264
FXUS61 KALY 181957
AFDALY

AREA FORECAST DISCUSSION
National Weather Service Albany NY
357 PM EDT Wed Sep 18 2024

.SYNOPSIS...
Surface high pressure continues through tonight with increasing
clouds as a weather system moves along the Atlantic Coast. This
weather system could bring chances of rain showers into
Thursday. Friday could see some lingering showers in the Mid-
Hudson Valley and Litchfield Hills region, otherwise dry
conditions are in store into this weekend through early next
week with seasonable temperatures.

&&

.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
Zone of thick high clouds in much of eastern NY and western New
England but satellite picture trends show the high clouds
shifting north and some more scattered lower clouds just south
of the eastern Catskills and mid Hudson Valley holding nearly
stationary.

Upper ridging north and west of the developing coastal system
well south of Long Island may enhance some subsidence and allow
for the high clouds to thin through the evening and night with
some possible river and wetland fog again, and some scattered
low clouds across the region. Light to calm winds will help for
some radiational cooling where the high clouds thin and where
there is clearing.

Low level dew points have risen as boundary layer flow had
become more east to southeast. So, once temperatures approach
dew points later tonight, again, patchy fog with low
temperatures a little warmer than past nights. Lows in the mid
to upper 50s with around 50 to lower 50s northern areas.

&&

.SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
System offshore continues to organize and there are some
differences in sources of guidance/ensembles as to how far north
and west the rain shield gets. Intervals of clouds and sun
Thursday as any northern edge of any precipitation shield would
hold off until Friday, with the best chances on Friday in the
mid Hudson Valley, Litchfield Hills and Berkshires. A northern
stream upper impulse dropping out of far eastern Canada is
expected to push slightly cooler air from the north and east
into our region and that low level forcing could interact with
the coastal storm, supporting the scattered showers in our
region. An isolated shower cannot be ruled out from the
Schoharie Valley to Capital Region to southern Vermont.

So, with the intervals of clouds and sun Thursday, and more
clouds with more clouds south and east of the Capital Region,
temperatures will be a little cooler than recent days, but highs
Thursday will be in the mid 70s to lower 80s. On Friday, the
better chance of showers with the weak backdoor front and
northern precipitation shield from the coastal storm, highs in
the mid to upper 70s with lower 70s higher terrain.

Lingering clouds and isolated showers east of the Hudson River
Saturday with less cloud cover west of the Hudson River as the
coastal system begins to slowly exit and the weak backdoor
front washes out. Highs Saturday around 70 to mid 70s. Slowly
improving sky Saturday night, especially in western areas with
lows in the 50s.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
Flat upper ridging builds in from the west, as overall upper
heights fall with an approaching developing upper impulse
approaches from Canada and the Great Lakes, dry weather Sunday
through Tuesday with possible showers by later Tuesday through
Wednesday with the approach of a cold front.

There are lots of differences in sources of guidance as to the
strength of the upper energy, the timing and any colder air as
the system exits. Temperatures will at least be normal, with a
chance for a bit above normal if the upper ridging weakens the
upper energy and there is less cool air behind the system. But
for now, the best chances for showers look to be later Tuesday
and Wednesday but confidence is low.

Highs Sunday through Wednesday in the upper 60s to lower 70s
with cooler in higher elevations.

&&

.AVIATION /20Z WEDNESDAY THROUGH MONDAY/...
Through 18z/Thu...VFR conditions are expected for much of the
upcoming TAF period as a low pressure system to the south
spreads bkn-ovc high clouds across the TAF sites. The exception
would be for any patchy fog development tonight. The high cloud
deck may be thick enough to prevent fog formation at most sites.
KGFL may be most favored for fog as cloud thickness and
coverage will be lower compared to elsewhere and is more
climatologically favored. As a result, will introduce reduced
vsbys at just KGFL with this update and keep all other sites VFR
for now. Enough dry air in the low levels should prevent any
precipitation through 18z/Thu.

Light and variable wind at 5 kt or less will continue through
this afternoon before trending calm tonight. Wind will increase
to 5 to 10 kt out of the north to northeast Thursday morning.

Outlook...

Thursday Night: No Operational Impact. NO SIG WX.
Friday: Low Operational Impact. Isolated SHRA.
Friday Night: Low Operational Impact. Isolated SHRA.
Saturday: Low Operational Impact. NO SIG WX.
Saturday Night: Low Operational Impact. Isolated SHRA.
Sunday: No Operational Impact. NO SIG WX.
Sunday Night: No Operational Impact. NO SIG WX.
Monday: No Operational Impact. NO SIG WX.

&&

.ALY WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
MA...None.
VT...None.

&&

$$

SYNOPSIS...NAS
NEAR TERM...NAS
SHORT TERM...NAS
LONG TERM...NAS
AVIATION...Rathbun