487
FXUS61 KALY 041723
AFDALY

AREA FORECAST DISCUSSION
National Weather Service Albany NY
123 PM EDT Tue Jun 4 2024

.SYNOPSIS...
Warm weather persists today and tomorrow with a warm
airmass remaining in place across the region. With high pressure
remaining generally dominant, conditions will also be primarily dry
for these next two days outside of some isolated to widely
scattered, high-elevation showers and thunderstorms. A pattern shift
ensues for the latter portion of the week with a strong low pressure
system approaching from the west. This system will bring cooler
temperatures than recent days as well as several rounds of
widespread showers and thunderstorms into the weekend.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
.Update...As of 1:20 PM EDT...Temperatures have now risen into
the 80s for most of our valley areas. Skies have remained partly
to mostly clear this morning, but we are now seeing more
development to the cu field especially over the high terrain. A
few isolated showers have developed over the high terrain areas,
and these areas will continue to experience some isolated
showers or a non-severe thunderstorm this afternoon with mainly
dry conditions elsewhere. Again, just minor updates with this
ESTF as previous forecast remains in good shape...

.Previous...Throughout the day today, the ridge aloft looks to
weaken slightly and slowly begin to shift east. High clouds are
expected to increase as a result of a nearby system to our
north and west drifting closer eastward, but coverage should
maximize at partly cloudy. Winds will gradually begin to back to
the south, gradually increasing the humidity across the region
due to mild moisture advection. That said, dewpoints will remain
in the mid/upper 50s with pockets near 60 and with highs
anticipated to reach the upper 70s to mid/upper 80s, conditions
will still feel relatively comfortable.

While most areas will remain dry throughout the day today, some
diurnally-driven, isolated to widely scattered showers and a
few thunderstorms could pop up in higher terrain areas due to
upslope flow and a weak, nearby disturbance. However, with very
limited forcing, low instability (generally less than 1000
J/kg), and low shear, any thunderstorms that develop will be
sub-severe.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/...
Any ongoing showers and thunderstorms should swiftly die out
upon the loss of diurnal heating tonight, giving way to dry
conditions once again for the overnight period tonight. Clouds
are expected to stick around, keeping skies partly cloudy and
low temperatures subsequently mild with mid/upper 50s to 60
likely.

The upper ridge remains dominant across the region into
Wednesday despite the surface high shifting out of the region to
the east-southeast. Some breaks in cloud coverage are possible
Wednesday morning into the early afternoon courtesy of
subsidence from the exiting high, but with upper-level troughing
swiftly approaching from the west, clear breaks will quickly
fill back in later Wednesday afternoon. That said, skies will
likely remain only partly cloudy through prime daytime heating
hours such that high temperatures Wednesday reach the upper 70s
to mid 80s with pockets of upper 80s possible in valley areas.

Southerly flow Wednesday will ensure humidity continues to
increase across eastern New York and western New England.
Dewpoints are anticipated to increase to the mid/upper 50s to
low 60s. With warm, moist air present across the region, there
will be chances for additional, diurnally-driven showers and
thunderstorms once again Wednesday. However, with an overall
lack of forcing and continued weak buoyancy (SBCAPE < 1000
J/kg), storms should remain sub-severe.

The remainder of the short term period will see the beginning of
a pattern shift across the region with the approach of a strong,
upper-level low pressure system from the northwest. Clouds will
continue to increase throughout the overnight period Wednesday,
keeping low temperatures in the upper 50s to low 60s. Some
showers will be possible beginning early Thursday morning,
mainly west of the Hudson, as upper-level troughing associated
with the upper, cut-off low begins to encroach western New
York. As the upper low continues to deepen and sink towards the
upper Midwest through Thursday, its leading upper trough will
continue to dig further across the region, leading to showers
becoming more widespread. Embedded thunderstorms will be
possible across the region Thursday, however, because of
continued uncertainty with the track of the system, it is too
early to determine storm severity and the areas at greatest risk
for convection. Confidence has grown, however, in the widespread
nature of showers for Thursday, so included likely to
categorical PoPs with mention of slight chance to chance
thunder through Thursday evening. There seems to be a general
consensus in the guidance to indicate a dry slot that moves
into the region Thursday night, bringing a stop to widespread
rain, so decreased PoPs to slight chance to chance during this
time. Highs Thursday will be several degrees cooler than today
and Wednesday with upper 60s at higher elevations to upper 70s
in valley areas. Lows Thursday night will be in the low 50s
above 1500 ft to upper 50s and pockets of low 60s in valley
areas.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
Unsettled weather expected through the period as an upper
disturbance tracks around the southern periphery of an upper cut off
low in the Great Lakes and OH Valley Friday into Saturday. Then the
primary upper cut off low drifts slowly through our region the rest
of the weekend, and lifts northeast Monday and beyond.

There is a surprising agreement in sources of guidance/ensembles
with the evolution and track of the leading upper disturbance and
the upper cut off low. Even with the agreement, the fine details of
where the most clouds and chances for showers and isolated
thunderstorms sets up, will still likely be adjusted a number of
times before the weekend.

As is typical with upper closed and cut off lows, showers and
thunderstorms form late in the morning and early afternoon. The most
coverage of clouds, showers and isolated thunderstorms should be
each afternoon due to the instability proximate to the upper cold
pool. Breaks in the clouds and more isolated shower activity at
night and early morning. So, not the best bunch of days for outdoor
activities, including what could be a cool weekend with intervals of
afternoon showers and isolated thunderstorms.

Highs Friday in the 70s with some mid to upper 60s in the southern
Adirondacks and near 80 mid Hudson Valley. Highs Saturday and Sunday
in the lower to mid 70s with mid 60s higher terrain. Highs Monday in
the mid to upper 70s with around 70 higher terrain and near 80 mid
Hudson Valley.

&&

.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
Visible satellite imagery, web cam imagery and surface observations
show that some diurnal cumulus has been developing across the
region, along with some scattered cirrus clouds as well.  Through
the afternoon hours, flying conditions look to remain VFR with sct-
bkn cigs around 6 kft and some passing high clouds as well.  Radar
imagery is showing some isolated showers trying to form over the
highest terrain, but CAMs suggest this will be very isolated today,
so won`t mention in the TAFs at this time.  Through the rest of the
day, surface winds will continue to be light, mainly 5 kts or less,
from a south to southeasterly direction.

For tonight, some lingering mid and high level clouds are expected
for most sites.  Flying conditions should continue to be VFR with no
precip. If enough clearing occurs, some radiational fog may form
late in the overnight at KPOU, but this is rather uncertain at this
time. Winds will continue to be very light or calm for all sites.

On Wednesday, it looks VFR for much of the day once again with just
some bands of mid level clouds.  Some diurnally-forced clouds around
6-8 kft may develop once again as well.  Any precip looks to hold
off until Wed night.  Southerly winds will be 5 to 10 kts on
Wednesday.

Outlook...

Wednesday Night: High Operational Impact. Likely SHRA...TSRA.
Thursday: High Operational Impact. Definite SHRA...TSRA.
Thursday Night: Moderate Operational Impact. Chance of SHRA...TSRA.
Friday: High Operational Impact. Likely SHRA...TSRA.
Friday Night: Moderate Operational Impact. Chance of SHRA...TSRA.
Saturday: Moderate Operational Impact. Likely SHRA...TSRA.
Saturday Night: Moderate Operational Impact. Chance of SHRA...TSRA.
Sunday: Moderate Operational Impact. Chance of SHRA...TSRA.

&&

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

&&

$$

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