERM...Rathbun
LONG TERM...Rathbun
AVIATION...KL