575
FXUS61 KALY 211909
AFDALY

AREA FORECAST DISCUSSION
National Weather Service Albany NY
309 PM EDT Sat Sep 21 2024

.SYNOPSIS...
Continued dry and seasonably warm conditions through tomorrow,
then temperatures trend cooler through Monday and Tuesday. Our
long stretch of dry weather then comes to an end by the middle
to end of this week as unsettled conditions develop and chances
for showers increase Tuesday through the end of the week.

&&

.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
Lots of sun across the region with light winds and those trends
should continue based on satellite pictures and radar. Just
minor adjustments to temperatures and sky cover through this
afternoon.

PREVIOUS DISCUSSION:
Stratus clouds redevelop this evening, especially in western
New England, as our backdoor front washouts out as it slides
further west through the Mohawk Valley/western Adirondacks and
our coastal low continues to slowly exit southward. High
pressure centered in eastern Quebec expands and gains control of
the Northeast. Given anticipated cloud coverage, did not
include any fog mention. Overnight lows remains a bit mild with
lows in the upper 40s to mid 50s thanks to clouds.

&&

.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/...
Upper level ridging from the Ohio Valley amplifies as it builds
into western/central NY on Sunday providing increasing
subsidence that allow early clouds to give way to clearing
as high pressure over Quebec maintains control at the sfc. All
of these features will give us a pleasant Sunday and first day
of autumn with high temperatures reaching into the low to mid
70s in the valley with mid to upper 60s in the higher terrain
and hill towns. Temperatures cool off noticeably towards sunset
given clear skies.

Clear skies continue Sunday night supporting efficient
radiational cooling but as the upper level ridge axis flattens
and slides into western New England, cirrus clouds should spread
eastward overnight. Still expecting a chillier night as cirrus
clouds likely will not hinder radiational cooling much with temperatures
dropping into the mid to upper 40s for much of the area (around
50 in the immediate valley areas).

Upper level ridging continues to flatten on Monday as a weak
shortwave trough in Ontario and associated weak warm front from
western PA/NY pushes eastward. High pressure centered in
eastern Quebec maintains a strong hold over the Northeast as
the warm front remains to our west. Thus, only expecting
increasing clouds through the day Monday with most showers
remaining to our west. Included slight chance and chance POPs
in the southern Adirondacks Monday P.M given some uncertainty but
the best warm air/moisture advection remains to our west. Thus,
POPs may may very well be removed in future updates. Otherwise,
southeast winds become a bit breezy at times as the pressure
gradient tightens between the Canadian high and weak low
tracking through the southern Great Lakes. High temperatures
will end up a few degrees cooler compared to the weekend with
daytime highs reaching into the mid to upper 60s with low 70s in
the valley.

Skies remain cloudy Monday night which will keep temperatures a
bit elevated in the low to mid 50s in the valley with upper 40s
in the higher terrain and hill towns. As the sfc warm front near
closers, the leading edge of the stronger warm air/moisture
advection along the sfc convergence advances eastward leading
to increasing POPs from west to east Monday night. However, with
high pressure keeping a strong hold over the Northeast, we
capped POPs at only chance in eastern NY with slight chance in
western New England as some guidance indicates showers weaken
or even diminish as they run into the sfc high. Will continue to
monitor trends.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
A wetter, unsettled period continues through much of next week as
persistent upper-level troughing develops over much of the eastern
CONUS. An initial upper trough over the Northern Plains on Tuesday
will track eastward, with ensemble guidance continuing to suggest
troughing will eventually move into Southeast Canada while a cutoff
low develops somewhere from the Southern Plains into the Ohio Valley
Thursday into Friday. Details aside, troughing moving toward the
Northeast will see repeated chances for rain, initially arriving
from the west on Tuesday, and spreading eastward through Wednesday
and Thursday. Chances for additional showers on Friday remain
dependent on the relative placement of upper lows over New England
and the MS/OH Valleys, and are a low confidence forecast at this
lead time.

Beneath persistent upper troughing, temperatures look to remain
steady at seasonable levels through the period. Afternoon highs will
reach the upper 50s to mid 60s in high terrain and mid 60s to low
70s at lower elevations each of Tuesday through Friday afternoons,
while lows in the upper 40s to mid 50s are expected Tuesday through
Friday nights.

&&

.AVIATION /19Z SATURDAY THROUGH THURSDAY/...
Through 18Z Sunday...VFR conditions are expected through at
least sunset, despite varying levels of clouds with Cigs between
3500-5000 FT AGL, and also around 10,000 FT AGL.

After sunset, patches of mid level clouds are expected. In
between these cloud patches, there may be some patchy ground fog
developing, especially after 08Z/Sun. Low confidence overall in
any one particular TAF site reaching IFR/LIFR Vsbys/Cigs,
although chances may be slightly higher at KGFL and KPOU should
prolonged breaks in the mid level clouds occur.

MVFR Cigs may develop at KPSF and prevent lower Cigs/Vsbys later
tonight through around 14Z/Sun.

After any patchy fog lifts 12Z-14Z/Sun, occasional cloud patches
will continue through midday Sunday, with Cigs mainly between
3500-5000 FT AGL, with Cigs more persistent at KPSF.

East to northeast winds 5-10 KT this afternoon, becoming
light/variable tonight, then east to northeast by mid to late
Sunday morning again at 5-10 KT.

Outlook...

Sunday Night: No Operational Impact. NO SIG WX.
Monday: No Operational Impact. NO SIG WX.
Monday Night: Moderate Operational Impact. 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.
Wednesday Night: High Operational Impact. Likely SHRA.
Thursday: Moderate Operational Impact. Chance of SHRA.

&&

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

&&

$$

SYNOPSIS...NAS
NEAR TERM...NAS/Speciale
SHORT TERM...Speciale
LONG TERM...Picard
AVIATION...KL