NWS ALY
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SATURDAY NIGHT/...
Winter Storm Watch for the southern Adirondacks of northern
Herkimer, Hamilton, northern Warren, and northern Fulton
Counties from 1 AM EST SAT to 7 AM EST SUN....
Winter Storm Watch for elevations 1500 feet or greater in
Bennington and western Windham Counties from 1 AM EST SAT to 7
AM EST SUN...
Tomorrow...The mid and upper level ridge will only hold briefly
over NY and New England. The ridge will break down and move
down stream. The H500 cutoff low moves over the Midwest. A deep
fetch of Gulf of Mexico moisture will occur ahead of the warm
front to the system. The trend with the EC/NAM/GFS/CMC and
Ensembles is to hold off for the warm advection pcpn until night
fall. The clouds may thin early in the day a bit, but then
thicken and lower by nightfall. The low-level jet will also
begin to crank-up late. The boundary layer east to southeast
flow increases. Expect east to southeast winds to 5 to 15 mph
during the day. Max temps will reach the upper 30s to lower 40s
in the valleys with the influx of slightly milder air beginning,
and upper 20s to mid 30s over the mtns.
The guidance continues to form the secondary low a bit further
inland than previous days. The NAM has the sfc wave moving from
NJ to near NYC by daybreak Saturday. The 12Z GFS is slightly
further west over northeast PA into southern NY and the EC/CMC
takes the secondary low over central/eastern Long Island.
The column should be warm enough for mostly rain in the
valleys. The southern Adirondacks and southern Greens may hold
as snow for a time. The eastern Catskills may have some snow/mix
to rain. The western Mohawk Valley/Upper Hudson Valley may have
some brief snow before changing to rain.
However, temps should be rising overnight with lows in the
upper 20s to lower 30s over the mtns, and lower to upper 30s in
the valleys. We started the Winter Storm Watch at 06Z/SAT for
the southern Adirondacks and southern Greens focusing on a
window of 12hrs for wet snow during the the stretch in Sunday
morning for 7" snow in 12 hours in the southern Adirondacks, and
6"/12 hrs for elevations above 1500 ft in southern VT. 9" in 24
hours is needed for all locations in the Winter Storm Watch.
Other locations may need advisories Fri night into Saturday such
as the eastern Catskills and Helderbergs when colder air will
filter back in as the secondary low lift north/northwest across
the region.
The sfc winds will increase over the western New England higher
terrain from the east to southeast with winds of 15 to 25 mph
with some gusts in the 35-45 mph range. We will have to monitor
for a possible Wind Advisory if greater gusts are expected off
the southern Greens. Temps should be rising into the 30s to
lower 40s by day break.
Sat-Sat night...It is a quick system with the majority of the
pcpn falling in 9-12 hrs. The dry slot will begin to punch in
during the late morning into the afternoon. The pcpn should
transition back to snow especially west of the Hudson River
Valley by the afternoon as colder air filters back in. By the
late morning into the afternoon temps should peak and start to
fall. Additional snow amounts of a few inches are possible in
the afternoon especially over the higher terrain west of I-87.
The winds should switch to the west to southwest. Highs on SAT
could be in the upper 30s to mid 40s from the Hudson River
Valley and Lake George eastward into western New England, and
30s to the west.
The synoptic event diminishes SAT night with wrap around, lake
enhanced and upslope snowfall beginning. We tried to collaborate
with WFO BTV and BUF, as they we keeping neighboring watches
going into the subsynoptic time frame. We kept the Watch going
until 12Z SUN, but could reach the snow criteria for warning
level snows prior to this change. The snow levels will lower and
and some light snow accumulations are possible over the hill
towns possibly into the valleys. It will be brisk and colder
with lows in the 20s to around 30F.