990
FXUS61 KALY 221634
AFDALY

AREA FORECAST DISCUSSION
National Weather Service Albany NY
1134 AM EST Fri Nov 22 2024

.SYNOPSIS...
Widespread valley rain and mountain snow this morning
tapers to rain and snow showers this afternoon and evening, with
several inches of accumulation for the high terrain areas west of
interstate 87 by the time the storm winds down. Scattered light rain
and snow showers continue on and off through the weekend with cool
and breezy conditions. After a brief break Monday, precipitation
chances look to increase again for Tuesday.

&&

.NEAR TERM /THROUGH TONIGHT/...
Winter Storm Warning in effect for western Greene and western
Ulster counties until 1 AM Saturday for elevations mainly above
1500 feet.

Winter Weather Advisory in effect for Schoharie County until 1
AM Saturday for elevations mainly above 1000 feet.

.Update...As of 11:15 AM, a chilly and damp Friday continues as
our mature/occluded surface meanders over the eastern Catskills
and temperatures remain in the mid-30s to low-40s. The cold
conveyor belt and enhanced FGEN in the mid- levels has resulted
in a organized band of precipitation across the southern Tier
and central NY. As the cold conveyor belt wraps into the east
side of the surface low this afternoon, this band will track
into eastern NY providing another period of more organized
valley rain and wet snow for elevations at and above 1000 feet.
The eastern and northern Catskills will likely be most impacted
with wet snow accumulations and potential snowfall rates at or
above 0.5"/hr leading to an additional 1 to 4 inches with 3 to 6
inches for areas above 2000 feet. Additional power outages for
these higher terrain areas is possible given the wet snow that
has already accumulated plus the additional snow this afternoon.
Considered issuing a winter weather advisory for western Albany
County but given the long duration of this event and the fact
that the highest totals will around and above 1500ft, decided to
hold off and will instead issue a Special Weather Statement
once the band develops this afternoon. Snowfall rates

Based on latest NYS mesonet obs and ground truth data, highest
snowfall totals so far have occurred in the eastern Catskills
for elevators around and above 2000 feet where reports range
from 10 to 14 inches with a respectable 10 to 12 inches in the
higher terrain areas of Schoharie County. Even western Albany
County in elevations above 1000 feet have received 2 to 5
inches of wet snow.

Previous discussion...Rain and snow showers diminish in
coverage this evening as the surface and upper low track in
tandem to our south off the NJ coast. A shortwave rotating
around the periphery of the upper low will help to induce
surface cyclogenesis off the coast of Cape Cod, and while this
storm will track towards Maine and Nova Scotia, some rain/snow
showers in its precip shield could spread back into western
MA/VT as an inverted trough develops back towards the core of
the upper low. Additional light snow accumulations will thus be
possible in the southern Greens tonight. Given that the snow
will be relegated to the mountains, we did not consider adding
this area to the advisory, although a few of the mountain towns
could see snow totals of 3-6" between this mornings snow and the
additional snow showers tonight. Lows tonight will be mainly in
the 20s to 30s.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY/...
Saturday and Sunday...The upper low will track off the New
England coast Saturday, becoming centered over Nova Scotia by
Sunday. A second upper shortwave will track from the northern
Great Lakes and through upstate NY Sunday, becoming absorbed
into the upper low. Thus, with our proximity to the upper low
and moist cyclonic flow aloft, we will likely see some scattered
rain/snow showers on Saturday, especially in the NW flow
upslope favored areas and downwind of the Great Lakes where some
lake effect/enhanced snow showers are expected. With NW flow
trajectories and enhanced lift by the approaching shortwave, a
band of lake effect snow looks to reach the northern Catskills
and potentially southwestern Mohawk Valley Saturday night into
Sunday morning, with additional light accumulations of snow
possible. However, the trend through the day Sunday should be
for drier conditions by the afternoon. Both Saturday and Sunday
will feature gusty northwest winds and highs in the 30s to 40s.
Lows Saturday night will be in the 20s to 30 again.

&&

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

- Active long term with several chances of precipitation

Discussion:

High pressure will build across the region Sunday night into the
daytime Monday, and should give us a brief break in precipitation
chances before the arrival of our next weather maker Monday night.
Morning lows in the 20s to near 30 will quickly rise into the upper
40s to low 50s with a warm front lifting in from the south.
Increased lift along the front with a trailing shortwave will
increase precipitation chances, especially north of the Mid Hudson
Valley. Rain is favored, though some wet snow may mix in at higher
elevations late Tuesday as flow switches back to the west/northwest
with a cold front. Much cooler air will follow with lows back into
the 20s to low 30s Tuesday night, and highs ranging from the upper
20s/low 30s (terrain) to mid 40s (valleys) Wednesday.

Most will see dry weather for the middle of next week, though some
lake effect/upslope rain and snow showers will be possible across
the Mohawk Valley and western ADKs Wednesday. Will need to keep an
eye on the Thanksgiving holiday as some guidance continues to
suggest potential for another system to track over or just near the
region. With confidence on the system track and timing still low
this far out, will continue to advertise low chance (20-40%) POPs at
this time. Temperatures look to average below normal for the end of
November.

&&

.AVIATION /16Z FRIDAY THROUGH TUESDAY/...
Through 12z Saturday...Poor flying conditions will persist across
the region through the upcoming TAF period, as a complex storm
system continues to slowly track across the region. Conditions will
generally be MVFR to IFR, especially in areas of rain and snow where
ceilings and visibilities will be reduced. Snow is favored initially
at KPOU, but will mix with and change to rain by mid morning as
temperatures rise. Activity will taper off late this afternoon and
evening, though VCSH mentions have been maintained with lingering
rain showers. An additional band of rain and snow is possible late
in the period, and has been accounted for with a new PROB30 group in
this TAF.

Winds will vary initially due to the position of the surface low
pressure, but should shift to the east around 5-15 kts with gusts
around 20-25 kts by late morning. By late this afternoon and
evening, winds will decrease to around 5-10 kts out of the
north.

Outlook...

Saturday Night: Low Operational Impact. Breezy. Slight Chance of SHRA.
Sunday: Moderate Operational Impact. Windy With Gusts To 31 kts. NO SIG WX.
Sunday Night: No Operational Impact. NO SIG WX.
Monday: No Operational Impact. NO SIG WX.
Monday Night: High Operational Impact. Likely SHRA.
Tuesday: Moderate Operational Impact. Breezy. Chance of SHRA.
Tuesday Night: No Operational Impact. NO SIG WX.
Wednesday: Low Operational Impact. Breezy. NO SIG WX.

&&

.ALY WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...Winter Weather Advisory until 1 AM EST Saturday for NYZ047.
     Winter Storm Warning until 1 AM EST Saturday for NYZ058-063.
MA...None.
VT...None.

&&

$$

SYNOPSIS...Main/Speciale
NEAR TERM...Main/Speciale
SHORT TERM...Main
LONG TERM...Speck
AVIATION...Speck