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Area forecast discussion 
National Weather Service Albany New York
106 am EST Sat Dec 27 2014

Synopsis...
high pressure over the southeast states will move off the
coast tonight into Saturday...as a cold front approaches from the
Great Lakes region for Saturday night and Sunday. This front will
bring some clouds for late Saturday into Sunday...along with some
rain showers for valleys...and rain or snow showers for higher
elevations. Fair weather...and more seasonable temperatures should
return by early next week.

&&

Near term /until 6 am this morning/...
mainly mostly clear skies across area with some cirrus streaming
overhead. The exception is across the far northern portion of the
forecast area where have mostly cloudy conditions. Cloud cover is
expected to gradually spread/shift southward. Temperatures are
close to their overnight minimums...then they should hold nearly
steady or begin to rise by daybreak. Overall minor adjustments have
been made.

&&

Short term /6 am this morning through Monday night/...
Saturday...low clouds should initially remain mainly north of
Interstate 90 in the morning...with partly to mostly sunny skies
expected for areas mainly S and east of Albany. However...low level
warm advection may allow for the low clouds to expand further S
and east in the afternoon. So...the best chance for sunshine will be
in the morning hours...and mainly S and east of Albany...with clouds
more prevalent to the north and west of Albany. Right in the capital
region...it appears that some breaks of sun could occur in the
morning...before clouds become more dominant in the afternoon.
Despite the increasing clouds...little in the way of precipitation is
expected through around sunset...when some rain showers
may eventually develop/reach the western Adirondacks. Maximum temperatures
are expected to reach the middle 40s to around 50 from Albany and
points S and east...and mainly upper 30s to middle 40s to the north and west.

Sat nt-sun...a cold front will approach from the Great Lakes
region...and pass southeast across the forecast area Sunday morning. Some
light showers are expected to immediately precede and accompany
the frontal passage...with the best chance across the western
Adirondacks...and west facing upslope areas of southern Vermont and
western Massachusetts. Some snow may mix in across the western Adirondacks
toward and just after daybreak Sunday as colder air follows in the
wake of the front. Rain showers should shift south and east Sunday
morning...becoming confined to the southeast Catskills...middle Hudson
Valley...southern Berkshires and northwest CT by Sunday afternoon. Some
wet snow could occur across higher elevations of the southeast Catskills
and western Berkshires before showers end late Sunday. As for
temperatures...Sat nt should be rather mild due to increasing
clouds...low level warm advection...and also a developing
south/southwest wind. The mildest temperatures are expected within the
immediate Hudson River valley...where temperatures may remain above 40
through much of the night. Elsewhere...expect min temperatures to fall
into the Lower/Middle 30s...mainly due to wet bulb effects once rain
showers occur. Most min temperatures should remain above the freezing
mark. For Sunday...expect maximum temperatures in valleys to reach the
Lower/Middle 40s...and possibly 45-50 across the middle Hudson Valley.
Higher elevations will remain cooler...generally in the upper 30s
to lower 40s...with temperatures across higher elevations of the southern
Adirondacks and southern Vermont possibly falling in the afternoon
through the 30s.

Sunday night...there remains some possibility of a weak wave
developing along the southward moving cold front across the Middle
Atlantic States late sun nt into early Monday. This may allow some
light precipitation to expand back into portions of the middle Hudson Valley
and northwest CT sun nt. This is a very low probability...with most
current guidance suggesting any precipitation remain south of our region.
Have indicated some slight chance probability of precipitation across extreme southern areas
to account for this small possibility of precipitation...but again...at
this time...most sources of guidance suggest it remains to the
south. Temperatures for sun nt should fall into the 20s across most
areas...with some teens possible across portions of the southern
Adirondacks. Persistent high and middle level clouds may limit how
cold it gets despite cold advection...so have generally sided
closer to...or a bit above the slightly milder mav MOS.

&&

Long term /Tuesday through Friday/...
after a long period of above normal temperatures...the long term period
will feature a return to normally cold temperatures and mainly dry weather
/exception to this will downwind of Lake Ontario with a return of
lake effect snow/.

Global models continue to trend toward a couple of shots with Arctic
air for the last few days of 2014. The first piece of this colder
air arrives Monday as a large high pressure...near 1050mb building
into Montana...extends its influence eastward across the Great Lakes
region and New England. H850 temperatures are prognosticated to drop back to
between -10c to -15c Monday into Tuesday. This will equal too
surface temperatures near seasonable normals.

The next shot of colder air arrives Wednesday as the h850 temperatures
drops back a few more degrees. This along with a near parallel flow
through the low-middle troposphere will favor lake effect snow
redeveloping downwind of Lake Ontario. We will keep probability of precipitation into
portions of the dacks through the middle week period with lake effect
snow showers. The remainder of the region will be mainly dry and
colder.

Overall...temperatures near normal and precipitation below normal
expected during this long term period of the forecast.

&&

Aviation /06z Saturday through Wednesday/...
high pressure will shift eastward with the center of the surface high
shifting offshore the southeast coast this evening as a low
pressure system approaches. The surface low will well modeled to
to move across the Great Lakes region into eastern Canada today a
and tonight while dragging its associated cold front into the
region tonight. The upper ridge will hold fairly steady however
the flow will become southwesterly with time.

Overall looking at VFR conditions through 06z/Sunday. The
exception will be for the possibility for some MVFR at kgfl early
this morning. Otherwise clouds will be on the increase especially
this afternoon and evening.

Surface winds will light...mainly calm overnight with a south-southwest
flow developing today with a more westerly flow at kpsf.

Outlook...
Sun night-Wed: no operational impact. No sig weather.

&&

Hydrology...
most river levels are now receding across the region.

A cold front is expected to bring some showers of mainly
rain for valleys...rain/snow across higher elevations...for Sat nt
into early Sunday. At this time...it appears that liquid equivalent
amts should remain under one quarter of an inch...therefore having
negligible effects on receding river levels.

Generally dry conditions...and colder temperatures...are expected
into at least early next week.

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...kl
near term...iaa/kl/gjm
short term...kl
long term...bgm
aviation...iaa
hydrology...kl/Snyder

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