Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Albany New York
655 am EDT Wednesday Aug 20 2014
a slow moving and weak low pressure system over the Great Lakes will
begin to impact our region today with increasing clouds and the
chance for showers. As this system slowly moves southeast...it will
keep a chance of showers and possibly a thunderstorms over the
region through Thursday night.
Near term /until 6 PM this evening/...
as the weak system over the Great Lakes slides slowly southeast...
clouds will increase today...with the chance of showers slowly
increasing late this morning and this afternoon. Showers will be
most numerous west of the Hudson Valley...with little if any
rainfall occurring over the western New England zones.
Highs today will be in the middle 70s to lower 80s...and it will become
increasingly humid as dewpoints increase into the low or middle 60s.
Short term /6 PM this evening through Friday night/...
the feature moving out of the Great Lakes will continue to affect
the region through at least Thursday night as it slowly slides off
the East Coast by Thursday night and Friday. On Friday...conditions
will begin to dry out as drier air tries to filter into the region
from northern New England...which will be the result of the flow
around a large high pressure system over the Canadian Maritimes.
From tonight through early Thursday night...mainly likely probability of precipitation are
forecast from the Hudson Valley westward...and chance probability of precipitation further
east. As the system slides off the East Coast...probability of precipitation are forecast to
decrease Thursday night...lowering to only 20 percent on Friday.
Lows tonight will be considerably warmer than the past few nights
with lows in the upper 50s to middle 60s. Highs Thursday will be in the
70s. Lows Thursday night in the middle 50s to lower 60s. Highs Friday
in the upper 60s to middle 70s.
Long term /Saturday through Tuesday/...
a tranquil extended forecast is anticipated for eastern New York and western New
England with high pressure building in from eastern Quebec...New
Brunswick...and northern New England early in the weekend...and lasting
into the early to middle portion of next week with seasonable temperatures
and fair weather.
Friday night into Saturday...a Rex type block sets up over eastern
Canada and the northeast with a closed h500 anticyclone over north-central
Quebec...and downstream of James Bay. A weak middle level trough sets
up over the middle Atlantic region and just southeast of New England.
The weak upper level trough and a frontal boundary over the Ohio
Valley and Upper Middle Atlantic region may focus some isolated showers
near the Catskills Friday evening...but most of the area will stay
dry. The blocking ridge strengthens on Saturday with the surface
anticyclone near the Gulf of St Lawrence and New Brunswick. H850
temperatures are expected to be in the +10c to +12c range with the onshore
flow. Lows will be mainly in the 50s with highs in the lower to middle
70s in the valleys...and u60s to l70s over the hills and mountains with
the onshore flow...some stratus is possible in the morning before
burning off before noontime.
Saturday night to Tuesday...high pressure continues to ridge in
from New Brunswick and northern New England. A broad closed upper
level low forms south of Nova Scotia. Our forecast area will be
sandwiched between the downstream cutoff and a broader high
amplitude h500 anticyclone centered over the plains. The h500 ridge
actually builds in from the southwest from the eastern Great Lakes
region and southeast Canada. Dry weather is expected based on the latest
European model (ecmwf)/GFS/wpc/ensemble guidance...as the upstream ridge looks to
dominate with seasonable temperatures expected with m60s to l70s for highs
over the higher terrain...and middle to u70s and perhaps some l80s over
the valleys by early next week /Tuesday/. Lows will be in the 50s
with some spotty u40s over the high peaks. Humidity levels will
continue to be fairly comfortable with surface dewpoints generally in the
50s to l60s. An onshore flow of maritime air will impact the region
with the surface high situated to the north and east....and some morning
stratus is possible each day. A weak disturbance may kick off a few
sprinkles or isolated showers over the southern dacks by early next
week...but overall fair and dry weather looks to dominate into the
Aviation /12z Wednesday through Sunday/...
high pressure has moved offshore...and a weak warm front is
approaching the region this morning. Another frontal boundary with
a surface wave over the Great Lakes region will slowly approach from
the west tonight into Thursday.
VFR conditions will prevail this morning with some MVFR ceilings
possible at kpou prior to noontime. Scattered-broken cumulus 3.5-5 kft above ground level
and middle and high clouds will be around in the afternoon. The best
chance of showers with a middle level disturbance ahead of the
occluded front will be after 23z. Vcsh groups were placed in the
forecast at all the taf sites between 23z to 02z/Thu. The better chance
of showers with MVFR/VFR ceilings visibilities will be shortly before or just
The winds will be light to calm this morning...and then increase
from the southeast to south at 4-8 kts. They will become light and
variable in direction tonight.
Thursday night: moderate operational impact. Chance of rain showers.
Friday: moderate operational impact. Slight chance of rain showers.
Friday night-Sun: no operational impact. No sig weather.
the weather will turn unsettled for the middle of the week as a slow
moving and weak low pressure system impacts the region. The best
chances for showers will be to the west of the Hudson River
valley...especially across the western Adirondacks...and western and
central Mohawk Valley Wednesday afternoon through Thursday night.
Minimum relative humidity values this afternoon will be between 45 and 60 percent
as dewpoints rise into the 60s in most areas. Surface winds will be
from the south or southeast at 5 to 10 miles per hour with some gusts of around
15 miles per hour. Relative humidity values will increase to near 100 percent tonight with
light southerly winds.
no Hydro problems are expected on the main Stem rivers at this time.
The weather will turn unsettled for the middle of the week as a
slow moving and weak low pressure system impacts the region. The
highest quantitative precipitation forecast amounts will occur to the west of the Hudson River
valley...especially across the western Adirondacks...and western and
central Mohawk Valley including the Catskills. Up to an inch of
rainfall is possible Wednesday afternoon through Thursday night. Due
to low river levels and fairly dry soil conditions...there will be
little if any impact on area streams and rivers.
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.