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fxus61 kaly 190556 
afdaly

Area forecast discussion
National Weather Service Albany New York
156 am EDT Sat Oct 19 2019

Synopsis...
as high pressure builds into the region, winds will decrease and
clouds will finally break up tonight, with some areas of frost
forming late. High pressure will allow for dry conditions this
weekend, with mainly clear skies and temperatures running just a
little below normal. Dry and mild conditions are expected on
Monday before a frontal boundary returns some rain to the region
for Tuesday into Tuesday night.

&&

Near term /until 6 am this morning/...

As of 1:30am, clouds continue to slowly erode away as northwest
flow gradually shifts westerly, allowing US to lose the flow off
the lakes. Goes16 nighttime fog channel especially show areas
where we have the frost advisory (albany south along the Hudson
River into the Mid-Hudson valley in addition to southern
Litchfield county) going into effect at 3am becoming clear. With
dew points in this areas still ranging 34-36f, we're gaining
confidence that these areas will radiate over the coming hours
allowing frost to form as we head towards sunrise. Just minor
adjustments to sky cover and temperatures for this update.
Previous afd has a few more details and is below...

At the surface, a large area of high pressure will be
approaching from Ontario and the upper Ohio River valley. Drier
air working its way into the region should allow skies to clear,
although it may take the longest to clear across the
Adirondacks and southern Vermont. Winds will diminish as well
and the combination of clearing skies and decreasing wind should
allow temps to fall through the 40s and into the 30s. Some
areas of frost are possible for the capital region, Mid Hudson
valley and southern Litchfield County, where the growing season
is technically still ongoing. A frost advisory is in effect for
these areas for late tonight. Although a heavy frost isn't
expected, the clearing should occur quick enough for frost to
form late tonight, which may end the season for any sensitive
vegetation. Can't rule out a few patches of fog as well in The
Glens falls area as well, although this will ultimately depend
on how quickly clearing occurs.

Overnight lows will range from the upper 20s in the Adirondacks
to the low to mid 30s elsewhere.

&&

Short term /6 am this morning through Sunday night/...
dry and pleasant weather is expected through the entire short
term period.

Upper level ridging will build over the area for Saturday, with
the ridge axis shifting eastward across New England by Sunday.
Surface high pressure will be situated over the area for
Saturday, and shift offshore for Sunday.

As a result, skies look to be completely clear for Saturday into
Saturday night. Some clouds are possible for Sunday, but skies
will still generally be partly to mostly clear. The bulk of the
latest model and ensemble guidance suggests that the remains of
tc Nestor should stay south/east of the region, so aside from
some additional cloudiness, no impact is expected across our
area and any rainfall should remain over the southeast and mid
Atlantic states.

Temps should reach the upper 40s to upper 50s for Saturday with
abundant sunshine in place. Good radiational cooling will drop
temps into the 30s for Saturday night and some frost is possible
once again. On Sunday, it should be a little milder with
southerly return flow, with expected highs in valley areas
reaching the mid to upper 50s. Lows on Sunday night will fall
into the mid 30s to mid 40s.

&&

Long term /Monday through Friday/...
Ridge of high pressure to start the long term period is
expected along the Atlantic Seaboard. Should be rather nice mid
October day with above seasonable temperatures as highs range
from the low-mid 60s for valley locations to upper 50s across
the higher terrain.

Meanwhile, upstream will be a developing and deepening storm
across the Central Plains states. Moisture transport along and
ahead of the frontal boundary will slowly advect north-
northeastward overnight Monday into Tuesday morning. As global
models appear to have slowed down the onset, we too will slow
down the pops/wx and have just our western zones with a slight
chance. Clouds increase as overnight lows will generally be in
the 40s.

Tuesday looks to be a rather damp day with periods of rainfall
as frontal system and moisture transport will be maximized
across the northeast corridor. Unlike our last storm, the
cyclogensis along the front appears to be less of a signal than
previous runs. Under clouds and periods of rainfall, high
temperatures not likely to get out of the 50s.

Tuesday night into Wednesday, global models differ a bit with
respect to just how fast the frontal zone passes through. A
couple waves along the frontal zone embedded within the upper
trough may slow down its forward progress a bit so we will keep
chance pops/wx in the forecast at this time. MOS temperatures
are not too much different as we will follow with a blended
approach with lows generally in the 40s and highs into the 50s.

Wednesday night into Thursday, the European model (ecmwf) and ggem are in closer
agreement than the GFS with the extended influence of the
southeast conus ridge into the mid-Atlantic and northeast. This
would reduce the chance for wet weather across the region along
with slightly milder weather. However, beyond the long term, a
pattern shift appears to be in the making with a colder shot of
air arriving...more on those details in future discussions.

&&

Aviation /06z Saturday through Wednesday/...
ridging builds in at the surface and aloft through the taf period.
Cloud will continue to gradually erode overnight with deeper
subsidence expected through the early morning hours. There could
be some IFR visibilities in fog at kgfl between 09-12z with the
clear skies and calm winds. Any fog will burn off after sunrise
then VFR conditions expected with clear skies through the day
with some cirrus streaming for the evening.

Light westerly flow to calm winds at tafs sites overnight with a
light west-northwest wind Saturday at 6 knots or less than less.

Outlook...

Saturday through Monday night: no operational impact. No sig weather.
Tuesday through Tuesday night: high operational impact. Likely
rain.
Wednesday: moderate operational impact. Chance of rain showers.

&&

Fire weather...
our entire region saw a soaking rainfall on Wednesday into
Thursday. Clouds will finally break up for tonight as high
pressure builds into the area from the west. Some dew or frost
formation is expected tonight with relative humidity values back near 100
percent and winds decreasing below 5 mph in most spots.

Dry weather is expected over the weekend with no precipitation.
Relative humidity values will fall to 50 to 60 percent each afternoon. West
winds will be around 5 mph on Saturday and southerly winds will
be around 5 mph for Sunday.

&&

Hydrology...
after the recent heavy rainfall, rivers and streams saw sharp
rises, but have finally crested on Friday. River and streams
levels will be falling tonight into the weekend, as no
additional precipitation is expected. River levels will continue
to drop or be steady early next week, with continued dry
weather on Monday. The next chance of rain will be with a
frontal boundary for Tuesday into Tuesday night, although exact
amounts are still uncertain at this time.

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...frost advisory until 9 am EDT this morning for ctz013.
New York...frost advisory until 9 am EDT this morning for nyz049-050-052-
053-059-060-064-065.
Massachusetts...none.
Vermont...none.

&&

$$
Synopsis...frugis
near term...NAS/speciale

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