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fxus61 kaly 171158 
afdaly

Area forecast discussion
National Weather Service Albany New York
658 am EST sun Nov 17 2019

Synopsis...
dry and cold conditions will continue through today as high
pressure moves east across southeastern Canada and northern New
England. A coastal storm is expected to bring some freezing
rain, sleet and rain to eastern New York and western New England
late tonight into Monday. Unsettled weather continues into the
middle of the week as upper level disturbances may bring
additional wintry precipitation Monday night and Tuesday night.

&&

Near term /until 6 PM this evening/...
as of 650 am, stratus have quickly expanded into the Mid-Hudson
valley and portions of the eastern Catskills faster than
anticipated. It appears these clouds are not making much
northward progress, but have updated the forecast to reflect
mostly cloudy conditions persisting today where it's cloudy now.
Elsewhere, maintained mainly sunny skies for most of the day.
Otherwise, updated temps to reflect current conditions which saw
many places not drop as much as previously thought.

Previous discussion...

As of 400 am EST...very cold temperatures in place across the
region early this morning. Single digits and 10s are common,
with even some below zero readings in parts of the Adirondacks.
Skies are mainly clear, although some high level cirrus clouds
are passing through the northern half of the area. Today will be
another dry and cold day, with high pressure over northern New
England still influencing our weather. Clouds will gradually
increase across southern portions of the area late this morning
into the afternoon, associated with a developing coastal storm
east of the Carolinas. High temperatures will still be around
10-15 degrees below normal, with mainly 30s forecast.

&&

Short term /6 PM this evening through Tuesday/...
Winter Weather Advisory for freezing rain in effect from 1 am
to noon Monday for much of eastern New York and western New
England.

Cold/dry air mass initially in place this evening, as clouds
continue to increase ahead of the coastal cyclone tracking
northward off the mid Atlantic coast. Moisture from this system
is expected to move into our area late tonight into Monday
morning. With cold air entrenched at the surface and warmer air
moving in aloft, there is the potential for some light icing due
to freezing rain. Global and hi-res model guidance generally
indicating only patchy/spotty light precip during this time.
However, due to below freezing surface temperatures even a trace
could result in a glaze of ice on untreated surfaces. Therefore
we have issued a Winter Weather Advisory for much of the area
except for the western Adirondacks and Lake George area, where
confidence is lower due to being on the edge of where precip is
expected to fall and slightly colder thermal profiles which
could result in more sleet than freezing rain. It is possible
for the advisory to be expanded if confidence for freezing
rain/icing increases in this area. Again, any freezing
rain/drizzle will be patchy, but could cause hazardous travel
conditions during the Monday morning commute.

Will have the initial Winter Weather Advisory expire at noon
Monday, as surface temperatures warm to above freezing during
the morning, changing any freezing rain/sleet to plain rain
across much of the advisory area. Some isolated pockets of
freezing rain could still linger in sheltered higher elevation
locations Monday afternoon.

There is some model consensus for steadier precip to move in
late Monday into Monday night, as an upstream upper level trough
approaches from the South/West and interacts with the coastal
system. By this time, thermal profiles will start to cool, but
there will still be the potential for freezing rain into Monday
evening especially over the higher terrain. A trend to more of
sleet/snow is expected as the night progresses and temps aloft
cool. Additional Winter Weather Advisory may be needed in some
areas Monday evening into Monday night if confidence in freezing
rain increases. This is a challenging forecast due to
transitioning precip types and uncertain timing in these
transitions. Light accumulations of sleet and snow are possible
late Monday night into Tuesday morning associated with the upper
trough, with generally less than an inch. The threat of
freezing rain should be done well before the Tuesday morning
commute.

Rain/snow will gradually end from southwest to northeast across
the area Tuesday morning, as the upper trough pulls away into
northern New England. Some minor snow accumulation will be
possible north of Albany, but should not cause much impact given
expected temperatures warming into the 30s before precip ends.
Some breaks in the clouds may develop from around Albany
southward Tuesday afternoon.

&&

Long term /Tuesday night through Saturday/...
Tuesday night into Wednesday, models depict a midlevel trough
sliding into the northeast states from the upper Great Lakes.
Moisture and lift do not look to be too strong with this system,
so pops are confined to the higher terrain west of the Hudson
where there may be some lake moisture contribution. Heights rise
in the wake of this system Wednesday night into Thursday
morning, so this looks to be a dry period with high pressure
nosing in from the south. A low pressure system is forecast to
develop quickly Thursday into Thursday night, crossing the
western Great Lakes into southern Quebec. There is uncertainty
with the strength and timing of this system, but consensus
tracks this system to our northwest, putting our forecast area
in the warm sector. Some precip associated with an increasing
low level jet could begin west of the Hudson by Thursday
afternoon, but highest pops will be Thursday night. Measurable
precip is most likely over the southern Adirondacks where the
low- level jet will favorably intersect the terrain. Elsewhere,
not enough confidence for anything more than chance pops. It
looks like temps aloft will rise above freezing, so p-type looks
to be rain at lower elevations and rain or a wintry mix at
higher elevations. Based on the track of this system, precip
does not look to be too heavy or prolonged. A strong cold front
looks to track through Friday, shutting off the precip except
for across the western Adirondacks where a period of lake effect
snow is possible into Friday night. Early indications for
Saturday are for a cooler and breezy but dry day.

Temperatures during the period look to start out a bit below
normal Wednesday, gradually warming to near normal Thursday and
perhaps into Friday depending on the frontal timing, and then
cooling back below normal by Saturday.

&&

Aviation /12z Sunday through Thursday/...
a ridge of high pressure will remain in place for most of
today, resulting in mainly clear skies aside from a few high
cirrus. However, stratus around 4kft has already expanded over
kpou, and ceilings may persist there for most of the day. A low
pressure system slowly approaching from the south will begin to
send lower clouds toward the terminals from south to north
later this afternoon into the evening. Ceilings may lower to
MVFR after 00z Monday at kpou/kpsf. Best estimate for MVFR
ceilings at kalb is 03z, and not until 09z at kgfl. Some light,
spotty precipitation will be possible mainly after 06z.
Temperature profiles will support freezing rain with anything
that falls at kpsf, while temperatures at the surface at kpou
may be just warm enough for plain rain. Probability of
precipitation is slightly lower, but non-zero, at kalb, so a
prob30 was inserted from 09-12z for freezing rain.

Winds will be mainly from the north to northeast at around 5 to
10 kt through the taf period.

Outlook...

Monday night: high operational impact. Likely rain...sleet.
Tuesday: moderate operational impact. Chance of rain...sn.
Tuesday night: no operational impact. No sig weather.
Wednesday: no operational impact. No sig weather.
Wednesday night: no operational impact. No sig weather.
Thursday: low operational impact. Slight chance of rain showers.

&&

Fire weather...
dry and cold conditions will continue through today as high
pressure moves east across southeastern Canada and northern New
England. A coastal storm is expected to bring some freezing
rain, sleet and rain to eastern New York and western New England
late tonight into Monday. Unsettled weather continues into the
middle of the week as upper level disturbances may bring
additional wintry precipitation Monday night and Tuesday night.

&&

Hydrology...
some minor tidal flooding is possible on the Hudson River in
the vicinity of Poughkeepsie and Kingston on the high tides over
the next couple of days.

Cold and dry conditions are forecast through today. Multiple
periods of precipitation are expected from late tonight through
Friday. Forecast precipitation through the next 7 days ranges
from a half inch in the Mid Hudson valley to around an inch in
the higher terrain, with the highest amounts over the southern
Adirondacks.

With generally light precipitation and some of it frozen, minor
changes in river stages are forecast during the next week.

With the cold temperatures in place, some ice will continue to
form on shallow bodies of water and also on some streams.

For details on specific area rivers and lakes, including latest
observed and forecast river stages and lake elevations, please
visit the advanced hydrologic prediction service /ahps/ graphs
on our website.

&&

Aly watches/warnings/advisories...
CT...Winter Weather Advisory from 1 am to noon EST Monday for
ctz001-013.
New York...Winter Weather Advisory from 1 am to noon EST Monday for
nyz038>041-047>054-058>061-063>066-082>084.
Massachusetts...Winter Weather Advisory from 1 am to noon EST Monday for
maz001-025.
Vermont...Winter Weather Advisory from 1 am to noon EST Monday for
vtz013>015.

&&

$$
Synopsis...jpv/speciale
near term...Thompson/jpv
short term...jpv

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