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Area forecast discussion 
National Weather Service Albany New York
119 PM EDT Monday Oct 20 2014

Synopsis...
high pressure will slide offshore today. A complex weather
disturbance will organize in the Great Lakes today...and intensify
as it shifts to the middle Atlantic coast by Wednesday. Clouds will
increase today...with a long period of unsettled weather and
intermittent rain from tonight through Thursday night or Friday.

&&

Near term /until 6 PM this evening/...
as of 1245 PM EDT...still some breaks in the middle level clouds
translating northeast across the region...with more persistent
clouds across the southern Adirondacks. Middle level clouds should
gradually thicken and become more widespread from SW to NE during
the middle to late afternoon hours.

As for rain...thus far little if any has reached the surface despite
some weak radar returns across the southern Adirondacks...as low
level remain quite dry. As middle level isentropic lift
strengthens...it appears that some very light showers or sprinkles
should be able to reach the surface across this region by middle to late
afternoon. Other areas should remain generally dry through
sunset...other than some possible virga falling from the middle level
clouds.

Maximum temperatures are still expected to reach the middle 50s in valley
areas...and upper 40s/lower 50s across most higher
elevations...although portions of the southern Adirondacks will
likely remain even cooler...only middle 40s...due to more persistent
cloud cover and developing sprinkles/light showers.

&&

Short term /6 PM this evening through Wednesday/...
our region will still be under the influence of a cut-off low
pressure system...likely centered somewhere just south of Long
Island and southern New England through Wednesday night. Fairly good
agreement with models in terms of large-scale feature
placement...but there is still considerable spread regarding quantitative precipitation forecast
which is typical when dealing with cut-off lows. 00z gefs indicating
anomalously strong easterly flow of -3 to -4 stdev with our region
downstream of strongest anomalies. This signal is usually indicative
of heavy rainfall...although it is too early to pinpoint exact
amounts or locations that will receive the heaviest rainfall.

While Thursday will still be rather gloomy with the center of the
upper low only slowly meandering eastward towards Cape Cod and a
moist northeast flow persisting...the strongest wind anomalies
should start to lift north of the region...so rainfall amounts may
be less prolific by Thursday. Will continue to mention likely probability of precipitation.
While it will be cool and damp...temperatures aloft do not look cold
enough for snow even in the mountains for now.

The cut-off low should start to finally pull away and out to sea on
Friday...however we will still be influenced by a sprawling upper
level trough. As the flow turns more northwesterly...will confine
higher probability of precipitation to favored upslope areas north and west of the capital
district. Improving conditions are then expected during the weekend
along with a warming trend...as some sunshine is expected to finally
return after an expected overcast work week. Cannot rule out a few
upslope showers over the western Adirondacks on Saturday...but
otherwise dry weather is anticipated with high pressure building in
on Sunday.

&&

Long term /Wednesday night through Sunday/...
our region will still be under the influence of a cut-off low
pressure system...likely centered somewhere just south of Long
Island and southern New England through Wednesday night. Fairly good
agreement with models in terms of large-scale feature
placement...but there is still considerable spread regarding quantitative precipitation forecast
which is typical when dealing with cut-off lows. 00z gefs indicating
anomalously strong easterly flow of -3 to -4 stdev with our region
downstream of strongest anomalies. This signal is usually indicative
of heavy rainfall...although it is too early to pinpoint exact
amounts or locations that will receive the heaviest rainfall.

While Thursday will still be rather gloomy with the center of the
upper low only slowly meandering eastward towards Cape Cod and a
moist northeast flow persisting...the strongest wind anomalies
should start to lift north of the region...so rainfall amounts may
be less prolific by Thursday. Will continue to mention likely probability of precipitation.
While it will be cool and damp...temperatures aloft do not look cold
enough for snow even in the mountains for now.

The cut-off low should start to finally pull away and out to sea on
Friday...however we will still be influenced by a sprawling upper
level trough. As the flow turns more northwesterly...will confine
higher probability of precipitation to favored upslope areas north and west of the capital
district. Improving conditions are then expected during the weekend
along with a warming trend...as some sunshine is expected to finally
return after an expected overcast work week. Cannot rule out a few
upslope showers over the western Adirondacks on Saturday...but
otherwise dry weather is anticipated with high pressure building in
on Sunday.

&&

Aviation /17z Monday through Friday/...
VFR conditions expected to prevail through the 24 hour taf period
ending 18z Tuesday. High and middle level clouds already spreading
across the region ahead of an upper level trough approaching from
the Great Lakes. Ceiling heights are expected to remain fairly
steady through this evening...and should lower overnight but
remain in VFR range as the trough moves in. Scattered showers are
also expected to develop after 12z...so will mention vcsh at all
terminals. There are some indications of some showers affecting
all taf sites between 12z-18z but the coverage of showers looks to
be too limited to indicate a tempo or even a prob30...but later
taf issuances will better resolve how much coverage of showers
there will be Tuesday morning.

Winds will be southerly around 5-8 kts this afternoon..then
diminish to near calm tonight...then variable at 5kt or less
Tuesday morning.

Outlook...

Tuesday night to thursday: high operational impact. Likely rain.
Thursday night: moderate operational impact. Chance of rain.
Friday: moderate operational impact. Chance of rain showers.

&&

Fire weather...
today will be a dry day with a light wind becoming southerly around
10 miles per hour during the afternoon. Relative humidity values will drop to between 35 and
50 percent.

A vertically stacked upper level low pressure system will begin to
impact our weather tonight through at least Thursday night with
periods of rain...tapering to scattered showers by Friday. All areas
are expected to receive well over a quarter inch of rainfall during
this period.

Drier weather should return by the weekend.

&&

Hydrology...
no hydrologic issues expected into Tuesday. The weather is
expected to turn unsettled and wet by the middle of the week...as an
upper level low cuts off near the region. Intermittent rainfall is
expected from Tuesday into Friday.

In the periods of rainfall...some moderate to heavy bursts may
occur. The potential exists for one to three inches of rainfall
over portions of the Hydro service area depending on this systems
evolution...and track. This rainfall would occur over the period
of a few days...so no widespread flooding is anticipated at this
time.

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

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