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fxus61 kaly 270753 
afdaly

Area forecast discussion
National Weather Service Albany New York
353 am EDT Sat may 27 2017

Synopsis...
a milder start to this Holiday weekend under variable cloud
coverage and mainly dry conditions. The next chance for wet
weather arrives Sunday night into Monday as a warm front lifts
northward across the region.

&&

Near term /until 6 PM this evening/...
as of 330 am...while most of the day should remain tranquil, a
couple of challenges remain. First will be the cloud coverage
and the second will be the approaching short wave late in the
day.

As far as cloud coverage, per the enhanced overnight imagery,
seems variable as pockets of overcast to clear conditions.
Meanwhile, convective complex was weakening as it transverses
east-southeast through Ohio into Pennsylvania. So the day a
partly sunny to mostly cloudy forecast. Hires numerical
reflectivity forecasts suggest some terrain based showers
developing as we do remain within a rather moist cyclonic flow
regime. Furthermore, the aforementioned approach of the upstream
short wave will add some additional lift across the dacks and
northern Warren County late in the day as well. For now, we will
place pops within the slight chance category and watch as trends
unfold though the day. High temperatures today should climb to
between 65-70f for valley locations with mainly low-mid 60s
elsewhere.

&&

Short term /6 PM this evening through 6 PM Sunday/...
the fast moving short wave tracks across northeast NY, then
through Vermont and New Hampshire this evening as we will hold onto the slight
chance pops for these areas through the evening hours. The
remainder of the overnight period, increasing subsidence as
short wave ridge axis slides across the entire region toward 12z
Sunday. As surface high transverses the region with moist ground
under partly cloudy skies at least, this will potentially bring
the possibility of fog as we will place this in the grids for
several locations overnight. Overnight lows will range from
45-55f across the County Warning Area.

Any sunshine we receive during Sunday will become increasingly
filtered through the day as the short wave ridge slides east of
the region with the approach of the warm front and convection
developing along and ahead of this boundary. This may be the
warmest day of the Holiday weekend with mainly dry conditions
and temperatures able to climb back into the 70s for valley
locations and 60s elsewhere. Marine influence air mass may
advect northward across the Mid-Hudson valley, eastern
Catskills into northwest CT through the day too as southerly low level
flow increases ahead of the approaching upstream warm front.

&&

Long term /Sunday night through Friday/...
an unsettled pattern looks to continue to be in place through much
of the extended period.

At the start of the period, a large closed off upper level low will
be moving from the northern plains and Canadian prairies towards the
western Great Lakes for Sunday night into Monday. Ahead of this
feature, weak shortwave ridging will be departing off the eastern
Seaboard with south to southwest flow in the low to mid levels
across our area. With increasing moisture advection and warm air
advection in place, a period of steadier rain showers looks to occur
for late Sunday night into much of the day on Monday. Steady precip
will be tapering off during the afternoon hours on Monday from west
to east, as the best moisture/lift shifts into eastern New England.
With the clouds and precip, temps will be on the cool side. Lows on
Sunday night will be in the upper 40s to mid 50s ahead of the
approaching precipitation and will only reach into the 60s for
Monday.

The upper level low will be slowly shifting eastward across the
Great Lakes region and Ontario on Tuesday into Wednesday. Ahead of
this feature, broad southwest flow will be in place. With 850 hpa
temps warming to around 10 degrees c, temps will be warmer on
Tuesday with highs well into the 70s. However, it will continue to
be fairly cloudy, with a partly to mostly cloudy sky. Another
approaching frontal boundary will allow for some additional
scattered showers and possibly a thunderstorm, especially during the
peak heating of the day. As the upper level low starts to get
closer, falling heights and temps aloft will allow for temps to be a
few degrees cooler on Wednesday, with valleys only reaching the
lower to middle 70s. However, there will continue to be a few more
showers around (especially for northern areas closer to the upper
level forcing) thanks to the moist cyclonic flow in place and still
plenty of clouds throughout the day.

By Thursday into Friday, the upper level low will be weakening and
shifting into Quebec. Still cannot rule out a few passing light
rain showers (mainly for northern areas) due to the continued
cyclonic flow, but coverage looks to be much less than earlier in
the week and there looks to be more breaks of sunshine compared to
earlier in the week as well. Highs will generally be in the low 70s
for valley areas, with 60s across the hills and mountains.

&&

Aviation /06z Saturday through Wednesday/...
ceilings will vary from MVFR to VFR before becoming
predominantly MVFR overnight. Ceilings at kpou may be VFR all
night. Ceilings will then rise into the VFR range after 13z-14z
at all taf sites.

Ceilings and visibilities are expected to be VFR Saturday
morning and afternoon. Kpsf will linger the longest with high
MVFR cigs until the late morning/early afternoon.

The winds will be generally light from the north to northwest
at 6 kt or less tonight. Light and variable direction winds of
5 kts or less are likely late Saturday morning into the early
afternoon.

Outlook...

Saturday night: no operational impact. No sig weather.
Sunday: no operational impact. No sig weather.
Sunday night: moderate operational impact. Chance of rain showers.
Memorial day: high operational impact. Likely rain showers...tsra.
Monday night: moderate operational impact. Chance of rain showers.
Tuesday: high operational impact. Likely rain showers...tsra.
Tuesday night: moderate operational impact. Chance of rain showers.
Wednesday: moderate operational impact. Chance of rain showers.

&&

Fire weather...
slightly warmer and drier Saturday with light northwesterly
winds. A bit warmer still on Sunday with light southerly winds.
Relative humidity values will bottom out in the 50s both days. Showers and a
few thunderstorms become likely Sunday night into Memorial Day.

&&

Hydrology...
mainly dry weather is expected this weekend. An approaching
system will bring the likelihood of showers and a few
thunderstorms Sunday night into Memorial Day, with total quantitative precipitation forecast
ranging from 0.25-0.75" expected. Additional periods of showers
and thunderstorms are likely Tuesday and Wednesday.

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.

&&

Equipment...
the ASOS in Glens Falls at the Floyd Bennett Memorial Airport
and Pittsfield Airport, Massachusetts continues to experience outages with
hourly metars occasionally missing. This will continue until
communications are fully restored.

&&

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

&&

$$
Synopsis...bgm
near term...bgm
short term...bgm
long term...frugis
aviation...frugis/bgm
fire weather...bgm/Thompson

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