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Area forecast discussion 
National Weather Service Albany New York
622 am EDT Thursday Aug 25 2016

Synopsis...
a warm front approaching from the west will bring some scattered showers
and thunderstorms, along with humid conditions, to the region
today into this evening. On Friday, isolated to scattered showers
and thunderstorms are possible again ahead of a cold front. Fair
and warm conditions are forecast for Saturday as high pressure
moves across the area.

&&

Near term /until 6 PM this evening/...
mostly clear sky over much of the region early this morning. The
leading edge of cloudiness is into the western Mohawk Valley and
southern Adirondacks. A few isolated showers and sprinkles are
just beginning to approach those areas as well. Based on
satellite and radar, showers are tending to dry up as they head
east but better coverage and intensity of showers further west of
Syracuse and that is what will give our area better chances of
showers and possible thunderstorms this afternoon.

Mesoscale model guidance suggests some isolated showers could get
to the eastern Catskills to central Mohawk Valley through the Lake
George Saratoga region by midday. If showers do make it that far
east, there should be breaks of sun outside of the showers. By
afternoon, better coverage of scattered showers and thunderstorms
are expected as the leading edge of a warmer and more humid
airmass provides some low level forcing.

The showers and thunderstorms in the Ohio/PA area are the remnants
of what brought the tornadoes to Indiana yesterday but the low
level wind fields, shear and instability are expected to be
considerably less in our region than what the Indiana area
experienced yesterday. So, while there may be some scattered
strong storms this afternoon, no severe weather is expected as
convective available potential energy maximize between 1000-1500 j/kg, low level jet energy
should not exceed 25-30 kt and cumulative 0-6 km shear around 40
kt.

The Morning Sun and periods of sun in the afternoon will help
temperatures to reach solidly into the 80s, with around 80 in
higher terrain.

&&

Short term /6 PM this evening through Saturday night/...
any lingering showers and storms will end during the evening but
there are indications that another cluster of convection that is
currently in the Midwest, will track out of the OH valley and
through mainly central and southern New York. The convection is timed
for around midnight and the early morning hours of Friday and
there is some question as to whether it holds together well into
southern VT, the Berkshires and northwest CT. Indicating a little increase
in coverage of scattered showers and storms after midnight in many
areas and by daybreak Friday confining best chances to eastern and
southern areas.

The low level wind shift boundary is expected to cross through our
area by early Friday afternoon, while the dewpoint boundary is
timed to exit our region Friday afternoon and evening. There could
be some isolated showers and thunderstorms, mainly in southern
areas to northwest CT and the southern Berkshires. Sky cover should
improve through the day but boundary layer temperatures should not
fall much.

Highs Friday in the upper 80s to lower 90s but cooler in higher
terrain. Dry weather is expected Saturday and Saturday night as
high pressure builds in with highs in the mid to upper 80s
Saturday but again a dryer atmosphere.

&&

Long term /Sunday through Wednesday/...
as of 330 am EDT/Thursday, it appears that much of the long term
portion of the forecast will be dominated by anomalously high
mid/upper tropospheric heights, and above normal temperatures. A few
passing shortwaves around the northern periphery of a strong upper
level ridge over the southeast U.S. May bring scattered
showers/thunderstorms late Sunday into Monday, and then again
possibly Wednesday night or Thursday. Also, will need to follow
trends on potential tropical entity over the southeast U.S and/or
Gulf Coast region, as some moisture from this system could
eventually become entrained in a passing northern stream system
toward the end of the long term period.

As for thunderstorm chances, it appears Sunday-Sunday night across
northern areas will have the best overall possibility which should
be in closer proximity to overall upper level dynamics of a passing
shortwave. As is always the case with shortwaves passing on the
northern periphery of such anomalously strong mid/upper tropospheric
ridges, will have to watch instability and wind shear parameters
closely, as there could be some relatively fast moving organized
convection, ultimately depending on these two factors.

With h500 heights exceeding 590 dm, have forecasted temperatures
warmer than superblend guidance for Sunday, with highs between 85-90
in valleys, and generally 80-85 across higher elevations. If a
southwest low level wind flow occurs, and clouds/convection are
delayed, some lower elevations could even exceed 90. Warm and humid
for Sunday night, with lows mainly in the 60s to lower 70s.

For Monday-Thursday, still warm but slightly less humid, with highs
mainly in the lower/mid 80s across lower elevations, and 75-80
across higher terrain. Overnight lows will mainly be in the 60s
across lower elevations, and 50s for the higher terrain.

&&

Aviation /10z Thursday through Monday/...
a weak warm front will approach from the west today, followed by
the approach of a cold front for tonight. Scattered showers and
embedded thunderstorms will be possible with these fronts
this afternoon into tonight.

Expect VFR conditions until possible bands of showers and
embedded thunderstorms develop and move eastward across the taf
sites mainly after 16z/Thu. Periods of MVFR/IFR vsbys/cigs will
be possible in heavier showers.

For tonight, there still could be isolated to scattered
showers/thunderstorms well into the evening hours. Otherwise,
areas of MVFR/IFR cigs/vsbys should develop after 02z/Fri given a
rather moist boundary layer. The best chance for sustained IFR
conditions should be at kpsf after 07z/Fri.

Winds will increase from the south to southwest winds at 8-12 knots
with occasional gusts up to 20-25 knots by late morning, especially
at kalb. Winds will remain from the south to southwest and
decrease to less than 10 knots after sunset.

Winds will be stronger, and variable in direction in and near
thunderstorms.

Low level wind shear has been included for kgfl/kpsf/kpou tafs
through around 13z as sfc winds remain less than 5 knots at these
locations, while winds around 2000 feet above ground level remain southwest at
25-30 kt, strongest at kgfl. The threat for low level wind shear
should decrease with greater mixing after 13z/Thu.

Outlook...

Friday night: no operational impact. No sig weather.
Saturday: no operational impact. No sig weather.
Saturday night: no operational impact. No sig weather.
Sunday: no operational impact. No sig weather.
Sunday night: moderate operational impact. Scattered rain showers...tsra.
Monday: low operational impact. Isolated rain showers...tsra.
Monday night: no operational impact. No sig weather.
Tuesday: no operational impact. No sig weather.

&&

Fire weather...
a warm front approaching from the west will bring some scattered showers
and thunderstorms, along with humid conditions, to the region
today into this evening. On Friday, scattered showers and
thunderstorms are possible again ahead of a cold front. Fair and
warm conditions are forecast for Saturday as high pressure moves
across the area.

The relative humidity values drop to 55 to 70 percent this afternoon with
scattered showers and thunderstorms. Relative humidity recovers to 80-100
percent again tonight with more scattered showers and
thunderstorms. A slight drying trend is expected Friday with
minimum relative humidity values 50 to 60 percent.

South to southwest at 5-10 mph through the early morning,
increasing to 10-15 mph this afternoon, and may occasionally gust
up to 20-25 mph late in the afternoon into tonight, especially in
north/south oriented valleys such as the Hudson Valley and also
across higher terrain. Winds shift to west and northwest at 15 mph
or less Friday.

&&

Hydrology...
scattered showers and thunderstorms are expected Thursday and
Friday. Most rainfall amounts should remain a half inch or less,
although locally higher amounts of over 1 inch will be possible
in thunderstorms. Localized ponding of water in low lying/poor
drainage and urban areas will be possible late this afternoon into
Thursday night in any heavier downpours.

Dry conditions are expected to return for Saturday into Sunday.

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...NAS
near term...NAS
short term...NAS
long term...kl
aviation...kl
fire weather...NAS
hydrology...NAS

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