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Area forecast discussion 
National Weather Service Albany New York
634 am EDT Tuesday Jun 30 2015

Synopsis...
cloud cover will be on the increase this morning as a warm front
approaches from the southwest. There will be chances for showers
and thunderstorms during the day today as the front gets closer to
the area. Unsettled weather will continue tonight into Wednesday...as
a low pressure system and a cold front bring more chances for showers
and thunderstorms to the area.

&&

Near term /until 6 PM this evening/...
as of 615 am EDT...an area of low pressure was located over the
east end of Lake Erie lifting a warm front northward from central
and western Pennsylvania. Middle and upper level southwesterly flow
sets up over New York and New England ahead of the warm front and short-
wave trough. The showalter indices go slightly negative in the
18z/Tue-00z/Wed time frame. Thus have thunderstorms mentioned for
this afternoon with just chances for showers beforehand.

Sb convective available potential energy are rather limited today with only a few hundred j/kg
this after. There will also be lots of clouds around too...which
coupled with weak middle level lapse rates should limit any severe
threat for today. Expect highs to be in the middle 70s to lower 80s.

&&

Short term /6 PM this evening through Thursday night/...
for tonight...the warm front attempts to cross the region during
this time frame...but it may get hung up just south and west of
the Mohawk Valley and the capital region. The lead short-wave
moves north and west of the forecast area...and low pressure will be
near southeast Ontario/SW Quebec. With the boundary hung up over and near
the forecast area...spokes of short-wave energy in the SW
flow...showers...and at least a chance of thunderstorms will
continue overnight. Precipitable waters look to rise back to close to 1.5
inches in the moister air mass. Some bursts of MDT-heavy rainfall
will be possible overnight. The higher probability of precipitation may actually shift
from the capital region south and east with the warm front trying
to move through. Lows will generally be in upper 50s to middle 60s.

Wednesday-Wednesday night...the parade of short-wave impulses moving through
the long-wave trough continues...with a short-wave trough swinging
through the neutral tilted upper level trough...causing it to
become negatively tilted...which may impact the region with some
strong thunderstorms /possibly severe/ during the middle-week in the
Wednesday to Wednesday evening time frame. A surface cold front
associated with low pressure moving over southern Quebec will be the
key focusing mechanism along with the short-wave. The big
question will be how much surface heating occurs like many situations
this year. The GFS is painting moderate instability values with
1000-2000 j/kg with surface dewpoints mainly in the 60s. The NAM is very
similar with sbcapes of 1000-1500 j/kg with slightly higher
amounts. The one notable difference is that the GFS does steepen
the middle level lapse rates in the 700-500 hpa layer to 6.0-6.6c/km
from the northern Catskills/capital region northward. The bulk shear
values increase in the 0-6 km layer to 35-50 kts with the short-
wave moving across the region and the cold front. Strong
thunderstorms are a possibility...maybe some scattered severe if
heating occurs ahead of the cold front. We will continue to the
enhance wording of some gusty winds/hail in the severe weather potential statement. The day 2
marginal category looks pretty good for now. Highs on Wednesday will
still be a little below normal for the first day of July with u60s
to l70s over the higher terrain..and middle to u70s over most of the
rest of the forecast area with some spotty lower 80s over the middle
Hudson Valley/northwest CT.

Wednesday night...the short-wave will pass early in the evening...as
well as the cold front. The showers and scattered thunderstorms will end
quickly in the early evening. Some drying is expected in the wake
of the front...with lows in the 50s to lower 60s over most of the
forecast area.

Thursday and Thursday night...will carry slight chance probability of precipitation on
Thursday with a dry forecast for Thursday night as high pressure
drops southeast from the upper Great Lakes Thursday morning and is
centered over western New York by late Thursday night. Expect highs on
Thursday to be in the upper 60s to upper 70s with lows Thursday
night in the middle 40s to lower 60s.

&&

Long term /Friday through Monday/...
it appears that rising middle/upper tropospheric heights and surface high
pressure will be the main highlights during this portion of the
forecast...although subtle smaller scale disturbances will still
need to be watched.

For Friday-Friday nt...it appears that a frontal system should settle far
enough south of the region so that any potential wave development
and possible clouds/showers should remain across the middle Atlantic
region...with generally fair conditions across much of the northeast
states. Temperatures will be a bit below normal...with maxes generally
reaching 75-80 in valleys...and 70-75 across higher elevations. Friday
nt/Sat am mins will be cool...mainly in the 50s.

Sat-Sat nt...although the general trend of models and their
ensembles have trended farther south with precipitation from last night/S
cycle...there are still some hints that a smaller scale
disturbance...or perhaps an interaction between a northern impulse
and some moisture from the south could impact the region Sat
afternoon or evening. Will trim back the probability of precipitation a bit...but still keep
low chance probability of precipitation for most areas Sat afternoon-evening for scattered
showers/tstms...although future forecasts may continue to trend more
optimistic if forecast models continue to suggest less interaction
between impulses/moisture. Temperatures should remain a bit below
normal...mainly in the 70s for highs and middle 50s to around 60 for
Sat nt/sun am mins.

Sun-Mon...it appears that in the wake of any potential upper level
disturbance passage...high pressure and rising middle/upper level
heights should return for sun-Mon. This should allow for generally
fair weather...with temperatures returning to more seasonable levels...with
maximum temperatures in the lower 80s in valleys and 75-80 across higher
elevations...and overnight mins sun nt/Monday am ranging from the middle
50s across higher elevations...to the lower 60s in valleys.

&&

Aviation /12z Tuesday through Saturday/...
a warm front will approach from the southwest this afternoon and
tonight. Middle level clouds will increase this morning and continue
into this afternoon/night...along with scattered showers...mainly
this afternoon into Tuesday night.

Some lingering ground fog should lift at kpsf through
13z/Tue...with LIFR/IFR trending to VFR. Elsewhere...VFR
conditions are expected through at least 15z/Tue. An area of
showers currently across south central New York state will move
northeast...and may approach kgfl between 14z-16z...and kalb
between 15z-17z...while remaining mainly west and north of kpou
and kpsf. There could be some visibility reductions into the MVFR range
with these showers...with the best chance of such visibility reductions
at kgfl.

Once this initial batch of showers passes by...additional
scattered showers are expected to develop this afternoon...especially at
kgfl and kalb. Several rounds of showers will then be possible
into the overnight hours...and should expand to all taf sites
overnight. Occasional MVFR/IFR visibilities could develop within these
showers.

Also...as the low levels of the atmosphere moisten...areas of
MVFR/IFR visibilities and especially ceilings should develop after 08z/Tuesday
outside of any showers.

The chances for thunder look fairly low this afternoon...although
can not completely rule out some embedded rumbles of thunder. Will
not include any mention of thunder at this time as overall
probability is too low...but will remain vigilant for possible
inclusion in subsequent taf issuances/updates.

Light/variable winds will trend into the south by middle morning and
increase to 5-10 knots. Some gusts into the 15-20 knots range could
occur at kalb. Winds will remain from the south to southeast after
sunset...at generally less than 10 knots.

Outlook...

Wednesday night: moderate operational impact. Chance of rain showers.
Thursday: low operational impact. Slight chance of rain showers...tsra.
Thursday night: no operational impact. No sig weather.
Friday: no operational impact. No sig weather.
Friday night: no operational impact. No sig weather.
Independence day: moderate operational impact. Scattered rain showers...tsra.
Saturday night: low operational impact. Isolated rain showers.
Sunday: no operational impact. No sig weather.

&&

Fire weather...
cloud cover will be on the increase this morning as a warm front
approaches from the southwest. There will be chances for showers
and thunderstorms during the day today as the front gets closer to
the area. Unsettled weather will continue tonight into Wednesday...as
a low pressure system and a cold front bring more chances for showers
and thunderstorms to the area.

&&

Hydrology...
a brief period of dry weather will end this morning as unsettled
weather returns to our region and lasts through Wednesday.

The chances of showers and thunderstorms will increase by this
afternoon and continue into Wednesday. Some of the thunderstorms
may produce locally heavy rainfall late this afternoon into
Wednesday...but overall widespread Hydro problems are not expected
aside from ponding of water on roadways...and isolated poor
drainage flooding of low lying or urban areas. Total rainfall
through Wednesday looks to be in the half inch to inch range.
Locally higher amounts are possible with any convection.

A period of drier weather potentially returns late in the week to
open the Holiday weekend.

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...
June precipitation through 4 PM June 29 (departure from normal)

Albany ny: 6.63 inches (+2.96 inches)
glens falls: 5.87 inches (+2.44 inches)
Poughkeepsie ny: 4.03 inches (-0.27 inches)
Bennington vt: 2.93 inches (-1.08 inches)
Pittsfield ma: 8.03 inches (+3.74 inches)

Albany needs more 0.21 inches to make it into the top 10 wettest
junes since 1826. The wettest is 8.74 inches set back in 2006.

June 2015 is already the 7th wettest for Glens Falls since 1949.
The wettest is 8.20 inches set back in 1998.

Poughkeepsie needs more 1.23 inches to make it into the top 10
wettest junes since 1949. The wettest is 9.82 inches set back in
2013.

&&

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

&&

$$
Synopsis...iaa/11/wasula
near term...11
short term...11/wasula
long term...kl
aviation...kl
fire weather...11
hydrology...11
climate...

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