Scientific Forecaster Discussion
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Area forecast discussion
National Weather Service Albany New York
205 am EDT sun Sep 15 2019
a cold front will continue to slowly move across the region,
with isolated to scattered showers ending overnight. High
pressure will build in briefly on Sunday with fair and dry
weather. Another front and an upper level disturbance will bring
light scattered showers Sunday night into Monday before dry
weather returns into the mid week with seasonable temperatures.
Near term /until 6 am this morning/...
as of 132 am EDT...cold front is in the process of moving
across eastern New York. It's somewhat difficult to pick its
exact location, as there is only a subtle temp/dewpoint
difference immediately behind the front, with the much drier and
cooler air still well upstream across Ontario and western New
York. Still, based off New York state mesonet observations and latest kenx
radar imagery, it looks like the front is now located across the
eastern Catskills, Mid Hudson valley, Taconics and into western
New England. The bulk of the clouds are now departing into New
England, but some lingering low stratus remains. Areas that have
cleared out are starting to see some radiational fog develop as
well, as the light winds and slow movement of the drier air
moving in is allowing fog to form.
Through the rest of the overnight, the threat for showers seems
to have ended, as radar shows activity has diminished and
mesoscale models seem to suggest any additional showers will be
occurring in a broken line from coastal New Jersey
northeastward towards eastern New England. The front will
continue to slowly drift southeast through the rest of the
night. Some patchy fog and low stratus should continue through
about sunrise, mainly for valley areas and locations close to
bodies of water.
Overnight lows look to fall into the 50s for most spots,
although a few upper 40s are possible across the western
Adirondacks, where skies have been cleared the longest.
Short term /6 am this morning through 6 PM Monday/...
tomorrow...a weak sfc high builds in over New York and New England
ahead of the next short-wave. Mostly sunny skies early in the
day will give way to an increase of clouds in the afternoon. A
few showers may graze the western Adirondacks before sunset.
Highs will be near seasonable normals in the lower to mid 70s in
the valleys with a few upper 70s sprinkled in over the Mid
Hudson valley and northwest CT, and mainly 60s over the higher terrain.
Sunday night...clouds continue to thicken and lower with the
short-wave in the northwest flow aloft. The moisture convergence
is not very strong, as some Great Lakes moisture is tapped, and
some weak thermal advection occurs north of the old front from
Saturday night. Slight to low chance pops were kept in the
forecast especially after midnight over the County Warning Area
based on the NAM/GFS-fv3/ECMWF/CMC and the ensembles. Lows will
be mainly in the mid to upper 50s with some upper 40s to lower
50s over the northern most zones.
Monday...unsettled to start the day, but improving weather by
the afternoon, as the short-wave moves south and east of the
region with the isolated-scattered showers ending by the late
morning/early PM. The mid and upper level trough amplifies over
the northeast and eastern Canada. High pressure builds in from
the Great Lakes region with clearing skies from northwest to
southeast. In the low to mid level cold advection, 850 hpa temps
fall to +6c to +10c with Max temps a shade below normal with 60s
to lower 70s over most of the forecast area with a few mid 70s
over the Mid Hudson valley and southern Litchfield co.
Monday night into Tuesday...fair, tranquil and cool weather with
high pressure in control. High pressure settles over southeast
Ontario and upstate New York Monday night into Tue morning with ideal
radiational cooling. Lows will be in the 40s with some spotty
upper 30s in the southern Adirondacks. The subsidence from the
sfc anticyclone and ridge aloft with yield mostly sunny/sunny
conditions with highs near or slightly below normal for Tue.
Long term /Monday night through Saturday/...
a prolonged stretch of dry weather is on tap.
A check of the gefs precipitation plumes for Albany shows nearly all
members flatlining for the extended. Looking at some of the gef
ensemble output, precipitable waters remain in the normal range through Saturday.
925mb/850mb temperature anomalies are near normal for Wednesday and
Thursday before rising to 1 to 2 Standard deviations above normal
for Friday and Saturday. 500mb height anomalies start near normal
before rising to 1 to 2 Standard deviations above normal for Friday
As for what this means for US...high pressure at the surface and a
building ridge aloft will dominate our area for most of the long
term. This will result in mostly clear skies and seasonable
temperatures for Wednesday and Thursday with an increase in
temperatures for Friday and Saturday. Temperatures start out in the
low 70s valleys, 60s higher terrain, reaching near 80 valleys and
60s/70s higher terrain on Saturday. Other than a slight chance of
some rain for Saturday, the extended is dry.
Tropical Storm Humberto forecast to become Hurricane Humberto is not
expected to impact our weather. See the National Hurricane Center
for the official forecast for Humberto.
Aviation /06z Sunday through Thursday/...
a very weak cold front continues to track eastward through the
region with only weak mid-level dry air advection noted on the
latest satellite imagery. The mid-level cloud deck and isolated
showers associated with the weak boundary continues to move east
of gfl and alb and is tracking towards psf. Given that sfc dew
points remain rather high near 60f and some showers reached pou
earlier today, fog and IFR visibility have developed along with
low stratus/IFR ceilings once the mid-level clouds cleared and
we expect IFR/MVFR category through 13z this morning.
Psf and gfl continue to vary between VFR and IFR ceilings and
visibility due to variable wind speeds. As winds lighten,
ceilings/visibilities reduce to IFR conditions but when winds
increase, VFR conditions return. We illustrate this variation
with a tempo group. Alb could see patchy fog develop 09z-12z but
with drier air finally working into the area and dew points
lowering, VFR conditions should prevail.
All sites will see VFR conditions return by around 13z, with
just some high level clouds increasing during the afternoon.
Winds will become west-northwest late tonight and will increase
to around 5-10 kt on Sunday.
Sunday night: moderate operational impact. Chance of rain showers.
Monday: moderate operational impact. Chance of rain showers.
Monday night to thursday: no operational impact. No sig weather.
a cold front will move across the region into this evening with
isolated to scattered showers ending. High pressure will build
in briefly on Sunday with fair and dry weather. Another front
and an upper level disturbance will bring light scattered
showers Sunday night into Monday.
The relative humidity values will increase to 100 percent Sunday morning, and
lower to 45 to 65 percent in the afternoon. Another excellent
recovery is expected in the relative humidity trends with maximum values of 85
to 100 percent Monday morning.
The winds will shift to the west or northwest at 5 to 10 mph
tonight, and continue through the day on Sunday. The winds will
be light and variable direction at 5 mph or less Sunday night.
no significant hydrological problems are expected on the main
Stem rivers the next week or so.
A weak front late this afternoon into tonight will bring light
precipitation amounts, and another disturbance will bring a few
hundredths to a couple tenths of an inch of rainfall Sunday
into Monday with mainly dry weather thereafter.
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.