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Area forecast discussion 
National Weather Service Albany New York
116 PM EDT Tuesday Sep 16 2014

Synopsis...
gradual clearing will occur as the day progresses as high pressure
begins to build in from the west. Generally fair and cool...fall
like conditions are expected for the remainder of the week as high
pressure dominates.

&&

Near term /through tonight/...
conditions will gradually improve as the afternoon progresses as
higher pressure at the surface begins to build in from the west.
Have pulled back a bit on highs for the day due to extensive cloud
cover/limited sunshine...looking at lower to middle 60s with 50s
across the higher terrain. There are some isolated light showers
being indicated on radar...these too will dissipate.

&&

Short term /Wednesday through Thursday night/...
tonight...very tricky call regarding the potential for low clouds
redeveloping across the region...as a persistent west/northwest flow
traverses the Great Lakes...underneath a strengthening subsidence
inversion...which could act to Trap Lake moisture in a somewhat
similar manner to sun nt/Monday am. For now...have indicated at least
partly cloudy skies across the region...but there certainly is the
potential for skies to become mostly cloudy/overcast at times.
Have sided with the warmer met MOS for min temperatures...assuming that
at least some patches of clouds pass through. In addition...even
if more breaks develop than are currently expected...then a fairly
moist boundary layer will likely allow areas of fog to form.
So...forecast mins generally range from the upper 30s to middle
40s...warmest in valley areas. Based on these temperatures...no frost
statements have been issued.

Wednesday-Wednesday nt...after any low clouds/fog burn off/lift...expect
mostly sunny skies for much of Wednesday...with temperatures reaching 65-70 in
valleys...and lower 60s across higher terrain. For Wednesday nt...some
high and middle level clouds will likely begin to stream southeast across
the region in advance of a cold front across southeast Canada. Some
showers could reach portions of the southern Adirondacks by
daybreak Thursday with the front. Have generally sided on the
warmer side of guidance for min temperatures...with mainly 40s
expected...although some upper 30s will be possible across
portions of the southern Adirondacks and the Lake George region.

Thursday-Thursday nt...a cold front will settle southward across the region
during Thursday. This front will have limited moisture
availability...so it appears that the front will mainly be
accompanied by a wind shift...and some middle level clouds. Behind
the front...it is possible that some low clouds may develop
briefly. So...in general...a mix of sun and clouds can be expected
on Thursday...with possibly a period of mostly cloudy skies during the
midday hours. Again...no probability of precipitation have been indicated...although can
not completely rule out a sprinkle or two across some higher
elevations. Much colder air will seep southward in the wake of the
front...especially for Thursday nt. This may set the stage for a fairly
widespread frost/freeze situation...although there is the
possibility that the wind may persist just long enough in the
valley areas to limit overall frost potential. However...across
higher elevations such as the western Adirondacks...eastern
Catskills...and possibly southern Vermont...temperatures could dip to near or
slightly below freezing...even with some wind. So...these areas
will be most likely to experience a freeze. Will highlight this
potential in the hwoaly. Maximum temperatures on Thursday should still reach the
Lower/Middle 60s in valley areas from Albany north and west...and
65-70 to the south ahead of the front...with mainly 50s to lower
60s for higher terrain. Min temperatures for Thursday nt/Friday am are expected
to fall to around freezing across the aforementioned higher
elevations...with mainly 30s to lower 40s elsewhere.

&&

Long term /Friday through Monday/...
dry weather is forecast during the first half of the long term forecast
period with an increasing chance of showers during the second half
of the long term period.

On Friday expect a large ridge of high pressure to be over the
northeast with the center of the high sliding off the eastern
Seaboard on Saturday as a warm front lifts northeast into the
eastern Great Lakes. Dry weather is expected Friday through Saturday
with a moderating trend in temperatures as a return flow develops on
Saturday with high pressure off the East Coast. Highs on Friday are
expected to be in the upper 50s to middle 60s with lows Friday night in
the upper 30s to middle 40s and highs on Saturday in the middle 60s to
lower 70s.

Saturday night and Sunday...expect much of forecast area to remain dry as flow
ahead of next frontal system moving into the eastern Great Lakes
becomes increasingly more parallel to the frontal boundary...thus
delaying eastern progression of the precipitation. Any showers during this
period will be mainly confined to the northwest third of the forecast area.
Expect lows Saturday night to be in the upper 40s to middle 50s with
highs on Sunday very mild in the upper 60s to around 80.

Sunday night and Monday...the cold front is expected to move through
the forecast area by Monday morning with a trough of low pressure in the
eastern Great Lakes region. For now have forecast widely scattered
to scattered showers both Sunday night and Monday with the highest
probability of precipitation across the northern portion of the forecast area which will be closer to the better
dynamics. Expect lows Sunday night in the upper 40s to upper 50s
with highs on Monday in the upper 50s to middle 70s.

&&

Aviation /17z Tuesday through Saturday/...
lingering MVFR ceilings will give way to VFR flying conditions this
afternoon and evening...before IFR/MVFR fog develops at the taf
sites tonight.

This afternoon...have placed tempo groups at the taf sites for
intermittent periods of MVFR ceilings between 18z-20z. Afternoon
mixing will give way to VFR flying conditions by 20z with gradually
clearing skies through the evening hours. Winds will be out of the
northwest around 5-10 knots.

Tonight into Wednesday...with high pressure building across the
region...skies are expected to become clear with calm winds.
Lingering moisture in the low-levels will result in IFR/MVFR fog at
the taf sites tonight amidst the ideal radiational cooling
conditions. Expect IFR fog to develop first at kgfl and kpsf in the
03-06z timeframe...and persisting through the remainder of the
overnight period. Have gone with MVFR fog at kalb and kpou as
slightly better mixing should limit IFR fog formation...although
will need to keep an eye on trends tonight.

VFR flying conditions will return for the remainder of the taf
period after 12z Wednesday with few-scattered cumulus around 5 kft as high
pressure continues to build across the region. Winds tonight will
trend towards calm with light and variable winds expected Wednesday
less than 5 knots.

Outlook...
Tuesday night-Sat: no operational impact. Patchy fog possible late at
night early in the am.

&&

Fire weather...
showers will gradually taper off today as an upper level
disturbance...and associated weak surface trough move east. Gradual
clearing is expected for later today and tonight...as high pressure
builds in from the west. Generally fair and cool conditions are
expected for the remainder of the week as a cold front with limited
moisture settles southward on Thursday.

The relative humidity will fall to 50-60 percent this afternoon...then recover to
90-100 percent tonight with dew formation expected. The relative humidity will
fall to 40-55 percent for Wednesday afternoon.

Light/variable winds will become west to northwest this afternoon
at 10-20 miles per hour...then decrease to 5-15 miles per hour tonight. Winds will back
into the west to southwest Wednesday...at 5-10 miles per hour.

&&

Hydrology...
no widespread Hydro problems are expected through at least Saturday.

Light to moderate rainfall will taper off across the region
today...with total rainfall amts of one quarter to one half inch
expected for areas north of the Mohawk River...and generally one
tenth to one quarter of an inch further south and east...with the
lowest amts generally across the middle Hudson Valley and northwest CT.
These rainfall amts will have negligible effects on area
rivers/streams.

Dry conditions are then expected for tonight through at least
Saturday.

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...iaa/snd/kl
near term...iaa/snd
short term...snd/kl
long term...11
aviation...irl
fire weather...iaa/kl
hydrology...iaa/kl

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