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Area forecast discussion 
National Weather Service Albany New York
721 PM EDT Wednesday Sep 28 2016

Synopsis...
high pressure will ridge in from eastern Quebec through tonight
with mainly dry and seasonable temperatures...except for some
isolated showers or sprinkles from the eastern Catskills through
Mid Hudson valley into western New England. A slow moving low
pressure system near the Ohio Valley will gradually move towards
New York and New England with an increase of scattered showers
Thursday into Friday with cooler temperatures.

&&

Near term /until 6 am Thursday morning/...
as of 715 PM EDT...skies across the region were partly to mostly
cloudy with more in the way of clouds to the south and east and
less in the way of clouds to the north and east. Some showers
across northeast Pennsylvania and southeast New York continue to
track northeast toward the southeast Catskills, but they continue
to erode as they move into slightly drier air. Temperatures across
the region early this evening were generally in the mid 50s to
early 60s.

High pressure in Canada will build south and west into our
northern areas while east and southeast low level flow off the
ocean east and south of New England brings low level moisture and
cloud cover into southern areas. The circulation around the
developing upper low in the Great Lakes is drawing some deeper
moisture from the mid Atlantic area toward the eastern Catskills.

Shallow moisture in New England should slowly deepen as well but
without much forcing, just some isolated showers, sprinkles or
drizzle can be expected tonight perhaps due to some upslope
processes. In the eastern Catskills and Mid Hudson valley, the
leading edge of some of the rain should begin to affect those
areas between midnight and daybreak.

Temperatures tonight will be very dependent on what areas see some
clearing through much of this evening and what areas stay cloudy
most of the night. Western New England through the eastern
Catskills should see the most cloud cover, but some drying at the
surface is possible into southern Vermont and the northern Berkshires
and points north. So, low temperatures are tricky. Lows in the
southern Adirondacks and Lake George region, southern Vermont and parts
of the Berkshires will see lows in the 40s to near 50. Lows
elsewhere in the 50s.

&&

Short term /6 am Thursday morning through Saturday/...
considerable disagreement in sources of guidance as to the timing
and areal extent of clouds and rainfall as the upper low drifts
around the Ohio Valley and southern Appalachians through Saturday.
Regardless of the track of the upper low, there is considerable
moisture in the southeastern U.S. Through the mid Atlantic area
extending offshore into the Atlantic Ocean that should get drawn
north and northwest into our region, especially toward Friday and
Friday night.

After some areas of rain in the eastern Catskills through Mid
Hudson valley into northwest CT Thursday morning, low level ridging
continuing to build south out of Canada is expected to delay the
onset of the next round of better coverage of rain. There may be
limited cloud cover in northern areas as the low level ridging
influences our weather later Thursday and Thursday night and where
the clearing versus cloud cover sets up is in question. In
general, highs Thursday should be a little warmer to the north and
cooler to the south due to the periods of sun versus cloud cover.
So, highs Thursday in the mid to upper 60s many areas.

So far, the best consensus for best coverage of rain looks to be
Friday and Friday night, when a small upper impulse with some
slightly better upper dynamics and low level jet forcing and
moisture advection/convergence around the outer periphery of the
upper low circulation through our region. The likely coverage
looks to be in central and southern areas with chances in northern
areas, closer to the low level ridging. Better coverage of clouds
and rain should result in cooler temperatures Friday, around 60 to
lower 60s in central and southern areas and mid 60s to the north.

Chances for rain continue Saturday as the upper low drifts east
with highs in the upper 50s to lower 60s. Timing and coverage of
rain likely to change as upper low evolution can be tracked
through the rest of the week and weekend.

&&

Long term /Saturday night through Wednesday/...
the long term forecast starts out unsettled and ends dry. The
biggest question for the Saturday night through Monday time frame
will be what happens with the upper closed low in the upper Great
Lakes region and it's impact on our region.

For now will forecast unsettled weather from Saturday night through
Monday with a chance of showers during the entire period. The
greatest chances are expected over the later half of the weekend and
then have chances lowering by Monday. The surface low is expected to
track from the upper Great Lakes region Sunday morning lifting an
occluded front through the region. The low will then pass across
southern Ontario and southern Quebec on Monday with several troughs
of low pressure close by. Lows Saturday night are expected to be in
the upper 40s to mid 50s with highs on Sunday in the upper 50s to
upper 60s. Lows Sunday night are expected to be in the upper 40s to
mid 50s with highs on Monday in the upper 50s to upper 60s.

Dry weather is then expected Monday night through Wednesday as a
large ridge of high pressure builds across the region in the wake
of the low pressure system. Lows Monday night are expected to be
in the mid 40s to mid 50s with highs on Tuesday in the upper 50s
to upper 60s. Lows Tuesday night are expected to be in the 40s
with highs on Wednesday in the upper 50s to mid 60s.

&&

Aviation /23z Wednesday through Monday/...
a persistent easterly flow will continue through the 24 hour taf
period ending 00z Thursday, with high pressure remaining anchored
over Quebec and a stalled low pressure system near the in/Kentucky
border. Plenty of clouds will affect the terminals through
tonight, with generally MVFR levels at kpou and kpsf tonight. Cigs
expected to remain VFR at kalb/kgfl with easterly flow resulting
in some downsloping.

Slightly drier air seeping south and west should allow for a
decrease in lower clouds at kgfl, kalb and kpsf between late
morning and afternoon on Thursday, with VFR conditions prevailing.
At kpou, low clouds will persist, although cigs should at least
rise into the VFR range by afternoon.

Winds will be northeast-east around 7-12 kt through the next 24
hours, with some gusts of 15-20 knots possible, particularly at kpsf.

Low level wind shear will be possible at kpou overnight as sfc
winds remain from the NE at 5-10 kt, while winds around 2000 feet
above ground level increase from the east at 30-35 knots.

Outlook...

Thursday through monday: moderate operational impact. Chance of rain showers.

&&

Fire weather...
high pressure will ridge in from eastern Quebec through tonight
with mainly dry and seasonable temperatures...except for some
isolated showers or sprinkles from the eastern Catskills through
Mid Hudson valley into western New England. A slow moving low
pressure system near the Ohio Valley will gradually move towards
New York and New England with an increase of scattered showers
Thursday into Friday with cooler temperatures.

The relative humidity values will recover to 75 to 100 percent tonight and
Thursday night. The relative humidity values will remain elevated in the 55 to 75
percent range Thursday afternoon and 60 to 80 percent Friday, when
rain will be likely over much of the region.

The winds will be east to northeast at 5 to 15 mph tonight
through Friday.

&&

Hydrology...
no widespread Hydro issues are expected the next 5 days ending on
Sunday.

Isolated to scattered showers may return tonight into the eastern
Catskills and Mid Hudson valley tonight and Thursday morning. A
more widespread rain is expected Friday through Saturday as an
upper low approaches from the Great Lakes and Ohio Valley.

The amount of rainfall is uncertain during the stretch, but
totals of a tenth to three quarters of an inch will be possible
in some locations depending on the track of the cutoff. At this
time, the best potential for rainfall will along and south of
Interstate 90 into the weekend. Locations further north and east
may only have lights amounts of rainfall...mainly under a quarter
of an inch.

The U.S. Drought monitor released on September 22nd shows drought
conditions have changed very little across the region. The next
issuance will be on September 29th. For details visit:
www.Drought.Gov

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...11/NAS
short term...NAS
long term...11
aviation...kl/jpv
fire weather...NAS
hydrology...NAS

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