-- Discussion containing changed information from previous version are highlighted. --
719
FXUS61 KALY 040753
AFDALY

AREA FORECAST DISCUSSION
National Weather Service Albany NY
353 AM EDT Thu Jul 4 2024

.SYNOPSIS...
Warm and more humid conditions are expected for
Independence Day today with some spotty showers or thunderstorms
around. With a frontal boundary around, the threat for a shower or
thunderstorm will linger into Friday, with continued warm and muggy
conditions.  Hot and humid conditions are expected on Saturday with
more thunderstorms around once again.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
-- Changed Discussion --
As of 353 AM EDT...A nearly stationary frontal boundary is
located west of the region over the eastern Great Lakes. A weak
pre-frontal surface trough is in place over Upstate New York.
MRMS imagery shows a broken line of showers, mainly light in
intensity, stretching from the western and central Adirondacks
back to the southwest across central New York and the Finger
Lakes and towards western New York. Over the next few hours,
some of this activity looks to spread towards the Lake George
and Saratoga areas by late in the overnight and towards
daybreak. Instability is limited at this time, with some low
amounts of elevated CAPE located back across western New York.
While a stray rumble of thunder can`t be ruled out within any
heavier downpours, any thunderstorm activity looks fairly
isolated through daybreak.

Otherwise, skies will remain partly to mostly cloudy across the
region through the early morning hours. While winds have
diminished in sheltered areas within the high terrain, most
larger valley areas continue to see breeze southerly winds at
this time. While dewpoints remain fairly low in the 50s, they
will be creeping up towards sunrise.

A few brief lingering showers may continue to spread across far
northern areas early this morning, but most areas should be dry
to start the 4th of July with a partly sunny sky. Dewpoints will
be inching up this morning and it will be starting to feel more
muggy out with temperatures quickly warming into the 80s by the
late morning hours.

During the afternoon hours, CAMs suggest a few isolated showers
or t-storms may develop, mainly south of the Capital Region, as
the weakening boundary settled eastward over the area. This
front will be washing out over the area, but may provide enough
of a focus for some diurnally-forced convection. While there
will be some instability, CAPE values don`t look too large, with
values under 1000 J/kg and lapse rates will be fairly poor. As
a result, any thunderstorms look to remain fairly brief and
disorganized and no severe storms are anticipated, although
brief heavy downpours will be possible.

Highs today look to reach the mid to upper 80s in valley areas,
with upper 70s to low 80s in the high terrain.
-- End Changed Discussion --

&&

.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
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Any convection should start to diminish after sunset this
evening, allowing for mainly quiet conditions for tonight. It
will be more humid than recent nights, so some patchy fog may
developed in some typical sheltered areas. Otherwise, skies will
be partly cloudy through the overnight with lows in the 60s.

On Friday, a slow moving surface boundary will be near or just
south of the area, but will be lifting northward as a warm front
by later in the day and into Friday night. Meanwhile, the region
will be under the influence of south to southwest flow aloft,
with an upper level disturbance well west of the region over the
Midwest. With plenty of warm temps in place aloft, it will be a
rather hot day on Friday, with valley areas reaching into the
upper 80s to low 90s. Dewpoints will continue to creep up
through the 60s and may even reach into the low 70s for valley
areas. This could allow heat index values to come close to 95
degrees by afternoon in some valley areas, so will need to watch
this closely in case any heat advisories will be needed.

Although the morning should be fairly dry, the warm and muggy
air mass and nearby boundary could allow for some afternoon
convection to develop. CAMs have different ideas regarding the
exact placement and coverage of storms, but there will be the
potential for some showers and t-storms to develop, especially
for southern areas. With the warm temps aloft, lapse rates won`t
be overly impressive, but there should be some instability in
place (00z SPC HREF shows around 1000 J/kg by later in the day).
Can`t totally rule out a stray severe storm due to precip
loading, but the lack of upper level support and poor lapse
rates should help prevent a more widespread threat for strong
convection on Friday. Also, coverage of convection may be more
isolated to scattered during the day on Friday. However, there
may be more coverage around by the overnight hours as the
frontal boundary lifts northward, although surface-based
instability looks to be more limited during the overnight hours
due to a nocturnal inversion in place near the surface. With
higher PWATs in place, any storms on Friday night could contain
heavy downpours, so a localized threat for ponding will be
possible with any convection. It will be a mild and muggy night
on Friday night with lows in the mid 60s to low 70s.

On Saturday, upper level shortwave trough will be lifting from
the Upper Great Lakes and across southern Canada. A weak surface
cold front will be trying to push across the area from the west.
Some additional convection is expected on Saturday, with the
greatest coverage probably for eastern and southern areas and
mainly earlier in the day. Models continue to have differing
ideas regarding exact coverage/placement once again as well.
There could be a localized severe threat on Saturday, but the
best heights falls and upper level dynamics are pretty far off
to the northwest. With PWATs around two inches, heavy downpours
may be a bigger threat, depending on where storms form and if
any training occurs. Otherwise, it will be another warm and very
humid day (dewpoints well into the 70s possible) with heat index
values nearing advisory criteria in valley areas.

Behind the front, somewhat drier air tries to move in for
Saturday night as dewpoints start to lower. The threat for
showers/t-storms looks to lower on Sat night with lows back down
into the 60s under a partly cloudy sky.
-- End Changed Discussion --

&&

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
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Dry conditions return for the start of the long term forecast period
as surface high pressure approaches from the west and shortwave
ridging builds in aloft. Saturday`s cold front will become
positioned just to the south of the region as a diffuse, stationary
boundary but will pose no threat of precipitation Sunday into Monday
a dry air filters in at the mid-levels and subsidence increases as a
result of the high. Sunday`s high temperatures will be the cooler of
the two dry days with mid 70s to low 80s at higher elevations and
mid to upper 80s in large valley areas. Monday will then feature
highs in the upper 70s to low 80s above 1500 ft with more widespread
mid/upper 80s to pockets of low 90s in the Hudson Valley courtesy of
the slight increase in geopotential heights aloft and the surface
anticyclone looking to be directly over the region. Luckily, with
dewpoints anticipated in the upper 50s to mid 60s, heat indices
Monday should not reach Heat Advisory criteria. Lows Sunday night
will be in the mid 50s to low/mid 60s.

The aforementioned surface high will begin its southeast exit from
eastern New York and western New England beginning Monday night and
heights aloft will begin to decrease in advance of a disturbance
upstream. Conditions throughout the night will remain largely dry,
however, with low temperatures Monday falling into the 60s.
Attention then shifts to Tuesday and Wednesday as a frontal system
and associated shortwave look to be the source of potentially
widespread showers and some thunderstorms. Guidance is in fair
agreement that a surface low will track from the Great Lakes north
and east into southeast Ontario/southwest Quebec as the
aforementioned shortwave rotates through the Great Lakes and Ohio
Valley Tuesday. A secondary surface low also looks to potentially
develop within the Mid-Atlantic region, providing an extra source of
convergence near the area of PVA within the shortwave to enhance
lift ahead of the system`s cold front. Showers look to begin Tuesday
evening to the north and west of Albany, overspreading to the south
and east throughout the night and into Wednesday. Long range
guidance indicated some weak to moderate instability across portions
of the region that could aid in some embedded rumbles of thunder
Tuesday evening into Wednesday, but confidence is not yet high in
the likelihood of severe convection potential. We will continue to
monitor this potential as lead time decreases.

High temperatures Tuesday will be similar to those of Monday
especially if showers hold off until the evening/overnight hours as
current guidance suggests. Again, heat indices look to fall below
Heat Advisory criteria. Low temperatures Tuesday night will be
primarily in the 60s. Wednesday will then be a cooler day with 70s
anticipated above 1000 ft and low to mid 80s in valley areas.
-- End Changed Discussion --

&&

.AVIATION /07Z THURSDAY THROUGH MONDAY/...
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Through 06z Friday...Flying conditions are VFR across all
terminals this morning which is anticipated to continue through
the remainder of the overnight period. IR satellite imagery
shows some high and mid/low-level clouds streaming into the
region ahead of a cool frontal boundary, but showers have been
kept at bay of the terminals thus far this morning. A few light
showers are possible later this morning, closer to daybreak, but
little impact to flying conditions is expected.

While only the KALB METAR indicates a high-level ceiling as of
this update, lower-level, though still VFR, ceilings are
anticipated to develop at all terminals throughout the morning
as the aforementioned boundary continues to slide south and east
into the region. Then, later this afternoon, some widely
scattered showers are possible especially at KPOU and KPSF but
cannot be ruled out at KALB. Precipitation rates look to be
light enough to not cause impact to visibility at KALB, but some
heavier downpours will be possible at KPOU and KPSF which could
lead to MVFR visibilities. At this time, forecast soundings are
not pointing towards MVFR ceilings, but this could certainly
change with future updates to guidance. Will monitor these
updates and make adjustments if need be with coming TAF cycles.

Showers look to be the most likely between 18-22z this
afternoon. Once shower activity has concluded, any deviations
from VFR ceilings/visibility should improve back to favored
flying conditions through the remainder of the 06z TAF period.
Winds throughout this cycle will be relatively light and
variable at sustained speeds ranging from 5-10 kt.

Outlook...

Friday Night: High Operational Impact. Likely SHRA...TSRA.
Saturday: Moderate Operational Impact. Likely SHRA...TSRA.
Saturday Night: Low Operational Impact. Slight Chance of SHRA...TSRA.
Sunday: No Operational Impact. NO SIG WX.
Sunday Night: No Operational Impact. NO SIG WX.
Monday: No Operational Impact. NO SIG WX.
Monday Night: No Operational Impact. NO SIG WX.
Tuesday: Moderate Operational Impact. Chance of SHRA...TSRA.
-- End Changed Discussion --

&&

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

&&

$$

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