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Area forecast discussion 
National Weather Service Albany New York
1108 am EDT Wednesday Sep 17 2014

Synopsis...
high pressure will weaken and slide south and east of the region
today. This will allow for a cold front...currently just north of
the Great Lakes region...to track across the region on Thursday.
Limited moisture associated with this cold front so most of the
day should remain dry. Then a much cooler air mass filters into
the region Thursday night as strong high pressure settles across
the northeast corridor through the end of this week. Temperatures
are expected to rebound to above normal by this weekend ahead of
an approaching low pressure system.

&&

Near term /until 6 PM this evening/...
mainly sunny skies today in valley locations and partly sunny across
the mountains. As the surface high weakens and slides south and east
of the area today...the cyclonic flow aloft attempts to sharpen a
bit upstream and will slowly move a cold front over southern Canada
closer to our region. Due to the cyclonic flow aloft...diurnally
driven cumulus/SC should occur over the region.

Highs today will be in the 60s and lower 70s.

&&

Short term /6 PM this evening through Friday/...
much cooler temperatures expected Thursday night into early Friday
morning.

Tonight...as the surface ridge becomes further removed from the
region...the upstream cold front will further its forward progress
into the St Lawrence Valley. Meanwhile the main upper
support...seen in the water vapor imagery just east of Lake
Winnipeg...is expected to remain north and west of the region.
This would suggest the best upper support will have minimal impact
to the region and too far removed for direct impacts. So we will
increase cloud cover slowly from north to south overnight and keep
slight chance probability of precipitation across the dacks overnight. Low temperatures
are expected to remain into the 40s.

Thursday...cold front will move across the region with mainly
cloud cover. But can not rule out a shower or two across the
region as cross sections suggest low level Omega supports lift at
or below h700 where relative humidity values are over 90 percent. This lift
rapidly dissipates south and east of Albany so we will keep the
weather dry for now for those areas. Otherwise...just slight
chance probability of precipitation for light rain showers.

Thursday night...1025mb surface high will build into the region
clearing out the skies as mean relative humidity values drop back or below 30
percent along with diminishing winds. H850 temperatures are prognosticated to
fall back to around 0c across the dacks and Lake George region
with around +5c for the southeast Catskills...middle Hudson Valley
and northwest CT. This will set the stage for frost conditions across
mainly the terrain and north of Albany with freeze conditions for
the dacks and northern Warren County. We will continue to
highlight in the severe weather potential statement.

Friday...big bubble no trouble as surface high /1028mb/ slides
across the northeast corridor. Wall-to-wall sunshine is forecast
with a rebound in temperatures into the 50s across the terrain and
low-middle 60s elsewhere.

&&

Long term /Friday night through Tuesday/...
forecast confidence during the long term is lower than
average...particularly regarding amplification of the upper level
pattern by Mon-Tue...and the overall evolution of a trough digging
across the eastern Continental U.S....and associated cold front and any
potential surface wave development along the front. 00z/17 models handle
this upper level trough and surface features quite differently...with
the 00z/17 GFS and gefs suggesting the trough develops with a more
positive tilt...with the surface front passing through sun nt-Mon...with
any possible surface wave development occurring well off the New England
coast...while the 00z/17 European model (ecmwf) indicates a more neutral tilt to the
evolving trough...with surface wave development occurring much closer
to the northern middle Atlantic coast. So...the GFS/gefs would favor a
round of showers with the front sun nt/early Monday...while the European model (ecmwf)
would suggest a soaking rain across the region for Monday-Monday nt. At
this time...have generally favored the GFS/gefs Mode...as this more
vigorous wave development in the European model (ecmwf) seems to have changed rather
drastically from recent model runs.

Here are some more specific details...

Friday nt-Sat nt...it appears that low level moisture will advect
across the region from the south...allowing for quite a bit in the
way of low clouds to develop...especially Sat-Sat nt. So will trend sky
conditions to mostly cloudy for most areas. Some showers may occur
Sat-Sat nt mainly across the southern Adirondacks...where a
combination of warm advection and some orographic effects may
squeeze out the increasing atmospheric moisture. It also could
become quite breezy Sat afternoon...as a low level jet translates
across the region. Expect min temperatures to fall into the 40s for Friday nt
with some 30s across portions of the Adirondacks...then warming to
the 50s for most areas Sat nt. Sat maximum temperatures should reach the middle
60s to lower 70s...warmest in the Hudson River valley south of
Albany.

Sun-Mon...will gradually increase probability of precipitation Sun afternoon into sun
nt...then gradually taper on Monday from northwest to southeast as the front passes
through. Should the 00z/17 European model (ecmwf) prove correct...then Monday could be
much wetter...with a widespread soaking rain possible. Sun maximum temperatures
should reach the middle 70s in valleys...and 60s to lower 70s across
most higher elevations...with temperatures falling into the Lower/Middle 50s
in most areas for sun nt/Monday am. On Monday...expect maximum temperatures to range
from the upper 50s across the western Adirondacks...to the lower 70s
across the middle Hudson Valley and southern Litchfield Colorado CT.
However...again...if a steadier rain were to occur...maximum temperatures could
be much cooler.

Monday nt-Tue...much cooler air should infiltrate into the region from
the north and west. As the upper level trough slowly passes
through...expect isolated/scattered rain showers to occur...most
numerous across the southern Adirondacks and Mohawk Valley region.
Monday nt/Tuesday am mins should fall into the 40s in most areas...with Tuesday
maximum temperatures ranging from the Lower/Middle 60s within the Hudson
Valley...to the 50s across higher elevations...with some of the
highest peaks of the Adirondacks possibly only reaching the 40s.

&&

Aviation /12z Wednesday through Sunday/...
high pressure will continue to build in from the west today and
tonight. A cold front will approach from the northwest on Thursday.

Any fog/stratus should lift between 12z-14z/Wed...giving way to VFR
conditions for the rest of Wednesday into Wednesday evening. Some patchy
ground fog may develop once again after 05z/Thu...especially at kgfl and
kpsf...where some IFR/LIFR conditions could intermittently develop.

Winds will become west to southwest by middle morning 5-10
knots...becoming light/variable once again toward and after sunset.

Outlook...

Thursday night: no operational impact. No sig weather.
Friday: no operational impact. No sig weather.
Friday night: no operational impact. No sig weather.
Saturday: low operational impact. Breezy. No sig weather.
Saturday night: no operational impact. No sig weather.
Sunday: moderate operational impact.Breezy chance of rain showers.

&&

Fire weather...
outside of an isolated light rain shower or two Thursday...dry
weather is expected through Friday night. The next chance for
showers arrives over the weekend.

Daytime minimum relative humidity values generally between 40 and 50 percent
today and Friday with maximum relative humidity values generally between 75 and
95 percent tonight and Thursday night.

&&

Hydrology...
no widespread Hydro problems are expected for the remainder of this
week. The next chance for showers arrives this
weekend...however...amounts are expected to have minimum impacts
to the area river and streams.

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.

&&

Climate...
cold night on tap for this Thursday night into Friday morning.

Here are some record low temperatures for September 19th...

Albany ny: 32 degrees in 1959 (records date back to 1874)
current forecast: 39

Glens Falls ny: 31 degrees in 1995 (records date back to 1949)
current forecast: 34

Poughkeepsie ny: 33 degrees in 1990 (records date back to 1949...
however data is missing from January 1993 - July 2000)
current forecast: 44

&&

Aly watches/warnings/advisories...
CT...none.
New York...none.
Massachusetts...none.
Vermont...none.

&&

$$
Synopsis...bgm
near term...gjm/bgm
short term...bgm
long term...kl
aviation...gjm/kl
fire weather...iaa/bgm
hydrology...iaa/bgm
climate...iaa/bgm

For the latest updates...please visit our webpage at
www.Weather.Gov/Albany

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