093
FXUS61 KALY 041421
AFDALY

AREA FORECAST DISCUSSION
National Weather Service Albany NY
1021 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/...
Mostly sunny north of the Mohawk Valley into southern VT. Clouds
and a few sprinkles From the Mohawk Valley and Berkshires and
points south. Weak frontal boundary will be the focus for
isolated to scattered showers and thunderstorms this afternoon,
mainly south of the Schoharie Valley, Capital Region and
southern VT based on area soundings, radar and satellite data.
Just minor adjustments to sky cover, rain chances and
temperatures through the afternoon.

PREVIOUS DISCUSSION:
A nearly stationary frontal boundary is located west of the
region over the eastern Great Lakes and western New York. IR
satellite imagery shows sky cover varying between partly to
mostly cloudy, although most of the clouds are mid and high
level. Some spotty showers are ongoing early this morning across
the central and eastern Adirondacks, as well as across parts of
the Catskills, mid Hudson Valley and NW CT. A few of these
showers could linger over the next few hours, but any showers
will be fairly brief and most areas should be dry to start the
4th of July. 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.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
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.

&&

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
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.

&&

.AVIATION /14Z THURSDAY THROUGH MONDAY/...
Through 12z Friday...VFR conditions prevail across all terminals
this morning as patchy clouds increase throughout the area.
Flying conditions look to remain within VFR thresholds
throughout much of the duration of the 12z TAF period forecast
soundings showing sufficient dry air in the mid to upper levels.
That said, a weak surface boundary will cross through the region
this afternoon which could bring showers and possibly a few
thunderstorms to KPOU/KPSF and possibly KALB. Any showers that
develop within the vicinity of KALB should be relatively light
so maintained VFR conditions within the TEMPO for showers
between 19-22z. KPOU and KPSF, however, could see some heavier
downpours so MVFR visibility was added to their TEMPOs between
19-23z. Upon the conclusion of shower and thunderstorm activity
this evening with the loss of daytime heating, VFR conditions
will prevail once again and should last through the remainder
of the 12z TAF period. Some patchy fog could develop across the
area tonight, but kept this out of the TAFs until confidence
increases as development will likely be dependent on where it
rains today.

Winds throughout the period will be light and variable with
sustained speeds of 5 to 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.

&&

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

&&

$$

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