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

Synopsis...
a warm front approaching from the west will bring some showers
and thunderstorms, along with humid conditions, to the region on
Thursday. On Friday, showers 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 am this morning/...
some areas of high clouds tracking through the region through
daybreak should not prevent at least some radiational cooling.
Showers in the Great Lakes slowly building east and there may be
an isolated shower by daybreak around the western Mohawk Valley
or southern Adirondacks. Just minor adjustments to the
temperatures and sky cover through daybreak. Lows mainly in the
lower/mid 60s, except for some 50s across higher terrain.

&&

Short term /6 am this morning through Friday night/...
for Thursday-Thursday night, a Theta-E ridge will be over the
area. The combination warmth, moisture, and upper level energy
should allow at least isolated/scattered showers to develop
Thursday. Pwats are forecast to approach 2 inches, so, locally
heavy downpours will be possible. Surface based instability
increases to around 1400 j/kg across the western Adirondacks and
Mohawk Valley late Thursday afternoon, and within portions of the
Hudson River Valley North of Albany, and less to the south and
east. It will be warm and humid, with daytime highs mainly in the
80s, and Thu night lows mainly in the 60s to lower 70s.

Friday-Friday night, a cold front will be slowly settling
southeast across the region Friday. Current timing suggests that
it passes through most areas north and west of Albany by midday, and
across southeast areas by late afternoon. Most of the upper level
support will lift well north and east of the region, with strong
upper level ridging building to the south. So, at this time, it
appears that only scattered showers and isolated thunderstorms
should precede/accompany its passage, with the best chance for
rain mainly from the southeast Catskills into the Berkshires, southeast VT, Mid
Hudson valley and Litchfield Colorado CT during the early-mid afternoon
hours. A wide range in temperatures expected on Friday with highs
across the western Adirondacks in the upper 70s and Max temps
reaching 85-90 in valley areas, perhaps even lower 90s across
portions of the Mid Hudson valley. Less humid for Friday night
with fair conditions, with lows mainly in the 60s across lower
elevations, and 50s for higher terrain.

&&

Long term /Saturday through Wednesday/...
the strong upper ridge centered over the southeastern United States
is expected to weaken as we head into and through early next week.
Also, a short wave moving along the United States/Canadian border is
expected to press into the ridge and move across the Great Lakes
region and northeast Sunday through Monday bringing a low pressure
system across the region. There are some timing and amplitude
differences amongst the models regarding this feature.

Ridging will be in control at the surface and aloft for at least the
for the first half of the weekend with fair and warm Summer weather
with highs ranging mainly from the mid 70s to mid 80s. The surface
high will shift eastward off the New England coast Sunday with
the upper ridge flattening. At this time it appears Sunday should be
another day with fair weather however will bit warm temperatures and
higher dew points.

Our next chances for rain will are expected Sunday night and Monday
as the low pressure system approaches and moves through. Despite the
passage of the cold/cool front temperatures will continue to be
warm. High pressure is anticipated to build back in at the
surface while the flow aloft remains flat so not sure how far south
the front will get before stalling.

&&

Aviation /05z 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
Thursday afternoon and night.

Through daybreak, tricky call on potential ground fog formation,
as winds near the top of the boundary layer will be increasing
overnight, which may aid in just enough dry air entrainment to
limit fog potential. It appears that there is a slight chance of
MVFR/IFR reductions due to fog/stratus between roughly 08z-11z/Thu
at kpsf, and perhaps a brief period at kgfl, with mainly VFR
persisting at kalb and kpou.

After daybreak, any isolated patches of low stratus/fog should mix
out by 13z/Thu. Expect VFR conditions until possible bands of
showers and embedded thunderstorms develop and move eastward
across the taf sites mainly after 20z/Thu. Periods of MVFR/IFR
vsbys/cigs will be possible in heavier showers.

For Thursday night, 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.

Winds will be mainly from the south to southwest at less than 5 knots
through daybreak, except at kalb where south winds should continue
at 5-10 kt, and may actually increase after 08z/Thu to 8-12 knots
with gusts up to 15-20 knots possible. After sunrise, expect south to
southwest winds at 8-12 knots and occasional gusts up to 20-25 kt,
especially at kalb. Winds will remain from the south to southwest
and decrease to less than 10 knots after sunset.

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

Outlook...

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

&&

Fire weather...
fair and warm weather will continue through this evening. A warm
front approaching from the west will bring some showers and
thunderstorms, along with humid conditions, to the region on
Thursday. On Friday, showers 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 increase to 80 to 100 percent tonight and drop to
45 to 65 percent on Thursday. Widespread heavy dew formation is
less likely tonight as some areas will maintain a south to
southwest wind overnight. Relative humidity recovers to 90-100 percent again on
Friday morning.

Light/variable winds will become south to southwest at 5-10 mph
tonight. South to southwest winds will increase to 10-15 mph
Thursday afternoon, and may occasionally gust up to 20-25 mph late
in the afternoon into Thursday night, especially in north/south
oriented valleys such as the Hudson Valley and also across higher
terrain.

&&

Hydrology...
scattered showers and thunderstorms are expected Thursday and
Friday. Most rainfall amounts should remain below an inch,
although locally higher amounts will be possible in thunderstorms.
Localized ponding of water in low lying/poor drainage and urban
areas will be possible late Thursday 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...iaa/snd
near term...NAS
short term...sand
long term...iaa
aviation...kl
fire weather...snd/kl
hydrology...sand

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