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000 
FXUS61 KALY 181748
AFDALY

AREA FORECAST DISCUSSION
National Weather Service Albany NY
148 PM EDT Fri Oct 18 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 PM THIS EVENING/...
As of 147 PM EDT...A large closed low continues to be located 
over Atlantic Canada, with moist, cyclonic flow dominating our 
region. An additional piece of energy rotating around this upper
level feature is moving across the area for this afternoon. 
Visible satellite imagery continue to show plenty of clouds in 
place, with just a few breaks occurring for valley areas. 
MRMS/KENX radar shows just some very light rain showers or 
sprinkles occurring across Schoharie County, the Mohawk Valley,
the Adirondacks and Lake George-Saratoga Region, but these are 
very light and not producing any measurable precipitation. This 
should continue for the next few hours, but will start to 
decrease by late afternoon or early evening, as the weak 
shortwave continues to rotate eastward into New England.

Although it will be mostly cloudy for most of the afternoon,
some breaks in the clouds will be developing in north-south 
valleys by the early evening. Clouds will tend to hold tough 
over the mountains with the continued northwest flow. Temps
continue to hold steady due to the chilly northwest flow and
plenty of cloud cover, with afternoon temps mainly in the 40s to
low 50s. In addition, it will feel even colder, as northwest
winds of 10 to 20 mph continue to blow through the rest of the
day.  Some gusts up to 30 mph are possible as well. 

&&

.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/...
Skies will clear tonight, even across the higher terrain, as
subsidence from high pressure both at the surface and aloft
moves in from the west. With the anticyclone building in, winds
speeds will decrease, especially during the pre-dawn hours.
Clear skies and diminishing winds will lead to radiational
cooling and frost formation. A Frost Advisory has been issued 
for the Hudson Valley from the Capital District southward and 
southern Litchfield CT. These are the only areas where the 
growing season continues. 

After cool/frosty start to the day, Saturday will feature
abundant sunshine and light winds with temperatures warming to
near normal level during the afternoon as high pressure and
ridging aloft moves overhead. It will be a good day for any
outdoor fall activities planned. Mostly clear and cool
conditions will persist through Saturday night, as high 
pressure shifts east into New England. 

Dry weather should prevail through Sunday as well, as a
potential tropical cyclone will track well south and east of our
region. Model guidance is indicating a weak upper level short
wave trough moving through the mean ridge during the day. This
could bring some added cloud cover compared to Saturday, but
should have little impact otherwise. Temperatures will be
similar to Saturday with continued light winds.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
The extended begins with fair weather and above normal
temperatures, but unsettled weather returns Tuesday into
Wednesday with a cold front and a wave of low pressure
potentially moving along it.

Sunday night into Monday...A post tropical system passes well
south and east of the region Sunday night based on the majority
of the medium range guidance, as weak high pressure builds in at
the sfc. Mid and upper level heights rise over the Northeast 
ahead of the next potent mid and upper level longwave trough. 
After a cool start Monday morning with lows in the mid 30s to 
lower 40s, max temps to start the week will be in the lower to 
mid 60s in the valleys, and mid 50s to around 60F over the 
higher terrain.

Monday night into Tuesday...A deepening and intensifying sfc 
low will be moving into the Upper Midwest and the western Great 
Lakes Region. A warm front associated with the wave may bring 
some isolated showers into the region Monday night. Slight 
chance PoPs were used here. The mid and upper level ridge axis 
will be moving down stream of the forecast area. A mild night is
expected with increasing clouds with lows mainly in the 40s. 
The mid and upper level trough begins to show a negative tilt in
some of the guidance late Tuesday, as the initial surge of 
moisture will be with the cold front. The low level convergence 
combined with Gulf moisture will bring a period of rain into the
forecast area, as likely PoPs were continued with highs in the 
50s to around 60F. Tuesday night into Wednesday...A period of 
unsettled weather continues with some rain into the evening with
the main question being if a wave develops along the front. The
00Z EC continues to indicate this possibility with a period of 
moderate to heavy rain with the H500 trough being negatively 
tilted. PWATs do rise above normal and the front may continues 
to provide a focus for rain most of the night. We kept likely 
PoPs in Tue night, and lowered to chance PoPs based on the 
slower CMC and EC runs, as the 00Z GFS continues to be the 
fastest. Lows in the mid 30s to mid 40s will be followed by 
seasonable temps on Wednesday with brisk winds.

Wednesday night into Thursday...The mid an upper level flow
becomes zonal with high pressure ridging in from the Mid
Atlantic States. Fair and dry weather is expected after a cool
start with lows in the 30s, then expect temps to moderate to
slightly above normal readings.

&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
High pressure will be gradually building in from the Ohio 
Valley through Saturday.

Clouds continue to linger in the wake of the powerful low
pressure system as of early this afternoon. In cyclonic flow, 
MVFR/VFR conditions are continuing at KGFL/KALB/KPSF with cigs 
in the 2-3 kft AGL range. KPOU has VFR stratocumulus in the 
3.5-5 kft AGL range. Expect these conditions to persist through 
early evening, with Cigs occasionally becoming VFR at KALB and 
KGFL.

Subsidence with the ridge building tonight should allow the 
skies to begin to clear between 23Z/FRI to 04Z/SAT, although
there is a possibility that the clouds could linger a bit
longer. VFR/MVFR Cigs will remain possible until the clouds
erode at KGFL, KALB and especially KPSF.

There is a chance of fog developing once skies become clear
before sunrise, especially at KGFL, where IFR/LIFR conditions
could briefly occur. There is also a slight chance that fog may
develop right around 11Z-12Z/Sat at KPOU. Chances are less for 
fog development at KPSF and KALB where a persistent breeze is 
expected.

The winds will be west to northwest at 8-14 kts with some gusts
20-25 kts this afternoon due to the sfc pressure gradient 
between the sfc high building in and the departing cyclone. The 
winds will diminish to less than 10 kts after 03Z/SAT...and 
become light to calm after midnight. West to northwest winds
should resume Saturday morning at 5-10 KT.

Outlook...

Saturday Night: No Operational Impact. NO SIG WX.
Sunday: Low Operational Impact. NO SIG WX.
Sunday Night: No Operational Impact. NO SIG WX.
Monday: No Operational Impact. NO SIG WX.
Monday Night: Low Operational Impact. Slight Chance of SHRA.
Tuesday: High Operational Impact. Likely SHRA...RA.

&&

.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 RH values back near 100
percent and winds decreasing below 5 mph in most spots.

Dry weather is expected over the weekend with no precipitation.
RH 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 from 3 AM to 9 AM EDT Saturday for CTZ013.
NY...Frost Advisory from 3 AM to 9 AM EDT Saturday for NYZ049-050-
     052-053-059-060-064-065.
MA...None.
VT...None.

&&

$$
SYNOPSIS...Frugis
NEAR TERM...Frugis
SHORT TERM...JPV

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