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Area forecast discussion 
National Weather Service Albany New York
658 am EDT Thursday Aug 21 2014

Synopsis...
a slow moving weak low pressure system over the Great Lakes region
will impact the forecast area with showers and possibly a stray
thunderstorm as it drifts eastward overnight into Thursday night.
The low will track off the coast Friday. Moisture and a few stray
showers will linger Friday as cooler air filters in. This weekend...
high pressure will build over the eastern United States at all
levels of the atmosphere...with increasing sunshine...and warming
temperatures.

&&

Near term /through tonight/...
as of 630 am...a widespread area of showers was moving through the
northeast part of the forecast area...generally from the eastern
Mohawk Valley and southeast Adirondacks...eastward across the Lake
George Saratoga region...southern Vermont and northern Berkshire
County. Have increased probability of precipitation to categorical and likely across this
region for a couple of hours this morning until this area of showers
moves further east. Elsewhere generally chance probability of precipitation are forecast for
early this morning. Later this morning probability of precipitation are forecast to decrease
for a time...but by later today likely to categorical probability of precipitation are
forecast for most of the area once again...as additional middle/upper
level forcing begins impact the region...and chance probability of precipitation are
forecast across southeast areas.

It will be cloudy today with highs in the upper 60s and 70s.

&&

Short term /Friday through Saturday/...
the system will move off the coast tonight and early Friday...with
drier air working southwestward into the region from a sprawling
high pressure system over the Canadian Maritimes. Probability of precipitation are slowly
forecast to decrease tonight and Friday...with mainly just slight
chance probability of precipitation across the region by Friday afternoon. As the drier air
continues to push into the region and high pressure at all levels of
the atmosphere begins to build into the region...clouds will slowly
decrease late Friday through Friday night...with partly sunny skies
on Saturday.

Lows tonight will be in the middle 50s to lower 60s. Highs Friday middle
60s to lower 70s. Lows Friday night in the 50s. Highs Saturday in
the 70s.

&&

Long term /Saturday night through Wednesday/...
a nice stretch of weather is expected in the long term from the
weekend into the middle of next week with temperatures rising to slightly
above normal levels as we enter the last week of August.

Wpc guidance/ECMWF/ensembles/GFS are in pretty good agreement high
pressure will build in over New York and New England from southern Quebec and
northern New England Sat night...and be centered over the northeast
Sunday to Tuesday...as a middle and upper level ridge builds in from
the MS River Valley and plains. An upper level trough sets up down
stream over the Canadian Maritimes...and large-scale synoptic
subsidence will influence the weather over the long term stretch.

A weak cold frontal boundary with limited low-level moisture to work
with may move across the region Wednesday afternoon into Thursday.
Only a slight chance of showers was added to the gridded forecasts Wednesday
PM into Wednesday night northwest of the capital region.

Temperatures will start out cooler than normal for the close of the weekend
with 50s for lows...and highs in the lower to m70s in the
valleys...and m60s to l70s over the hills and mountains

Monday into Tuesday...h850 temperature moderate to +13c to +14c with decent
mixing...as surface high pressure drifts slightly south and west of
upstate New York and New England. Expect highs to reach the u70s to l80s
in the valley areas...and lower to m70s over the mountains lows will be
in the 50s to l60s. Wednesday looks like the warmest afternoon with
m70s to l80s for highs...and humidity levels creeping up with surface
dewpoints in the m50s to l60s.

&&

Aviation /12z Thursday through Monday/...
low pressure and its associated frontal boundary will impact the
eastern New York and western New England taf sites the next 24 hours with
periods of showers and perhaps some isolated thunderstorms.

A mixture of VFR/MVFR conditions continue late this morning at
kalb/kgfl/kpou/kpsf. The MVFR conditions are mainly from at kgfl
as bands of showers continue to persist ahead of the surface low and
frontal boundary. The closed upper level low over the central and
eastern Great Lakes region will keep the showers going much of the
morning especially from kalb north and east. Other showers will move
into the area between 21z and 00z/Friday lowering ceilings/visibilities to MVFR
levels again after a brief period of VFR conditions. Widespread MVFR
conditions are expected tonight with some IFR conditions in terms
of ceilings/visibilities at kpsf and possibly kgfl.

Some isolated thunderstorms are possible...but the probs are still
below 50 percent...so we will let later taf issuances address the
thunderstorm possibilities. The threat period looks like 20z to 04z/Fri.

The winds will light and variable this morning...and then increase
from the southeast to south at 5-8 kts. Expect light to calm winds
tonight again.

Outlook...

Friday: moderate operational impact. Chance of rain showers.
Friday night-monday: no operational impact. No sig weather.

&&

Fire weather...
scattered to numerous showers will persist through tonight. It will
remain mostly cloudy and damp for Friday with a few lingering
showers possible.

Relative humidity values will be elevated the next couple of days...generally over
60 percent...sometimes close to 100 percent...due to the wet weather
and cloudy conditions.

The wind will variable to southeasterly at 5-10 miles per hour today through
Friday.

&&

Hydrology...
no Hydro problems are expected on the main Stem rivers at this time.

A slow moving weak low pressure system over the Great Lakes region
will impact the forecast area with showers and possibly a stray
thunderstorm as it drifts eastward overnight into Thursday night.
The low will track off the coast Friday.

As of 400 am...radar indicates that localized amounts of up to three
inches of rain had fallen since Wednesday from the Mohawk Valley
into the Saratoga region. Generally a third of an inch to one and a
half inches of rain had fallen across the northwest third of the
forecast area...with much lower amounts elsewhere.

This system will continue to produce areas of showers through
tonight...with additional rainfall amounts of a half to one inch in
many areas...but localized amounts of another two to three inches
are possible.

Due to low river levels and fairly dry soil conditions before the
rain began...the impact on area streams and rivers will generally be
minor and no river flooding is expected. Be.

However...any shower or thunderstorm could produce localized heavy
rainfall amounts...which could result in significant ponding of
water on roadways and minor flooding in areas of poor drainage.

There could be some additional showers on Friday but these should be
light.

Dry weather returns by the weekend and for much of next week.

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...Snyder
near term...hwjiv/lfm/Snyder
short term...hwjiv
long term...lfm
aviation...wasula
fire weather...hwjiv
hydrology...hwjiv

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