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Area forecast discussion 
National Weather Service Albany New York
447 PM EST Thursday Mar 5 2015

Synopsis...
high pressure will build eastward from the central U.S. Tonight
into Friday...as Arctic air filters back into our region. The
Arctic air mass will remain in place through Friday. A couple of
weak...fast moving clippers may bring some snow showers or
flurries to portions of the region over the weekend...despite a
slight moderation in temperatures.

&&

Near term /until 6 am Friday morning/...
as of 445 PM EST...the precipitation associated with the frontal
wave remains just S and east of the region...despite a thick middle
level cloud canopy which extends well north and west across most of the
region. Temperatures are generally in the Lower/Middle 20s within the Hudson
River valley...with mainly teens across much of the Mohawk Valley
and higher elevations across western New England...with some
single digits and lower teens across higher peaks across the
Adirondacks.

Winds remain a bit brisk...from the northwest to north at 10-15 miles per hour with some
stronger gusts in channeled valley areas.

For the most part...the clouds should gradually thin from northwest to southeast
through midnight...with mainly clear skies expected after
midnight. The one exception could be some patchy lower clouds
across portions of the western Adirondacks/Mohawk Valley and
eastern Catskills...where some added low level lake moisture may
contribute.

The biggest question overnight will be how quickly the winds will
decrease. We still expect brisk conditions well into this
evening...with some wind gusts possibly gusting into the 15-20 miles per hour
range across portions of the Mohawk Valley region and Berkshires.
Then...winds should decrease more rapidly after midnight. Should
this occur...the combination of light winds...mainly clear skies
and a snowpack in place could allow temperatures to drop rapidly after
midnight...especially right before daybreak. Have therefore sided with
the colder guidance...with widespread min temperatures of 5 above to 5
below zero in most lower elevations...except for some -5 to -10
mins across the Lake George/Saratoga regions. Elsewhere...slightly
colder mins of -10 to -15 across the southern adirodnacks.
Again...such low min temperatures depend on if the winds drop off after
midnight. Should winds persist a bit longer...warmer min temperatures
would result. Also...given the fact that the lowest temperatures are
forecast to occur with very light to calm winds...no wind chill
headlines are indicated.

&&

Short term /6 am Friday morning through Sunday/...
Friday...high pressure will build across from the west.
However...a potent upper level shortwave...currently visible on
afternoon water vapor imagery across the north/Central
Plains...will pass just south of the region later in the day.
Deep...dry air beneath this feature will limit any thicker clouds
and precipitation from occurring...but there should be at least some
patches of high/middle level clouds increasing in the afternoon.
So...the day should start mostly sunny/sunny...before increasing
high and some middle level clouds develop during the middle to late
afternoon. Friday maximum temperatures should reach the Lower/Middle 20s in
valleys...and 15-20 across higher elevations.

Friday night...yet another tricky call on potential min temperatures.
Areas of high and middle level clouds associated with the
aforementioned upper level shortwave will continue through around
midnight before rapidly thinning. However...lower clouds
associated with a surge of low level warm advection and some added
lake moisture will impinge on the region from the west and
northwest toward daybreak Saturday. How much time elapses between
these two cloud areas will determine just how low temperatures can
get...as the potential for very cold min temperatures will exist given
light winds for a portion of the night. For now...have utilized a
blend of the mav/met MOS...with most mins in the 5 to 10 above
range...except for some mins around or just under zero across
portions of the southern Adirondacks and Lake George region. Some
snow showers or flurries could also develop toward sunrise Sat in
association with the approaching low level jet maximum and clouds.

Sat-sun...a series of weak clipper type systems will pass just
north of the region...one late Sat...and another on Sunday. Each
system will have weak surges of middle level isentropic lift...and
should allow for some snow showers across the southern Adirondacks
and upper Hudson Valley into southern Vermont...where chance to likely
probability of precipitation are indicated. Have only indicated slight chance probability of precipitation for most
areas south of Interstate 90...which will be further removed from
the dynamics associated with each system. Some light snowfall
accums will be possible both Sat and sun...mainly a couple of
inches across the western Adirondacks for the weekend total...and
generally a dusting to an inch further S and east. Despite the
possibility of some clouds and snow showers...temperatures will gradually
moderate overall this weekend...with Sat maximum temperatures reaching the
lower 30s in valley areas...with mainly 20s across higher
elevations. Sat nt/sun am mins should only fall into the 20s for
most areas. Then...sun maximum temperatures are expected to reach the middle to
upper 30s in valleys and upper 20s to lower 30s across higher
terrain. However...even warmer maxes could occur in portions of
the middle Hudson Valley and lower elevations across Litchfield
Colorado...where some downsloping from a southwest low level wind...and
the possibility of more breaks of sunshine could help boost temperatures
upward.

&&

Long term /Sunday night through Thursday/...
mainly dry weather and temperatures moderating to seasonably warm
readings expected during the long term period. The only chance for
precipitation during this period will be Sunday night and Monday as a weak
low pressure system tracks east across central Canada...and drags a
weak cold front through the region. Only probability of precipitation of 20 to 40 percent
have been forecast for this event.

Although it will seem very mild compared to recent conditions...
forecast highs in the upper 30s and 40s for much of next week will
be close to normal.

Specifically...lows Sunday night will be in the middle teens to middle
20s. Highs Monday 30 to 40. Lows Monday night middle teens to middle 20s.
Highs Tuesday in the upper 30s to lower 40s. Lows Tuesday night in
the 20s. Highs Wednesday in the 40s. Lows Wednesday night in the
20s. Highs Thursday in the upper 30s and 40s.

Wednesday of next week will be the warmest day...with the first
chance in a long time that temperatures may reach 50 degrees. The last time
the high temperature was at least 50 degrees at Albany New York was back
on December 27th...at Poughkeepsie New York and Bennington Vermont it was back
on January 4th...and at Glens Falls New York and Pittsfield Massachusetts it was on
December 25th.

&&

Aviation /21z Thursday through Tuesday/...
a wave of low pressure continues to move along a frontal boundary
draped across the Middle Atlantic States. It will head off the coast
and out to sea this afternoon. The precipitation shield associated
with the low is just south of kpou and should remain south of kpou
but will keep vcsh for this afternoon there. A secondary cold
front has also moved across the area which shifted the winds more
northerly and has opened the door to a colder and drier airmass to
filter in. Higher pressure will build in from the west this
afternoon and tonight continuing through tomorrow.

VFR conditions are expected at all sites through the taf
period...18z/Friday.

Northwest to north winds generally 10 to 15 knots with gusts to up
to around 25 knots will decrease Slater this afternoon...then winds
diminish tonight to near calm. North to northwest winds at 6 knots or
less are expected tomorrow morning.

Outlook...
Friday-Friday night: no operational impact. No sig weather.
Sat-Mon: low operational impact. Slight chance shsn.
Monday night-Tue: no operational impact. No sig weather.

&&

Hydrology...
no widespread Hydro problems are expected through the next 5 days.

Arctic air mass will dominate through Friday...with temperatures
remaining well below freezing. The Arctic air will retreat over
the weekend...but temperatures should still average below normal.

A moderating trend is then expected early next week with near normal
temperatures and above freezing daytime temperatures. Some snow will start
to melt...but will be on a diurnal cycle with temperatures falling back
below freezing at night.

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/jpv
near term...kl
short term...kl
long term...iaa/gjm
aviation...NAS
hydrology...kl/jpv

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