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fxus61 kaly 222352 
afdaly

Area forecast discussion
National Weather Service Albany New York
752 PM EDT Mon may 22 2017

Synopsis...
a low pressure system will move off to our east tonight and
higher pressure will begin to build in. The high will dominate
our weather through Wednesday with fair weather and seasonable
temperatures. The weather will turn unsettled for the latter
part of the week as a slow moving low pressure system approaches
and moves across the region bringing a widespread rainfall to
the area.

&&

Near term /until 6 am Tuesday morning/...
as of 752 PM EDT...a weakening occluded front is in the process
of crossing our far eastern zones at this time. A band of
frontal rain showers is just exiting Berkshire and Litchfield
County, which should now mostly end the chance for rain showers
for tonight. However, plenty of clouds look to remain tonight
thanks to little low-level flow and lots of low-level moisture
remaining in place. Infrared satellite imagery shows plenty of clouds
remaining upstream as well, although most of these clouds are
mid and high level in height. If any breaks do occur, some
radiational fog may form in some spots late tonight as well.

Lows will generally be in the 40s, with the lowest readings over
the Adirondacks and southern Vermont.

&&

Short term /6 am Tuesday morning through Wednesday night/...
weak ridging will build in at the surface Tuesday and is
expected to remain over the area through Wednesday with fair
weather and seasonable temperatures. Guidance has come into
better agreement having a weak Low Pass well south off Long
Island Tuesday night into Wednesday with its associated
precipitation remaining well to our south and east. Aloft
some ridging will be induced over the region in advance of a
deepening trough to our west across the central Continental U.S.. a low
pressure system will develop over the Tennessee/Ohio valleys in
response to the deepening trough. An upper low is expected to
develop Wednesday night as vigorous short wave energy rotates
about the base of the trough resulting in a nearly vertically
stacked system. Chances for showers will be on the increase
late Wednesday night as the system gradually approaches. There
are indications that secondary development may occur over the
Delaware-Maryland-Virginia region as the upper trough begins to become negatively
tilted.

Expecting seasonable warm temperatures during the day both
Tuesday and Wednesday along with light winds.

&&

Long term /Thursday through Monday/...
confidence continues to grow in an unsettled pattern impacting
Memorial Day weekend. We start off with an amplifying trough from
the Midwest moving into the northeast as a coastal low from the
Gulf moves up the East Coast Thursday. Just how much rainfall
we receive in addition to the potential for any thunderstorms
will be contingent upon how far north the system's warm front
travels. Past few days guidance shows the front only getting up
to NYC/coastal CT which keeps the majority of our County Warning Area out of the
warm sector. BUFKIT soundings only show limited elevated
instability in our far southern and eastern spots so put the
threat for thunder there. Still not certain on system's exact
speed but thinking that Thursday afternoon should be wetter than
the morning as showers move into our area from southwest to
northeast through the day Thursday. Given impressive 850mb jet
over eastern part of County Warning Area and decent packing of isotherms, some
steadier periods of rain are possible.

By Thursday night, a dry slot should wrap into the low and provide
breaks of dry time; however, given that the upper level low should
still near the area, kept likely probability of precipitation in the area. Diurnal
heating in addition to the upper level low cutting off and
moving over the northeast should allow showers to resume during
the daytime Friday so continued likely pops. The trough axis
should exit the area Saturday so lowered probability of precipitation in South/West
counties but kept chance pop North/East. Ridging builds in for
the daytime Saturday so it should end by being a pleasant day
for most areas.

Watching another mid latitude cyclone moving into the Great
Lakes/northeast for Sunday/Monday. Given this is a week away, do not
have high confidence on exact timing of precipitation. Current
guidance suggests that the first half of Sunday should feature dry
time under increasing clouds before the threat for showers increase
late in the day into Monday.

Temperatures for the extended should average near to slightly below
normal with highs in the upper 60s to low-mid 70s most days and
above average precipitation amounts due to the unsettled pattern.

&&

Aviation /00z Tuesday through Saturday/...
occluded front is through the region, ending the threat for
widespread rain showers. However, abundant low level moisture
remains in place. This low-level moisture will allow for some
low MVFR/IFR stratus this evening, especially at kpsf/kpou.
Some clearing will eventually make its way into the region,
allowing for some of the lower clouds to clear out by around
midnight or so. However, this clearing may result in radiational
fog forming for later tonight, which may keep IFR conditions
for most sites for the late night hours. Kalb may only drop to
MVFR, as a larger T/dew point spread and a light breeze may prevent IFR
conditions from occurring there. Otherwise, winds will become
light from a west to northwest direction for the overnight
hours.

Any morning mist or low clouds should quickly dissipate after
sunrise due to the strong late may sunshine. VFR conditions are
then expected through the entire day on Tuesday with just some
passing high cirrus clouds and light north to northwest winds at
5 kts or less.

Outlook...

Tuesday night: no operational impact. No sig weather.
Wednesday: no operational impact. No sig weather.
Wednesday night: moderate operational impact. Chance of rain showers.
Thursday: high operational impact. Likely rain showers.
Thursday night: high operational impact. Likely rain showers.
Friday: high operational impact. Likely rain showers.
Friday night: low operational impact. Slight chance of rain showers.
Saturday: low operational impact. Slight chance of rain showers.

&&

Fire weather...
a low pressure system will move off to our east tonight and
higher pressure will begin to build in. The high will dominate
our weather through Wednesday with fair weather and seasonable
temperatures. The weather will turn unsettled for the latter
part of the week as a slow moving low pressure system approaches
and moves across the region bringing a widespread rainfall to
the area.

&&

Hydrology...
a low pressure system will move off to our east tonight and
higher pressure will begin to build in. The high will dominate
our weather through Wednesday with fair weather. The weather
will turn unsettled for the latter part of the week as a slow
moving low pressure system approaches and moves across the
region bringing a widespread rainfall to the area.

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
near term...frugis
short term...iaa

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