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fxus61 kaly 241146 
afdaly

Area forecast discussion
National Weather Service Albany New York
646 am EST Wed Jan 24 2018

Synopsis...
a cold front will continue to move east of New England
this morning. In the wake of the cold front, much colder air will
return with brisk conditions today into tonight. Tranquil weather
conditions with below normal temperatures will continue into
Thursday, as high pressure will ridge in across the region to close
the work week.

&&

Near term /until 6 PM this evening/...
as of 646 am EST...a secondary cold front continues to push
east to southeast across western New England this morning. The
mid and upper level trough associated with cyclone yesterday is
also lifting northeast across northern New England and southeast
Quebec. The threat for the potential of additional flooding has
diminished, and the Flood Watch was canceled. Received some
reports of black ice in Litchfield County from media, so have
issued an Special Weather Statement for all of western New England until 9 am for some
slick roads,sidewalks, etc. On the untreated surfaces. Some
minor retooling of pops and T/dew point trends with mins just being
achieved with cold advection.

Strong cold advection is occurring across the forecast area.
Temps continue to falling into the teens to lower 30s, as the
winds shift to the west to northwest at 10-20 mph with some
gusts in the 30-40 mph range especially in the Mohawk
Valley/capital region/ northern-central Taconics and Berkshires.

BUFKIT profiles show the potential for some gusts close to 35
kts for kalb/kpsf if we mix to 2 kft above ground level. The strong low-level
horizontal pressure gradient between the departing cyclone into
the Canadian Maritimes and high pressure building in from
south-central Ontario will keep it brisk during the morning into
the afternoon. In the cold advection regime, h850 temps lower
to -10c to -13c from the capital region south and east and -13c
to -17c north and west.

Diffuse snow shower and flurry activity will continue downstream
of Lake Ontario over the western Adirondacks/Mohawk
Valley/northern Catskills/Schoharie valley. Some westerly
orographic enhancement is possible this morning over the
northern Taconics/Berkshires/southern greens. Additional light
snow accums of an inch or two are possible over the western
Adirondacks and an inch or so in the western Mohawk Valley.
Elsewhere coatings to a half an inch are possible.

The snow shower coverage will shrivel in the mid to late
afternoon with the subsidence inversion lowering and the flow
veering to the northwest with narrow multibands favored west of
the forecast area. High temps will be in the morning to around
noontime with downsloping occurring in the Hudson Valley.
Expect highs in the upper 20s to mid 30s in the valley areas and
hilltowns, and upper teens to mid 20s over the mtns. Temps will
lower over fall off a few degs in the afternoon.

&&

Short term /6 PM this evening through Friday night/...
tonight...clearing skies and the winds will slacken slightly
with high pressure building in from southeast Ontario and north
of Georgian Bay. Wind chills may get into the 5 to 15 below zero
range over the southern Adirondacks and west-central Mohawk
Valley. As low temps fall into the single digits and to 5 below
zero north and west of the capital district, and teens from the
Tri Cities south and east.

Thu-Thu night...cyclonic flow continues aloft over New York and New
England, as roughly a 1030-1035 hpa sfc anticyclone continues
to build in. This Arctic high will yield a chilly day with high
temps 5 to 7 degrees below normal. Party to mostly sunny skies
are expected due to the strong subsidence with the anticyclone.
Highs will be in the 20s, except across the southern
Adirondacks, and southern greens will be in the teens, with a
few lower 30s in the Mid-Hudson valley. A frigid night is
expected with light to calm winds as the high settles in over
the region. Lows will be in the single digits, except for a few
below zero readings over the Adirondack park, and a few lower
teens in the Mid Hudson valley.

Fri-Fri night...the tranquil late Jan weather continues. The
sfc high slides slowly east of the region and dominates along
the East Coast. Mid and upper level heights begin to rise
upstream of the Hudson River valley. Temps moderate to seasonal
levels with warm advection beginning Fri night as a 1038 hpa or
so sfc anticyclone builds in from off the southeast New England
coast. A cold front will be slowly approaching from Great Lakes
region, and the MS River Valley for the weekend. Temps will
trend closer to normal to end the work week.

&&

Long term /Saturday through Tuesday/...
the period starts out on Saturday with surface high pressure well
off the East Coast and a Flat Ridge aloft across the region. A south-
southwest flow should lead to decent warming despite clouds
increasing during the day. Models have come into better agreement
indicating a subtle frontal boundary moving in by late in the day.
This will result in chance for some showers. Expecting the precip to
be mainly rain on Saturday, supported by expected surface
temperatures in the upper 30s to upper 40s. The boundary is expected
to become stationary over the region Saturday night, although the
pattern looks to be less amplified compared to previous model runs
so only light quantitative precipitation forecast is expected then. Some snow may mix with rain
across higher terrain areas, but will mention mainly rain for valley
locations.

A weak wave of low pressure is forecast to develop along the stalled
front in the Ohio Valley region Saturday night, and move across our
area on Sunday. This is when the highest pops are forecast. There
are some model differences, mainly with timing of the wave. Quantitative precipitation forecast
amounts look to be light to moderate at this time, again with a less
amplified pattern overall. Thermal profiles look borderline for
rain/snow in the mountains north of Albany, with plain rain
elsewhere. As the front and wave of low pressure start to pull away
Sunday night, rain may change to snow before tapering off to
scattered snow showers. The best chance for some accumulating snow
will be over the higher terrain and especially north of Albany.
Specifics still could change considerably based on the eventual
position of the front and track of the surface wave since this event
is still 4-5 days out.

A cyclonic northwest flow regime within a large scale upper trough
should develop in wake of the weekend system, with lake enhanced and
upslope snow showers across the region early next week. Temperatures
will cool back down to normal levels for late January by Monday
night into Tuesday.

&&

Aviation /12z Wednesday through Sunday/...
a cyclonic northwest flow will continue to result in plenty of
stratocumulus clouds today, with cigs mainly in VFR range, although
MVFR cigs will be common at kpsf through much of the morning with
occasional MVFR cigs at kalb too. Clouds will tend to become more
scattered by later today as the flow becomes more neutral with
surface high pressure approaching from the Great Lakes. An upper
level disturbance passing by to our south tonight will result in
increasing mid-level clouds well into the VFR range.

Winds will be northwest today around 12-17 kt with gusts of 20-30
kt. Winds speeds will decrease to around 10 kt or less later this
evening.

Outlook...

Thursday night: no operational impact. No sig weather.
Friday: no operational impact. No sig weather.
Friday night: no operational impact. No sig weather.
Saturday: low operational impact. Slight chance of rain showers.
Saturday night: moderate operational impact. Likely rain showers.
Sunday: high operational impact. Likely rain.

&&

Hydrology...
the Flood Watch has been canceled. A few flood warnings remain
up for flooding related to snow melt, runoff and ice jams. They
are in Warren and Rensselaer counties, and also for the
Housatonic River near Kent. Please see the warnings for details.

Within bank rises occurred on many main Stem rivers from the
half an inch to inch and a half of rainfall that occurred
yesterday coupled with some snow melt. The rivers have crested
and will gradually receded today.

A much colder and more seasonable airmass today into Friday
will continue to allow flows to lower. Ice will continue to a
problem on many rivers, and the colder temps will allow more
thickening and reformation.

Milder air and another round of rainfall are expected over the
weekend which could be lead to renewed concerns for flooding
especially in the vicinity of ice jams. However, there is a lot
of uncertainty on the amount of quantitative precipitation forecast with the next system late
in the weekend, and some of the ptype could be snow.

For details on specific area rivers and lakes, including 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...none.
New York...none.
Massachusetts...none.
Vermont...none.

&&

$$
Synopsis...wasula

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