506
FXUS61 KALY 081942
AFDALY

AREA FORECAST DISCUSSION
National Weather Service Albany NY
342 PM EDT Wed May 8 2024

.SYNOPSIS...
Lingering showers or thunderstorms end this evening and a cold front
tracks through the region, with cooler weather expected Thursday
through the weekend. Chances for showers increase Thursday afternoon
and night through the weekend. It looks like we trend back towards
drier and slightly warmer conditions for the beginning of next week
before chances for showers increase again by midweek.

&&

.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
As of 3:40 PM EDT...Potent uper shortwave can be seen on GOES
16 water vapor imagery tracking into upstate NY, and surface
analysis shows an associated area of low pressure centered near
the southeastern Adirondacks. A pre-frontal trough and
associated dew point boundary are currently moving through the
region, and have sparked a few showers and thunderstorms
especially across the southern Berkshires. A couple of these
storms have been severe warned, with SPC mesoanalysis showing
1000 to 1500 J/kg of SBCAPE here overlapping with over 60 kt of
deep-layer shear. These storms should move off to our east into
New England within the next hour. The threat for severe weather
diminishes behind the dew point boundary, as instability should
decrease with much drier low-level air moving into the region.
Current satellite imagery also shows a more suppressed cu field
for areas already in this drier air, further increasing
confidence that the window for severe weather will not last
beyond the next hour or so.

However, winds become gusty, potentially at 30 to 40 mph, for a
brief period between now and sunset behind the dew point
boundary with deep boundary layer mixing. Daytime highs will be
in the 70s for most of the region, with portions of the Mid
Hudson Valley topping out around 80.

Additional showers and thunderstorms are expected to develop
across the Mohawk Valley and Adirondacks this afternoon and
early evening as the main upper shortwave tracks into the
region, providing forcing for ascent. Any storms here are not
expected to be severe, and showers/storms likely taper off
within a few hours of sunset this evening.

Tonight, the upper shortwave and associated surface low track
from upstate NY off the New England coast. The system`s cold
front will track through the region tonight, making it to around
the I-84 corridor by 12z. Any areas ahead of the cold front
could see some patchy fog tonight, especially for any areas that
receive a shower/storm this afternoon. North and west of the
cold front, advection of drier and cooler air should prevent
much fog. Lows will range from the 40s for the high terrain to
mid/upper 50s near the I-84 corridor.

&&

.SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
Tomorrow starts off relatively cool, especially across the
northern portions of our forecast area. It will also be dry to
start the day with a ridge of high pressure at the surface
beneath confluent flow aloft extending over our region. However,
a positively tilted upper trough with several embedded shortwave
disturbances rotating around it dips into the Great Lakes
region. The surface cold front continues its track southwards,
and an area of low pressure tracks eastwards from the Ohio
valley along the low-level thermal gradient beneath the left
exit region of the upper jet. This will bring increasing shower
chances in the afternoon and especially overnight, mainly for
areas along and south of I-90. Precipitation does not look as
widespread as it did at this time yesterday, especially tomorrow
afternoon. If current forecast trends continue, PoPs may have to
be trimmed back even more tomorrow. Temperatures will be in the
50s to 60s for highs tomorrow, and drop into the 40s tomorrow
night. A few wet snowflakes could mix in across the southern
Greens late tomorrow night, but little to no accumulation is
expected.

Friday and Friday night...Forecast confidence remains lower than
we would like for this timeframe. The upper trough takes on a
neutral to even negative tilt, and the surface low tracks to our
south off the Mid-Atlantic coast. At the same time, an inverted
trough will extend back north and west into central NY. We will
likely see showers or a period of steady rain for areas near the
inverted trough, but exactly how far north and east this feature
and the associated precip makes it remains somewhat uncertain at
this time. The best chance for rain therefore appears to be from
Albany south and west. Here, likely to categorical PoPs were put
in the forecast, with chance PoPs further north and east.
Precipitation chances diminish Friday night as the surface low
moves off to the east, but will keep slight chance to chance
PoPs around with the upper trough axis moving overhead. Friday
will be quite cool, with highs the 40s for many high terrain
areas with 50s for the lower elevations. Friday night lows will
generally be in the 40s, with some upper 30s in the high terrain
areas. A couple wet snow flakes could mix in across the highest
peaks of the ADKs, southern Greens, and Catskills with any
lingering light showers.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
Long term period begins at 12z Saturday with another upper shortwave
approaching from the west. This shortwave will close off aloft at it
moves over our area, which will slow the forward progress of the
large-scale trough causing it to remain overhead through most of the
weekend. The surface low associated with the upper shortwave weakens
as it moves into our area before redeveloping well or our east over
the Atlantic. With the surface low and upper trough nearby all
weekend, temperatures will likely be on the cool side, mainly in the
50s (terrain) to 60s (valleys). It will be mainly cloudy with
chances for showers each day, although we will see scattered showers
as opposed to an all-day rain.

We may dry out Sunday night into Monday as upper confluence and a
ridge of high pressure briefly build over the region, although an
upper shortwave and associated cold front may bring additional
chances for showers Monday afternoon into Tuesday for the norther
half of our forecast area. The track of this feature is far from set
in stone, so at this time till mention chance PoPs north of I-90 and
work to refine the timing/location of any precip over the next few
days. Forecast confidence decreases for the Tuesday into Wednesday
timeframe, as another storm system will be developing upstream and
may eventually track into our region towards the end of the long
term period. Will mention chance PoPs Tuesday afternoon into
Wednesday. Monday through Wednesday will be warmer, with more sun
than over the weekend and a southerly component of the flow helping
to advect warmer air into the region.

&&

.AVIATION /19Z WEDNESDAY THROUGH MONDAY/...
Through 18z Thursday...Low level stratus clouds have been
stubborn to scour out today, with BKN-OVC cigs finally becoming
SCT in the past hour at KALB/KGFL/KPSF. So VFR conditions
should generally prevail for the rest of the afternoon. A cold
front will move across the region later this afternoon. Widely
scattered SHRA/TSRA will continue to develop ahead of the front
this afternoon. At this time, radar indicating main area for
development has been just north/west of KGFL, so will mention a
TEMPO for MVFR conditions there. Activity looks to be more
sparse at KALB/KPSF, so will mention VCSH for now and monitor
trends for possible additional convection. Any SHRA/TSRA should
remain north of KPOU.

The threat for any SHRA/TSRA should end by early this evening,
with dry conditions then expected. Within the developing cold
advection regime overnight, an increase in low level stratus
clouds may occur. Confidence in coverage/heights is low at this
time, with mainly MVFR cigs anticipated. Cig heights should
increase to VFR levels Thursday morning, but with BKN-OVC cigs
still expected.

Winds will become westerly between 18z-19z and increase to
around 10-15 kt with gusts around 20-25 kt developing. Winds
could also be stronger associated with any TSRA. Winds will
become northwest this evening around 6-12 kt, then northerly by
early Thursday morning.

Outlook...

Thursday Night: High Operational Impact. Likely SHRA.
Friday: High Operational Impact. Likely SHRA.
Friday Night: Moderate Operational Impact. Chance of SHRA.
Saturday: Moderate Operational Impact. Chance of SHRA.
Saturday Night: Moderate Operational Impact. Chance of SHRA.
Sunday: Moderate Operational Impact. Chance of SHRA.
Sunday Night: Low Operational Impact. NO SIG WX.
Monday: Low Operational Impact. Slight Chance of SHRA.

&&

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

&&

$$

SYNOPSIS...Main
NEAR TERM...Main
SHORT TERM...Main
LONG TERM...Main
AVIATION...JPV