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fxus61 kaly 111144 
afdaly

Area forecast discussion
National Weather Service Albany New York
644 am EST Wed Dec 11 2019

Synopsis...
light snow across southeastern areas will end this morning and
clouds will break for some sun. As much colder air moves back
into the region, some lake effect snow will develop for northern
and western parts of the area for late today through tonight.
Cold temperatures will continue for Thursday, but milder
temperatures and more rain is expected for Friday into the
weekend.

&&

Near term /until 6 PM this evening/...
as of 644 am EST...snow associated with an anafront is finally
ending across the Mid Hudson valley, southern Berkshires and northwest
CT. One last band of now is now moving across Dutchess, southern
Berkshire and Litchfield counties. Up to four inches of snow
has already accumulated across the region, with the highest
totals across the higher terrain. This final band will shift
eastward and a few lingering snow showers may continue across
Litchfield County over the next few hours, but the bulk of the
accumulation is now done. Winter Weather Advisory continues
through 10 am for Litchfield, as snow covered roadways is making
for a slow morning commute across northwest CT.

Elsewhere, it will be a cloudy start to the day, but breaks in
the clouds are expected at some point during the day. It may
take until afternoon for all the higher clouds to finally clear
out. Despite any clearing, it will be noticeably cooler today,
as temperatures will only be reaching the mid 20s to mid 30s for
highs today.

&&

Short term /6 PM this evening through Friday night/...
a secondary boundary (an Arctic cold front) will be moving
across the area for this evening. Some snow showers are expected
across the western Adirondacks after 6 PM as a combination of
some lake moisture, upslope flow and the passing boundary all
contribute to a broken line of snow showers. Some of these may
see some locally heavier bursts, as 00z href suggest rates
may briefly exceed 1 inch per hour across northern Herkimer and
northwestern Hamilton counties for this evening with some
localized squalls across the western Adirondacks possible.
Otherwise, winds will switch to the northwest behind the front
and become gusty for this evening into tonight.

For later tonight (around and just after midnight), a broken
band of lake effect snow looks to develop across the Mohawk
Valley as much colder air surges into the region aloft. Inland
extent may not be quite as far as what models suggested
yesterday, but a coating to an inch of snowfall is possible for
areas west of Amsterdam for tonight. Still can't rule out a few
flurries reaching the capital region, but best chance for
accumulation looks to be to the west. This band looks to recede
closer to the Lakeshore and lift northward towards daybreak
Thursday. Lows tonight will be in the teens.

On Thursday, any lake effect will end across our area thanks to
an approaching area of high pressure. As a result, skies will be
fairly clear, but temps will be rather chilly, with highs only
in the 20s. Some clouds may return for Thursday night, but it
still looks fairly chilly in teens and 20s, but it will continue
to be dry.

Clouds will increase even more for Friday morning, as the next
system approaches. This will be a low pressure area lifting
northward out of the southeast and will have plenty of Atlantic
moisture associated with it. Models still don't agree on the
exact track, but both temps aloft and within the boundary layer
will be warming quickly. Precip should be beginning sometime
between Friday afternoon and Friday evening, with fairly steady
precip expected for Friday night. There could be a little
wintry mix at the onset across the higher terrain (lingering
longest across the sheltered valleys of the Adirondacks and
within southern vermont), but most of the precip will be in the
form of rain as temps warming through the 30s on Friday and
hold steady or slowly rise for Friday night.

&&

Long term /Saturday through Tuesday/...
long term looks to be a period of active weather.

For Saturday into Sunday a negatively tilted longwave trough at
500mb moves from the Tennessee Valley northeast across New England.
During this time, surface low pressure over the southeast U.S. Is
forecast to consolidate over New York state and move into eastern
Canada. Precipitation looks to be mainly rain, although there could
be a period of freezing rain Saturday morning across the southern
Adirondacks and southern Vermont, and it may end as some snow
showers across the higher terrain on Sunday. Rainfall and
snowmelt will likely lead to near bankfull rises on area rivers
again. High temperatures on Saturday in the 30s and 40s. Low
temperatures Saturday night from the upper 20s to upper 30s. Highs
on Sunday in the 30s and 40s.

Behind the low pressure system, a brief shot of Arctic air will move
across the area on Sunday night and Monday. There will be some
scattered snow showers downwind of Lake Ontario over the southern
Adirondacks and western Mohawk Valley. Lows Sunday night mid teens
north to mid 20s south. Highs on Monday from the mid 20s north to
mid 30s south.

Another storm system is forecast to impact the region on Tuesday.
Trends have been to bring system farther northward with time so
precipitation type is in question. A mixed bag is likely. Lows
Tuesday mid teens north to mid 20s south. Highs Tuesday from the
upper 20s north to upper 30s south.

&&

Aviation /12z Wednesday through Sunday/...
some light snow showers or flurries still possible at kpou this
morning, but heaviest snow is now southeast of Albany taf
sites. MVFR conditions due to snow and ceilings still possible
at kpou through 14z. Some light snow showers with MVFR
ceilings/visibility possible kalb between 12/05z and 12/10z.
Mainly VFR conditions through rest of taf period elsewhere.

Winds will be westerly at 10-15 kt. Some occasional gusts to 25
kt are possible at kalb and kpsf.

Outlook...

Thursday night: no operational impact. No sig weather.
Friday: moderate operational impact. Chance of rain.
Friday night: high operational impact. Definite rain.
Saturday: high operational impact. Definite rain.
Saturday night: moderate operational impact. Likely rain showers...ra.
Sunday: moderate operational impact. Breezy chance of rain showers.
Sunday night: low operational impact. Breezy slight chance of shsn.
Monday: no operational impact. No sig weather.

&&

Hydrology...
as temperatures cool off for today and tonight, runoff from the
recent rainfall and snow melt should slow down. Any additional
precipitation in the form of snow early this morning for
southern areas won't have any immediate impact on rivers and
streams.

For the remainder of the work week, rivers and streams
will slowly recede, although some rivers (such as the Housatonic
river) may remain elevated. Another storm may bring more
moderate to significant rain to the region for Friday into
Saturday, which will cause rivers and streams to rise once
again. Many rivers may approach bankfull levels and some
flooding will be possible, especially across western New
England.

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 until 10 am EST this morning for
ctz001-013.
New York...none.
Massachusetts...none.
Vermont...none.

&&

$$
Synopsis...frugis
near term...frugis

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