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fxus61 kaly 231746 
afdaly

Area forecast discussion
National Weather Service Albany New York
1246 PM EST Tue Jan 23 2018

Synopsis...
a warm front will move through the region this morning with
above normal temperatures. A low pressure system and its cold
front will bring periods of rain to eastern New York and western
New England late this morning into the afternoon. In the wake
of the cold front tonight, colder more seasonable air will
return with brisk conditions for the mid week. Some light snow
accumulations will be possible north and west of the capital
region Tuesday night into Wednesday morning.

&&

Near term /until 6 PM this evening/...

..Flood Watch remains in effect through Wednesday morning for
all eastern New York/western New England outside of north.
Herkimer/Hamilton cos...

As of 1245 PM EST, steady rain beginning to taper to showers
from southwest to northeast. There remains a band of moderate-
locally heavy rain, extending from southwest Vermont south through
western Massachusetts and into the Mid Hudson valley, which is moving east.
This heavier band should move across northwest CT, Berkshire Colorado and the
remainder of southern Vermont over the next 1-2 hours.

Temperatures have finally risen above the freezing mark across
the previous advisory area of Warren/N. Washington cos and
Windham Colorado Vermont. However, there will likely remain some pockets of
icing on untreated ground surfaces for at least a few more hours
due to the freezing rain/ice accretion from this morning.

Also, some reports of ice accretion in trees in Windham co, at
least enough for some small branches to sag.

For the remainder of this afternoon, as a mid level dry slot
moves northeast, expect showers to decrease for a period through
mid afternoon. In fact, some breaks of sun will be possible
within portions of the Mid Hudson valley and Litchfield Colorado CT.

Later this afternoon, as the leading edge of the upper level
cold pool/shortwave approaches from the west, some low topped
convection may develop, with rain showers in lower elevations,
and rain changing to snow showers across higher elevations.
There could be a few embedded convective elements with isolated
lightning strikes, graupel, and gusty winds as well.

Temperatures should finally rise into the mid 40s to lower 50s
in most areas by mid/late afternoon, although may take a while
longer in protected valley areas of southeast Vermont and the upper Hudson
Valley.

&&

Short term /6 PM this evening through Thursday night/...
the Flood Watch will continue into the night time period for ice
jams or a combo of ice jams, snow melt, and runoff. However, we
will not have 2 consecutive days of an avg temp of 42f or
greater for more widespread break up ice jam potential issues
like what occurred on 12-13 Jan. Total rainfall will be in the
half an inch to one and a half inch range.

Tonight...much colder air will rush back into the forecast area
as a secondary cold front moves across the region. The rain
showers will transition to snow showers. West to northwest
orographic enhancement off the western spine of the Adirondacks
and southern greens may yield 1-3 inches of snowfall with some
locally higher amounts. Some lake moisture will be tapped for
the snow showers to spread into the Mohawk Valley/northern
Catskills and perhaps even the capital region for some coatings
to a half an inch or so. The cold air advection will allow temps
to fall back into the 20s with some teens over the southern
dacks. The winds will increase from the west to northwest at
10-20+ mph with some gusts in the 30-45 mph range especially
funneling down the capital region/Mohawk Valley into the western
New England higher terrain and northern Catskills especially
after midnight.

Wednesday will feature brisk and cold conditions with snow
showers and flurries ending especially north and west of the
capital region with few light snow accums. The latest BUFKIT
momentum Transfer profiles indicate some 30-35 kt gusts are
possible if we mix to 2-3 kft above ground level. The winds will diminish in
the afternoon as the cyclone accelerates northeast into the
Canadian Maritimes. High temps may be achieved prior to
noontime, and may steady or slight fall thereafter with highs in
the 20s to lower 30s with a few mid 30s from aly south down the
Hudson River valley.

Wednesday night...the mid and upper trough axis moves across the
region with flurries/isolated snow showers west of the Hudson
River valley ending. It will be cold with lows in the single
digits to teens with some below zero readings over the
Adirondacks park.

Thu-Thu night will feature below normal temps with Arctic high
building in from southeast Ontario and Great Lakes region. Temps
will run about 5 degrees below normal for late Jan with still
northwest winds of 10 to 20 mph due to the chilly cyclonic flow
on the back side of the trough.

&&

Long term /Friday through Monday/...
the period starts out Friday with a strong near-1040 mb area of high
pressure over the region, gradually shifting eastward to the
southern New England coast late in the day. This will result in dry
conditions and near normal temperatures. Dry conditions will prevail
Friday night into Saturday, as upper level heights rise across the
region, while the surface high slowly moves eastward into the western
Atlantic. A return southwest flow will set up around the periphery
of the departing anticyclone, which will allow for a moderating
trend. Temps forecast to be around 10-15 degrees above normal on
Saturday.

Models then start to diverge late Saturday through early next week,
as the European model (ecmwf) and CMC indicate an amplifying pattern with strong
upper level ridging along the East Coast persisting through the
weekend, while the GFS is much less amplified and has a northern
stream cold front pushing through. Will side with the more amplified
pattern for now, which has shown more consistency among the European model (ecmwf)
and CMC the past few runs.

The resulting forecast is increasing chances for rain Saturday night
into Sunday, as a frontal boundary sets up across our area with a
mild southerly flow aloft, while a deepening upper level trough
pushes east from the Midwest into the Ohio Valley region. A wave of
low pressure is then forecast to develop along the front and track
northeastward right through eastern New York and western New England
Sunday night into Monday. This would result in possible prolonged
and potentially heavy rainfall event, with rain changing to snow on
the back side west of the Hudson Valley. This is still 6-7 days
away, but we will continue to monitor the evolution of this system
as it could cause hydrologic issues associated with heavy rainfall
and/or wintry precip on the back side of cyclone into early next
week.

&&

Aviation /18z Tuesday through Sunday/...
frontal system continues to impact the region, although the
steadiest rainfall is starting to move off to the northeast. Through
the remainder of the afternoon hours, there will continue to be some
lingering showers as the low pressure area crosses the region. With
our area still on the cool side of the storm system, plenty of
lingering low level moisture and light surface winds will keep lots
of low clouds and areas of fog around, with IFR/LIFR conditions in
place. Visibility will be as low as 1/2sm (mainly for kgfl) with
cigs less than 1000 feet for much of the area. Kpou may be the first
site to see some improvement by late this afternoon.

By this evening, the cold/occluded front will be moving
through the area, and westerly winds will allow for some mixing.
This should start to allow for flying conditions to improve for all
sites , initially to MVFR and gradually back to VFR during the
overnight hours tonight, as some drier air starts to work in from
the west. Any showers should be ending with the passage of the
front.

Although winds will be light this afternoon, they will increase from
the SW around 5 kts this evening and eventually become westerly
around 10 kts by overnight. Some higher gusts are possible later
tonight, especially at kalb/kpsf, with some gusts up to 25 kts
possible.

During the day Wednesday, mainly VFR conditions are expected with
bkn cigs around 3500 feet. West-northwest winds will be 10-15 kts with some
higher gusts from time to time.

Outlook...

Wednesday night to saturday: no operational impact. No sig weather.

&&

Hydrology...
ongoing flooding due to ice jams will continue to be addressed
with areal flood warnings in Warren County, as some lingering
issues continue due to existing ice jams which froze in place.

Temperatures will continue to run above normal into today. The
mildest night and day will be today with highs mainly in the
40s to lower 50s with a much colder and more seasonable airmass
returning tonight and through the remainder of the week.

A low pressure system and its cold front will bring a moderate
to locally heavy rainfall to the area today. Quantitative precipitation forecast amounts are
forecast at this time to range from half an inch to an inch and
a half. The highest amounts are expected north and east of
Albany and the capital region, extending into the Mid Hudson
valley and northwest CT.

The rain is expected to cause rises on rivers and streams, which
may move and dislodge ice and may cause flooding near ice jams.
Mostly within bank rises are expected based on the latest nerfc
forecasts and the mmefs. However, the Rising River/stream
levels from runoff could be enough to dislodge ice jams which
have been frozen in place over the past 10 days. Therefore, a
Flood Watch has been issued, mainly to heighten awareness that
ice jams frozen in place could dislodge and/or cause new
flooding in some areas. Poor drainage flooding and ponding of
water is also likely due to melting snow and enhanced rainfall
rates.

Colder and drier weather is expected from the mid week into
early Saturday. However, another slow moving front may bring
more rainfall late in the weekend.

Our latest winter/Spring flood potential outlook (esfaly) was
issued this past Friday.

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...Flood Watch through Wednesday morning for ctz001-013.
New York...Flood Watch through Wednesday morning for nyz038>043-047>054-
058>061-063>066-082>084.
Massachusetts...Flood Watch through Wednesday morning for maz001-025.
Vermont...Flood Watch through Wednesday morning for vtz013>015.

&&

$$
Synopsis...wasula
near term...kl/wasula

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