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Area forecast discussion 
National Weather Service Albany New York
952 am EDT Sat Jul 23 2016

Synopsis...
very warm temperatures will continue today, but with slightly
lower humidity levels. An upper level disturbance will bring
isolated to scattered showers and thunderstorms, especially from
the capital district northward. It will turn cooler and less humid
for Sunday, with high pressure building in. Very warm
temperatures, increasing humidity and chances for showers and
thunderstorms return for Monday as a frontal boundary approaches
from the west.

&&

Near term /until 6 PM this evening/...
as of 945 am EDT...bright sunny start to this Saturday as
temperatures have quickly jumped well into the 70s and lower 80s.
Per the 12z soundings, our forecast highs look in good shape with
mainly 80s to some lower 90s as dewpoints generally hold between
60-65f. However, a fairly active convective day shaping up due to
a potent upper level short wave trough and jet Max over the upper
Great Lakes that will be moving through the region this afternoon.
Favorable left exit region of the upper jet Max places best
forcing and greatest coverage from around Albany northward.
Expecting isolated to scattered showers and thunderstorms to
develop from early to mid afternoon mainly for areas from I-90 and
the capital district northward. Hi-res models such as the
hrrr/hrrrx and the NSSL 4km WRF depicting this scenario.

The Storm Prediction Center continues to outlook much of our area
in marginal risk for severe storms today. This seems reasonable
given the relatively fast northwest flow inverted-v forecast
sounding profiles with a well-mixed low level environment.
Limiting factor is question of how much instability can develop to
support enough buoyancy to maintain updrafts given strong flow.
Generally thinking around 1000-1500 j/kg of SBCAPE seems
reasonable based on ncar 10-member WRF ensemble. Main threat
today will be strong wind gusts, although some small hail cannot
be ruled out and will continue to mention in the forecast.

Very warm temperatures expected again this afternoon, although it
will be "cooler" than Friday, with highs in the mid 80s to lower
90s in most valley locations. Humidity levels will be slightly
lower today, with dewpoints generally in the lower to mid 60s. A
northwest breeze around 10-15 mph will persist through much of the
day, with gusts stronger near thunderstorms.

&&

Short term /6 PM this evening through Monday night/...
convection should diminish rather quickly after sunset this
evening, as the aforementioned disturbance moves east into New
England and instability decreases due to loss of diurnal heating.
Large scale subsidence will increase overnight, as a ridge of high
pressure at the surface and aloft builds in from the Great Lakes.

Sunday will feature plenty of sunshine and dry conditions as the
ridge moves overhead. Winds will be lighter than Saturday, with
noticeably lower humidity levels as dewpoints drop into the 50s.
Temperatures will still be slightly above normal, but with the
lower humidity.

Clouds will then gradually increase Sunday night, as a warm front
approaches from the Ohio Valley. A few showers with a rumble of
thunder will be possible late across areas mainly north and west
of the capital district, but much of the area will remain dry.

Monday looks to have a better chance for showers and
thunderstorms, as a weakening cold front approaches from the west.
The degree of cloud cover and resulting instability is highly
questionable at this time, so while some strong to severe storms
cannot be ruled out it is quite uncertain how the convection will
evolve. Moisture return will be fairly robust, with dewpoints
creeping towards 70 during the afternoon and precipitable waters rising to
around 1.75 inches. Any storms could produce locally heavy
rainfall, but will mention only chance pops at this time due to
uncertainty with coverage/timing. With hot temperatures and
humidity returning, heat indices could approach 100 degrees in the
Mid Hudson valley, so will mention this in the severe weather potential statement.

&&

Long term /Tuesday through Friday/...
guidance is in agreement that the flow will be rather flat/zonal
across the region through the middle of the week with an upper
level low over hudson's Bay with short waves rotating about.
Expecting fair weather with highs running 5 to 10 degrees above
normal and lows only a bit above normal.

A trough is expected to develop as we end through the latter part
of the week into the weekend as a stronger short wave rotates
about the upper low as it moves gradually eastward and additional
short wave energy enters the flow from the Pacific northwest. The
upper flow is expected to end up paralleling surface boundaries
and waves of low pressure are then expected to move along the
boundaries. At this time it appears a boundary should end up
located to our south across the mid-Atlantic region with another
moving in from the northwest which is anticipated to become nearly
stationary over our region back across the Great Lakes region.
This set up will result in unsettled weather and a low confidence
forecast as the timing of the individual short waves varies
amongst the guidance and will impact the forecast. Have chances
pops for Thursday through Friday. The amount of instability that
will be present is very uncertain also as it be highly dependent
on the amount of cloud cover.

&&

Aviation /14z Saturday through Wednesday/...
isolated to scattered showers and thunderstorms are expected
across a portion of the local area generally along and to the
north of Interstate 90 during the afternoon as yet another short
wave trough approaches and moves across the region. Have indicate
threat for convection in kgfl and kalb tafs with vcsh. The better
chances for storms will at kgfl. Do not have the confidence due to
the potential coverage to include a direct mention in taf at this
time. Have no mention in kpou and kpsf tafs as activity should be
to the north especially for kpou.

Outside any convection VFR conditions are expected through the
evening with MVFR fog developing overnight.

Westerly winds will increase with gusts in the teens to lower
20s. Winds will shift more to the northwest this afternoon. Winds
will weaken in the evening becoming light and variable to calm for
the overnight.

Outlook...

Sunday to Sunday night: no operational impact. No sig weather.
Monday: moderate operational impact. Scattered rain showers...tsra.
Monday night: moderate operational impact. Chance of rain showers...tsra.
Tuesday: no operational impact. No sig weather.
Tuesday night: no operational impact. No sig weather.
Wednesday: no operational impact. No sig weather.

&&

Fire weather...
very warm temperatures will continue today, but with slightly
lower humidity levels. An upper level disturbance will bring
isolated to scattered showers and thunderstorms, especially from
the capital district northward. It will turn cooler and less humid
for Sunday, with high pressure building in. Very warm
temperatures, increasing humidity and chances for showers and
thunderstorms return for Monday as a frontal boundary approaches
from the west.

Minimum relative humidity values will be around 35 to 50 percent
this afternoon, increasing to between 90 and 100 percent late
tonight. Relative humidity values will drop to around 30 to 40 percent Sunday
afternoon.

Winds today will be northwest around 10 to 15 mph with gusts to
20 mph, decreasing to 5 to 10 mph tonight. Winds on Sunday will be
northwest at 5 to 10 mph.

&&

Hydrology...
isolated to scattered showers and thunderstorms are expected from
around the capital district northward this afternoon, with brief
local downpours. Basin-average rainfall will be light due to
limited coverage.

Dry weather is expected tonight through Sunday, although another
cold front will bring additional chances for showers and
thunderstorms late Sunday night into Monday.

Dry conditions return for Tuesday and Wednesday as high pressure
builds back into the region.

Flows continue to be below normal for mid to late July at many
locations in the Hydro service area, especially our western New
England counties.

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...
yesterday Friday, July 22nd was the warmest day of the Summer
across the local area with all 5 of our ASOS locations hitting 90+
degrees, even at Pittsfield Massachusetts.

Here is a look at the number of 90+ degree days so far this year,
what is normal and the most that has occurred in a year.

Albany ny:
2016: 8 days
normal: 10 days
most: 32 days in 1955
note: daily records date back to 1874

Glens Falls ny:
2016: 7 days
normal: 6 days
most: 22 days in 1988
note records date back to 1949

Poughkeepsie ny:
2016: 14 days
normal: 15 days
most: 30 days in numerous year most recently 2010, 2005 and 2002
note: records date back to 1949, however data is
missing from January 1993 through July 2000

Pittsfield ma:
2016: 1 day
normal: 2 days
most: 7 days in 2010
based on data dating back to 2000

Bennington vt:
2016: 2 days
normal: 3 days
most: 9 days in 2010
based on data dating back to 2000

&&

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

&&

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

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