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fxus61 kaly 171442 
afdaly

Area forecast discussion
National Weather Service Albany New York
942 am EST Wed Jan 17 2018

Synopsis...
a low pressure system positioned just off the Delmarva early
this morning, will track northeast to near Cape Cod by this
afternoon. This system continues to bring a moderate to heavy
snowfall to much of the region. The system will move into the
Canadian Maritimes this evening, with snow ending across our
area during the afternoon. Seasonably cold and mainly dry
weather is expected tonight through Thursday, with some lake
effect snow showers across the western Adirondacks.

&&

Near term /until 6 PM this evening/...
as of 930 am EST, still areas of light to moderate snow across
the region, with steadiest snow currently in a band extending
from northern Schoharie County into the east central Mohawk
Valley, northeast across the Saratoga/Glens Falls region.
Snowfall rates of up to an inch/hour will be likely within this
band. Elsewhere, snowfall rates generally range from one tenth,
to up to one half inch/hour.

Based on current radar, and also some prospects for additional
snowfall close to the capital region due to some possible
Mohawk-Hudson convergence, still expect an additional 1-3 inches
from the east central Mohawk Valley northeast to The Glens
falls/Saratoga region, southeast into the capital region, with
mainly less than 2 inches elsewhere.

Across the western Adirondacks, some upslope/lake enhanced snow
could contribute to an additional 1-3 inches, if not locally
higher, across portions of northern Herkimer Colorado through this
afternoon.

Otherwise, through 8 am EST, snowfall accumulations have
varied, with generally 4 to 8 inches for areas south and east of
Albany, and 2 to 5 from Albany north and west. Still a few to
several more hours of light to moderate snow is expected, as the
coastal low pressure system tracks from south of Long Island to
near Cape Cod this morning. Will keep the current headlines in
place without any changes at this time. Lighter snowfall amounts
have been reported in southern Vermont, but snow will continue
through the morning and into early afternoon with time to reach
warning levels.

The steadiest snow is expected to continue through the late
morning. Snow will gradually taper off from west to east late
this morning into early afternoon. However, hints of Hudson-
Mohawk convergence noted in the model surface wind fields and
forecast reflectivity from the 3km NAM/hrrr/WRF-arw from around
Albany north and east. So will linger mention of likely pops in
these areas with an additional half inch to inch of snow this
afternoon. Temperatures will be seasonable for mid January,
ranging from lower 20s in the northwest part of the area to
lower 30s in the southeast.

&&

Short term /6 PM this evening through Friday night/...
a small ridge of high pressure will build in to much of the
region tonight, although well-aligned westerly flow and
conditional lake- induced instability will lead to some lake
effect snow showers across the western Adirondacks. Snow showers
will be light and scattered, due to forecast low inversion
heights of only around 850 mb. Elsewhere, it will be partly
cloudy with temperatures near normal with single digits to lower
teens.

Similar weather expected for Thursday, as a Flat Ridge of high
pressure at the surface will be in place. The continued westerly
flow will result in scattered light lake effect snow showers
across the western Adirondacks, but dry elsewhere. High
temperatures will be near normal in the 20s to lower 30s. Models
in good agreement with a fast-moving and compact short wave
trough moving through Thursday night. This will result in mainly
isolated to scattered snow showers from around I-90 northward,
with the greater coverage across the western/southern
Adirondacks. A quick half inch to one inch of snow is expected
in these areas.

More flat ridging across the region on Friday with mainly dry
conditions expected. Some light lake enhanced/upslope snow
showers could linger into the western Adirondacks, but most
areas will be dry. Tempertures will moderate slightly, with
generally upper 20s to mid 30s expected for highs. Tranquil
conditions in store for Friday night, with the Flat Ridge
remaining in place.

&&

Long term /Saturday through Tuesday/...
above normal temperatures expected with a low pressure system
passing to our west and north across the Great Lakes region and
eastern Canada early next week.

Guidance is in general agreement with the longwave pattern
featuring nearly zonal flow across the region over the weekend
with ridging being induced along the East Coast ahead of an
approaching closed low Monday. However, there are amplitude and
timing differences amongst the models. The European model (ecmwf) is deepen and
slower with the system however the weather prediction center
indicates there was better clustering with the GFS, gefs mean,
ec mean and CMC so this timing was favored for the forecast.
Based on this, the greatest chances for precipitation are Monday
night. Have the chances for precipitation increasing Sunday
night into Monday night. Precipitation types gets complicated
as night time lows are expected to be mainly in the 30s Monday
night. With uncertainty in both timing and temperature profile
have gone with rain and snow forecast however there could be
some freezing rain but that's very difficult to determine that
at this time. Quantitative precipitation forecast amounts are very uncertain also. With ice jams
in place across area will closely monitor expected temperatures
and potential rainfall. With the passage of this system back to
seasonable cold temperatures.

&&

Aviation /15z Wednesday through Sunday/...
coastal low located south of Long Island with pressure falls
occurring it its northeast. The low will continue to track
northeastward today and deepen. The steady snow will continue
this morning tapering off to snow showers and flurries as we
head into and through the afternoon. Snow lingering steady snow
possible across the capital district due to a brief period of
Mohawk-Hudson convergence.

IFR and lower conditions through much of the morning hours with
an improvement to MVFR expected by early afternoon and VFR by
late in the day/early evening. Conditions expected to improve a
bit quicker at kpou. Some cirrus clouds will stream across the
region tonight

Light to calm winds early this morning with northwest flow
developing and increasing to 6 to 10 knots during the day. Winds
shifting to the west in the evening.

Outlook...
thursday: no operational impact. No sig weather.
Thursday night: low operational impact. Slight chance of shsn.
Friday: no operational impact. No sig weather.
Friday night: no operational impact. No sig weather.
Saturday: no operational impact. No sig weather.
Saturday night: no operational impact. No sig weather.
Sunday: no operational impact. No sig weather.

&&

Hydrology...
ongoing flooding due to ice jams will continue to be addressed
with areal flood warnings. There could still be some lingering
issues as any existing ice jams may tend to become frozen in
place due to the continued cold temperatures over the next few
days. Warmer weather is not expected until the weekend.

In terms of precipitation, a moderate snowfall is ongoing for
much of the area into today, with heavy snowfall from the Mid
Hudson valley and Taconics eastward across western New England.
Mainly dry weather is expected through the weekend except for
some lake effect snow showers well north and west of the capital
district.

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...Winter Storm Warning until 3 PM EST this afternoon for ctz001-
013.
New York...Winter Weather Advisory until 3 PM EST this afternoon for
nyz032-033-038>043-047>053-058>060-063-082>084.
Winter Storm Warning until 3 PM EST this afternoon for nyz054-
061-064>066.
Massachusetts...Winter Storm Warning until 3 PM EST this afternoon for maz001-
025.
Vermont...Winter Storm Warning until 3 PM EST this afternoon for
vtz013>015.

&&

$$
Synopsis...jpv

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