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Area forecast discussion 
National Weather Service Albany New York
1011 PM EDT Thursday Aug 28 2014

Synopsis...
high pressure positioned across the Great Lakes region
tonight...will build into the northeast on Friday. This high will
move over eastern New York and western New England by Friday
afternoon...with fair and dry weather to close the work week. High
pressure will then move offshore Friday night into Saturday...with a
return southerly flow of more humid air moving into the region
during the Holiday weekend. There will be increasing chances for
showers and thunderstorms by Sunday...as a slow moving cold front
approaches.

&&

Near term /until 6 am Friday morning/...
as of 1000 PM EDT...latest Sat picture showing clouds still
holding on. Will adjust clouds and hourly temperatures a tad to align with
latest surface observation. It will be a chilly night once we clear out and
colder and drier air takes hold. Temperatures will start to fall
as skies clear out overnight.

Winds speeds will gradually decrease overnight...but there will
still be a slight breeze for many locations most of the night with
the surface high positioned just to our west. Winds should become
near calm around sunrise...which will allow temperatures to drop
into the 40s and lower 50s in the dry air mass. Will also mention
patchy fog in favored sheltered valleys and locations near bodies
of water.

&&

Short term /6 am Friday morning through Saturday night/...
high pressure will be positioned over the region on Friday...which
will provide subsidence for abundant sunshine and light winds with
just a few fair weather cumulus around. Humidity levels will remain
comfortable...with dewpoints expected to be in the upper 40s to
lower 50s. After a cool start to the day...temperatures will rebound
in the 70s across the region which will average a few degree below
normal. Mainly clear skies to start the evening...but clouds will
gradually increase Friday night as a southwest flow aloft Ushers in
some middle and high level clouds. With the increasing
clouds...temperatures will not be as cool as Thursday night with
mainly lower to middle 50s expected.

It looks like we will have one more rain-free day on Saturday...as
high pressure moves further offshore and the ridge axis aloft shifts
eastward into New England. Model guidance indicating a stable and
capped environment...so will keep the forecast dry through the day.
Some middle and upper level moisture will be around...but we are
thinking skies should still average partly sunny. Humidity levels
will start to increase due to low level southerly flow...but should
not be too uncomfortable just yet. Maximum temperatures expected to be near or
slightly above normal.

Chances for showers and thunderstorms will start to increase
Saturday night...especially north and west of the capital
region...as a frontal boundary approaches from the St Lawrence River
valley. Models depicting a rather weak system with not much upper
level support...so will only mention slight chance to chance probability of precipitation
for now. Temperatures will be much milder with thickening clouds and
increasing humidity levels...with lower to middle 60s expected
region-wide.

&&

Long term /Sunday through Thursday/...
an upper level shortwave trough will be lifting from the Great Lakes
towards the northeast on Sunday. This feature will be weakening as
it will be running into an upper level ridge along the eastern
Seaboard of the US. The surface cold front associated with this
shortwave will be lingering back to the west across the Great Lakes
and southern Canada.

The result will be a warm and humid day on Sunday. There will
probably be a lot of clouds...with some breaks of sunshine from time
to time. Some showers and thunderstorms will be possible...especially
during peak heating of the aftn/eve...with the best chance for areas
north/west of the capital region and closer to the synoptic forcing.
Maximum temperatures look to be in the middle 80s for valley areas...with highs in
the middle 70s to low 80s for the hills/mountains.

The threat for showers and thunderstorms will continue for Sunday
night and into early next week with lots of clouds around. The
frontal boundary to our west on Sunday night will wash out as it
runs into the upper level ridge...and it will take until a stronger
front is able to move through the region by middle week to finally end
the threat for scattered showers and thunderstorms. With 850 hpa
temperatures around +15 to +18 degrees c...it will be a fairly warm and
muggy week...with daytime highs in the 80s...and low in the 60s. We
will continue to go with a chance for showers/thunderstorms through
Tuesday night...with the best chance during the afternoon/evening hours.

By Wednesday...a cold front will have moved through and cooler and
drier air will be working into the region. Maximum temperatures will be closer
to normal /upper 70s to near 80/ for valley areas.

&&

Aviation /02z Friday through Tuesday/...
VFR conditions are expected across the taf sites through Friday
evening. Low to middle level clouds will dissipate tonight with the
loss of daytime heating. Winds will start to diminish to less than
5kts after 04z.

Will continue to forecast some IFR fog at kgfl...and possibly kpsf
as well...after 06z-08z until about sunrise. Fog looks less
possible at kpou/kalb due to dry low levels and/or a lingering
breeze.

VFR conditions will be in place on Friday. Ceilings will generally
be few-sct050. Surface winds will be light out of the north 5kts or less.

Outlook...

Friday night: no operational impact. No sig weather.
Saturday: no operational impact. No sig weather.
Saturday night: low operational impact. Slight chance of rain showers...tsra.
Sunday: moderate operational impact. Chance of rain showers...tsra.
Sunday night: moderate operational impact. Chance of rain showers...tsra.
Labor day: moderate operational impact. Chance of rain showers...tsra.
Monday night: low operational impact. Slight chance of rain showers...tsra.
Tuesday: moderate operational impact. Chance of rain showers...tsra.

&&

Fire weather...
high pressure positioned across the Great Lakes region
tonight...will build into the northeast on Friday. This high will
move over eastern New York and western New England by Friday
afternoon...with fair and dry weather to close the work week. High
pressure will then move offshore Friday night into Saturday...with a
return southerly flow of more humid air moving into the region
during the Holiday weekend. There will be increasing chances for
showers and thunderstorms by Sunday...as a slow moving cold front
approaches.

Relative humidity values will increase to around 85 to 100 percent
tonight...then drop to minimum values of between 40 and 50 percent
Friday afternoon. Maximum relative humidity values Friday night are expected to be
around 85 to 100 percent.

Northwesterly winds will decrease to around 5 miles per hour tonight. Winds
will become northerly around 5 miles per hour on Friday...before shifting to
the south Friday night.

&&

Hydrology...
no widespread Hydro problems are expected on the main Stem rivers
through the next 5 days.

Another stretch of dry weather is expected through Saturday...as
high pressure returns to the region and then moves offshore to start
the weekend. The main Stem rivers will continue to slowly recede
into Saturday.

A slow moving cold front near the St Lawrence River valley will
focus scattered showers and thunderstorms Sunday into Labor Day in a
much more humid air mass. The threat for locally heavy rainfall with
any thunderstorms will increase during this time.

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...vtk/jpv
near term...vtk/jpv
short term...jpv
long term...frugis
aviation...vtk
fire weather...jpv/wasula
hydrology...jpv/wasula

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