Scientific Forecaster Discussion
fxus61 kaly 241642
Area forecast discussion
National Weather Service Albany New York
1242 PM EDT Wed may 24 2017
a weak upper level disturbance will bring some very light rain or
sprinkles to locations south and east of the capital region and
Berkshires this morning, and a weak boundary will bring isolated
showers across the Adirondacks for this afternoon...but otherwise
mostly cloudy conditions and dry weather is expected for most of the
day. Low pressure approaching from the southwest will bring another
bout of cool and damp weather for Thursday into Friday, with
occasional rain. Another brief period of fair weather is expected
Saturday, before more showers return for Sunday.
Near term /until 6 PM this evening/...
as of 1230 PM EDT, high level cirrus continues to stream across
much of the area with some cumulus forming over the
Adirondacks. This is where some isolated to scattered showers
will be possible this afternoon. Otherwise, most of the area
should remain dry today. Temperatures appear to be on track to
top out in the mid 70s later this afternoon, with the exception
of the high terrain locations which should reach the upper 60s.
So have freshened up the hourly grids and sent updates to ndfd
and web servers.
as of 1019 am EDT...in the southwest flow aloft
the forecast area is sandwiched between a disturbance passing
well south of Long Island...and a weak stationary frontal
boundary near the St Lawrence River valley. Some light sprinkles
have been reported across the Mid-Hudson valley or just north
of the kpou out of the mid and high cloud decks due to the
midlevel fgen associated with the wave to the south. We kept a
slight chc of very light rain in until noon for the extreme
southeast Catskills/southern Dutchess co. And southern
Litchfield co. A stray hundredth is possible. The skies will
remain generally mostly cloudy. Further north and west of the
capital some intervals of sunshine continue, but we expect the
clouds to fill back in across the western Adirondacks this
afternoon. The best chance of partial sunshine is from the
capital region/Lake George area eastward into the Berkshires for
the afternoon with the disturbance to the south moving further
out to sea.
Ahead of the stationary front to the north...additional
shortwave energy translating north/northeast from the
north/central Appalachians is expected to move across the
western Adirondacks this afternoon. Forecast soundings and the
NAM/GFS plane view graphics suggest some very weak instability
developing across the Adirondacks for the afternoon, with the
possibility of sb convective available potential energy of 250 j/kg or less. We continued to
indicate an area of isolated showers this afternoon across
mainly the southwest Adirondacks, but removed it across the
southern greens. There maybe a rumble of thunder, but due to
limited instability we kept it as showers for now.
Expect high temperatures to be warmest to the north and east of
Albany, where some more sunshine is expected through the day,
with highs reaching the mid and isolated upper 70s for lower
elevations, and upper 60s to lower 70s for higher terrain. To
the south and east of the capital region, high/mid level clouds
into the afternoon may limit high temperatures a bit, with
mainly upper 60s to lower 70s.
Short term /6 PM this evening through 6 PM Thursday/...
tonight, expect generally dry conditions through at least
midnight, with a gradual increase in clouds once again from
south to north. Some light rain is expected to approach from the
south and west toward daybreak across the eastern Catskills and
Mid Hudson valley region, but may remain S and west of the capital
region through 8 am. Have indicated high chance to likely pops
for areas south of I-90, and only slight chance or less to the north
through 8 am EDT Monday. Lows should fall into the upper 40s to
Thursday, rain should slowly expand north/northeast across the
region during the morning, but may hold off across southern VT,
the upper Hudson Valley and southern Adirondacks until
afternoon. Expect periods of rain of varying intensity for the
afternoon hours. Some weak elevated instability could bring a
few rumbles of thunder for southern areas in the afternoon, but
have kept out any mention at this time due to uncertainty
regarding the degree of elevated instability.
The bigger issue for Thursday may be strong winds across
portions of the southern greens, Berkshires, and Taconics, as a
strong low level jet translates across the region with 40+ knots
winds expected at and above h925. With some relatively dry air
expected within the boundary layer between bands of rain, it is
possible that some gusts of 40+ mph may mix down in the
afternoon hours in these areas. Will highlight these areas in
the hwoaly, as there is some possibility that a Wind Advisory
may be needed. Elsewhere, although some gusty winds will be
possible across mainly higher elevations, the potential to reach
or exceed advisory levels appears less at this time.
Temperatures may reach the upper 50s to lower 60s before
steadier rain overspread the region, with temps likely falling
in the afternoon once more persistent rain arrives and stronger
wet bulb cooling processes commence. Many areas may actually
fall to between 50-55 by late afternoon, if not perhaps slightly
cooler across portions of the Berkshires and southern Vermont.
Long term /Thursday night through Tuesday/...
after the initial moisture surge, we will be watching a rather
potent pv-anomaly rounding the base of an increasingly negatively
tilted trough aloft across the southeast Continental U.S. That is forecast to
lift rather quickly northeast overnight. While models differ on
placement, a surface low should evolve across the middle Atlantic
region and track toward the vicinity of Boston, Massachusetts 12z Friday. So
while there may be a break in the precipitation Thursday evening,
showers and/or periods of rain should fill back in across the region
a trowal wraps back westward overnight. At this time, seems
locations along and east of the Hudson River are under the higher
probability for rainfall as we will place the higher pops for these
areas. Overnight lows mainly into the 50s.
Friday appears to be a rather cloudy and soggy day as the
combination of the coastal low and moist cyclonic flow aloft will
keep the threat for wet weather in the forecast. The trowal
translates further east which will take the higher threat of
rainfall across western New England through the day. Highs will
range from the lower half of the 60s for valley locations to 50s
Friday night, trends toward a more tranquil pattern as the
aforementioned coastal and upper trough become further removed
allowing for short wave ridging to build across the forecast area.
While this will end most of the precipitation, the combination of
moist profiles from previous wet period of weather along with
lighter winds should allow for the increased potential of patchy
fog. Overnight lows will range from the 40s across the terrain to
lower 50s for the immediate capital region southward along the
Hudson River valley.
For the upcoming Holiday weekend, latest trends in the global model
suite are favoring a more drier pattern as the short wave ridge
becomes a bit more pronounced Saturday through Sunday morning. So
under partial sunshine, highs should climb toward or exceed 70f for
many locations as Saturday night lows mainly into the 50s.
Later Sunday, models diverge with respect to timing of next short
wave approaching. Subtle hints of an mesoscale convective system that develops in the
vicinity of the Ohio Valley tracks east-northeast toward the northeast corridor
later Sunday afternoon into Sunday night. We will trend pops a
little higher but keep values below likely thresholds at this time.
Monday into Tuesday, another closed upper low develops across the
Great Lakes region with a series of waves transversing through the
cyclonic flow. This will keep the threat of showers and perhaps a
thunderstorm through Tuesday. Temperatures will average for highs
between 65-75f and overnight lows mainly into the 50s.
Aviation /18z Wednesday through Monday/...
generally VFR conditions are expected through at least 08z/Thu.
Some very light rain or sprinkles may affect kpou and kpsf
between roughly 11z-16z/Wed, as a weak low pressure system
passes off the mid Atlantic coast. Conditions should remain VFR
during this time, however.
Some lower clouds may develop and/or expand northward, and
reach kpou and kpsf toward 12z/Thu. Overall probability is low,
so will only suggest a scattered deck reaching these sites for now
In addition, some light rain may approach kpou toward 12z/Thu,
but vsby is expected to remain VFR through that time.
Light/variable to calm winds through daybreak should trend into
the southeast to south at 5-10 knots later Wednesday morning into
the afternoon. Winds should become light and variable again
Wednesday evening, except may remain southeast to south at kalb
through the night at 5-10 knots.
Thursday night: high operational impact. Likely rain showers...dz.
Friday: high operational impact. Likely rain showers.
Friday night: low operational impact. Slight chance of rain showers...fg.
Saturday: no operational impact. No sig weather.
Saturday night: no operational impact. No sig weather.
Sunday: moderate operational impact. Chance of rain showers...tsra.
weak high pressure will bring generally fair weather today, although
a passing upper level disturbance could bring some light rain to
southern areas this morning, and isolated showers across the
Adirondacks for this afternoon. Low pressure approaching from the
southwest will bring another bout of cool and damp weather for
Thursday into Friday, with occasional rain. Another brief period of
fair weather is expected Saturday, before more showers return for
Rainfall amounts of one half inch to one inch are expected from
Thursday through late Friday afternoon.
generally dry weather is expected today and tonight, except for
some very light rain across southern areas this morning, and
isolated showers/thunderstorms across the western Adirondacks
Widespread rainfall is expected across the area Thursday into
Friday as a slow moving low pressure system approaches and moves
across the region. Rainfall amounts of one half inch, to around
an inch are expected.
Fair weather is expected for Saturday, however unsettled weather
returns for the latter part of the Holiday weekend through at
least early next week with additional rainfall.
These periods of rain may result in some within bank rises 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.
the ASOS in Glens Falls at the Floyd Bennett Memorial Airport
still is not transmitting observations. It has been out of
service since severe thunderstorms impacted the area Thursday
evening, may 18th. Technicians continue to work on restoring