066
FXUS61 KALY 030523
AFDALY

AREA FORECAST DISCUSSION
National Weather Service Albany NY
123 AM EDT Thu Jul 3 2025

.SYNOPSIS...
Tranquil weather persists into the overnight period
tonight, making for pleasant, early July conditions. Tomorrow,
showers and thunderstorms are expected to impact the region once
again with isolated to scattered chances of these becoming severe.
Dry conditions return for the Fourth of July Holiday, with a much
drier airmass making for ideal conditions for summer activities
before the heat returns this weekend.

&&

.NEAR TERM /THROUGH TODAY/...
Zonal flow aloft paired with high pressure nosing northward at
the surface has made for quite the pleasant day today with
partly cloudy skies and temperatures widely in the mid 70s to
low 80s. Tranquility will persist into tonight with high
pressure remaining in place whilst a mid- to upper-level trough
begins to dig south and east, extending off an upper low
traversing the James Bay. With limited moisture around, clouds
should remain fairly limited so low temperatures will radiate
down to the upper 50s to low 60s.

&&

.SHORT TERM /TONIGHT THROUGH SATURDAY/...
Key Message:

- Isolated to scattered severe thunderstorms will impact the
  region tomorrow with strong to locally damaging wind gusts and
  large hail the primary hazards.

- SPC has introduced a Slight Risk (2 of 5) for much of the area
  as a result of increased confidence in storm occurrence and
  coverage.

Discussion:
Tomorrow, the aforementioned low will slide farther south and
east, becoming situated overhead whilst its associated
positively-tilted trough digs farther into the Northeast. An
embedded shortwave within the mean flow of the trough will force
the enhancement of height falls and increase cyclonic vorticity
advection despite the gradual weakening of its parent low.
Meanwhile, a surface low beneath the forward flank of the trough
will deepen just to our north as it tracks eastward. Surface
convergence will strengthen across eastern New York and western
New England as a weak surface wave precedes the low`s trailing
cold front, acting to further enhance forcing for ascent. Limited
cloud cover will provide plenty of sunlight to help the
atmosphere begin to destabilize early tomorrow morning with less
than recently, but still moderately humid air positively
contributing to this process.

Latest CAMs are rather varied in their depictions of the
coverage of convection tomorrow. Timing differences do exist as
well, though the consensus is a bit more consistent with a
potential late morning/early afternoon onset time. Therefore, we
will focus the discussion of uncertainty around coverage.

The high pressure that dominates the region today should not
pose much in the way of counteracting subsidence to ascent
tomorrow given its forced compression southward by the
southward-expanding area of surface low pressure and deepening
of the trough aloft. However, westerly to northwesterly flow
across the region will likely lead to downsloping and resulting
localized mixing or drying out of the lower levels especially in
valley areas. Therefore, what will already not be as humid of an
airmass as we`ve seen over the last several days will be made
even less so. It is very possible that the CAMs depicting less
coverage of storms tomorrow are incorporating more mixing than
others. To account for this possibility, we lowered dewpoints
tomorrow by a few degrees, bringing valley RH values largely to
low/mid 50s instead of the original NBM v 4.3 values which
ranged primarily in the mid 50s to low 60s in these areas. That
said, even those models whose solutions show greater coverage of
convection, generally keep storms on the scattered side. But
generally erred on the side of more scattered convection rather
than isolated given the potency of the upper trough and its
embedded shortwave; the enhanced surface convergence with both
the wave and trailing front; the presence of a cyclonically
curved upper jet whose left exit region looks to become
positioned across our area; and moderate instability and shear.

It is also for these reasons that the issuance of a Slight Risk
(Level 2 of 5) for severe weather was collaborated with both
neighboring offices and SPC. This new Slight Risk generally
reaches as far north as I-90 into the Saratoga Region and areas
south. Everything to the north remains within the Marginal Risk.
The greatest threat from severe thunderstorms tomorrow is
damaging wind gusts. With a wind field favoring acceleration
off the high terrain into valley areas; DCAPE values reaching
nearly 1000 J/kg; and steep low and mid-level lapse rates, wind
gusts reaching or exceeding 58 mph will be possible especially
within the areas enclosed in the Slight Risk. Additionally,
strong deep-layer shear; steep mid-level lapse rates; and
moderate instability drive the threat for large hail (1" in
diameter or greater) tomorrow. More or less straight hodographs
and flow perpendicular off the incoming boundary increase
confidence in the potential for individualized updrafts to
start, but, as latest CAMs also show, clustering could begin to
occur should storms begin to form and track near each other.
And, as previously stated, onset could occur as early as late
morning should the forcing from the surface wave and the upper
trough align that early.

All convection looks to conclude by late afternoon/early evening
tomorrow as the cold front completes its its passage through the
region. Highs tomorrow will be in the 70s to upper 80s. And though
troughing from the still weakening low will persist across the
region through Friday night, dry conditions will be maintained
as surface high pressure encroaches once again. The Fourth of
July Holiday will the be absolutely beautiful with ridging
beginning to build in aloft, the surface high strengthening, and
a drier airmass keeping hold of the region in the wake of the
front. It will be a perfect day for all outdoor summer
activities with highs in the 70s and 80s! Friday night and
Saturday, too, will be quite pleasant with high pressure
remaining in place to maintain tranquility. However, with a
southerly flow regime setting up again Saturday temperatures
will begin to increase before conditions become oppressive again
beginning Sunday. Highs Saturday will be in the upper 70s to
upper 80s. Lows Thursday night and Friday night will
predominantly be in the 50s.

&&

.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
Key Message:

- Oppressive heat returns Sunday into Monday with heat indices
  looking to reach the upper 90s especially throughout the
  Hudson Valley.

Discussion:
The extended forecast period will begin with a continuation of
dry conditions as high pressure at the surface and ridging aloft
dominate the region. Unfortunately, however, this will also
translate to the return of oppressive heat as southerly flow
advects another humid airmass across eastern New York and
western New England. Highs Sunday will largely range from the
80s to low 90s with heat indices reaching the upper 90s
especially throughout portions of the Hudson Valley. Monday will
be very similar, though a few degrees warmer in valley areas
with heat indices of upper 90s spanning more of the Hudson
Valley area than Sunday. Heat Advisories may be needed in the
near future, but will continue to hold off until confidence is
more certain.

A wave of surface low pressure and a weak shortwave will swing
trough the region Monday into Tuesday, bringing some showers
and thunderstorms once again. There are some timing differences
in terms of the ending of this precipitation, given the
differences in the depiction of the front, but general consensus
points to a stall of the front to our south which could allow
showers to linger for southern areas Tuesday. However, by
Tuesday night, dry conditions look to return with high pressure
and upper-level ridging returning. Highs Tuesday will be more
seasonable than Monday with values in the mid 70s to mid 80s. It
will also be more comfortable with heat indices close to the
actual air temperature. Lows throughout the extended period will
generally be in the 60s with some pockets of upper 50s at higher
terrain Saturday night and Tuesday night and pockets near 70
Sunday night and Monday night.

&&

.AVIATION /06Z THURSDAY THROUGH MONDAY/...
We start the TAF period with VFR conditions under clear skies
and calm winds. VFR conditions are forecasted to continue today
outside the chances for thunderstorms late this morning and
afternoon. Probabilities are still less than 30 percent for
impacts to TAF sites so continued to mention in PROB30 groups
IFR conditions with any thunderstorm that could pass through TAF
sites. One forecast change that latest forecast models are
showing is the thunderstorm activity could occur as early as
15z. Adjusted the PROB30 start time by one to two hours early to
account for this and continued consistency for end timing of
21-22z for thunderstorms. VFR conditions are in store for after
21z. Westerly winds are still on track for this morning and
afternoon becoming light and variable for tonight.

Outlook...

Thursday Night: No Operational Impact. NO SIG WX.
Independence Day: No Operational Impact. NO SIG WX.
Friday Night: No Operational Impact. NO SIG WX.
Saturday: No Operational Impact. NO SIG WX.
Saturday Night: No Operational Impact. NO SIG WX.
Sunday: No Operational Impact. NO SIG WX.
Sunday Night: No Operational Impact. NO SIG WX.
Monday: Moderate Operational Impact. Chance of SHRA...TSRA.

&&

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

&&

$$

SYNOPSIS...Gant
NEAR TERM...Gant
SHORT TERM...Gant
LONG TERM...Gant
AVIATION...Webb