470
FXUS61 KALY 201745
AFDALY

AREA FORECAST DISCUSSION
National Weather Service Albany NY
145 PM EDT Fri Sep 20 2024

.SYNOPSIS...
Dry weather for most of the region through this weekend and
through Tuesday, with just an isolated shower possible in
western New England Saturday. Chances of showers increase
Tuesday night into Wednesday with unsettled weather conditions
for mid week. Temperatures become seasonable today and continues
for next week, with a few locations seeing cooler than normal
temperatures.

&&

.NEAR TERM /THROUGH TONIGHT/...
Clouds in western New England within the very northwestern edge
of the coastal low circulation. The clouds on satellite imagery
are very slowly exiting east, and may take much of the rest of
the morning and into the afternoon before more widespread
sunshine is seen. Sunny elsewhere. Based on current temperature
trends, forecasted high temperatures are in the ball park. Just
minor adjustments to temperatures and sky cover through this
afternoon.

PREVIOUS DISCUSSION:
For tonight, skies should be clearing to allow for fog to
develop overnight. Low temperatures cool into the 50s.

&&

.SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/...
The surface low pressure system off the Atlantic coast of MA/RI
will help contribute to keep eastern NY and western New England
dry as we are positioned in-between two low pressure systems,
one to our west and one to our east. We should remain dry that`s
favored by latest high resolution forecast model guidance over
us. A cold front from the north brings cooler, seasonable
temperatures for this weekend. While skies Saturday and Sunday
will be a mix of sun and clouds, dry conditions continue. Winds
during the morning hours remain light and variable, and with
radiational cooling, valley fog could develop each morning this
weekend. Seasonable temperatures are in store for this weekend.
High temperatures Saturday are forecasted to be in the upper 60s
to mid 70s. Low temperatures for Sunday morning are forecasted
in the upper 40s to low 50s. We could see high temperatures on
Sunday in the upper 60s to low 70s.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
Our approximately 2 week stretch of dry and benign weather comes to
end during the upcoming long term as broad troughing develops across
the Northeast with potential for even a cut-off low to form towards
the end of next week. As a result of this pattern shift, multiple
days will feature chances for rainfall by the middle to end of next
week. With the month-to-date September precipitation for much of
eastern NY and western New England only around or under 0.50", the
expected wetter pattern will bring beneficial rainfall as soils have
become quite dry. Temperatures will also trend relatively cooler but
will be quite seasonable for late September standards in response to
upcoming troughing. More details below.

We start off the period Monday into Tuesday with broad ridging aloft
centered over the TN/Ohio Valley extending into the Northeast with a
strong sfc high centered over eastern Quebec. This will maintain dry
and pleasant yet relatively cooler conditions Monday into most of
Tuesday. However, Tuesday into Wednesday, we note the start of our
pattern shift as broad troughing from the Upper Plains amplifies and
slides eastward, breaking down the downstream ridge. While there are
differences on the exact timing and amplitude of the incoming
trough, ensemble clusters from DESI show strong agreement for
troughing to ensue across the eastern CONUS which increasing
confidence for multiple chances for rainfall Wednesday through the
end of the work week. Meanwhile, ensemble guidance also suggests
that strong ridging becomes established over the West CONUS with an
omega block pattern potentially developing. Such a pattern upstream
may also support troughing over the Eastern CONUS transitioning into
a cut-off low towards the end of the work week as northern and
southern stream energy within our split flow potentially phase. We
will continue to monitor how the pattern evolves but the main
takeaway is that we can expect our sensible weather to become
wetter/unsettled, seasonably cool, and cloudier starting Tuesday
night into Wednesday and lasting through the end of the work week.
We thus have widespread chance POPs in place through this period.
Not enough confidence on exact shower coverage, timing, or duration
to include likely POPs at this time. Temperatures should rise into
the mid-upper 60s to low 70s each day with overnight lows dropping
into the low to mid 50s.

&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
Through 18z Saturday...VFR conditions prevail across all
terminals this afternoon with clouds streaming into the region
on the outskirts of a coastal system located south and east of
the Long Island Coast. KPSF has seen the cloudiest conditions
thus far today, being the closest to the influence of the nearby
system and as such has experienced MVFR ceilings throughout the
course of the morning. While visible satellite and latest obs
show some improvement, included a TEMPO for MVFR ceiling heights
over the next couple of hours until consistent improvement is
noted as is suggested by latest forecast soundings.

Throughout the overnight period tonight, cloud coverage looks to
be relatively variable. The fair-weather cumulus about the
region will dissipate, but with the coastal storm remaining
within reach, some additional bands of clouds will stream into
the region. Latest guidance points towards higher cloud bases
than previous runs, but largely VFR conditions should prevail.
Anticipated breaks in cloud coverage could aid in the
radiational cooling necessary to generate some patchy fog/mist
especially at the notorious KGFL terminal. Included a TEMPO to
reflect MVFR visibility for now, but this could be amended to
IFR in future updates should confidence increase. KPSF could
develop an MVFR ceiling again tomorrow morning, so added a TEMPO
for this as well as confidence is not high in those heights
being maintained much past the early morning hours.

Throughout the 18z cycle, winds will remain light with sustained
speeds generally ranging from 2-5 kt. Winds will be generally
variable to start before prevailing out of an east-northeast
direction by tomorrow morning.

Outlook...

Saturday Night: No Operational Impact. NO SIG WX.
Sunday: No 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: Low Operational Impact. Slight Chance of SHRA.
Tuesday Night: Moderate Operational Impact. Chance of SHRA.
Wednesday: Moderate Operational Impact. Chance of SHRA.

&&

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

&&

$$

SYNOPSIS...NAS
NEAR TERM...NAS/Webb
SHORT TERM...Webb
LONG TERM...Speciale
AVIATION...Gant