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091
FXUS61 KALY 042324
AFDALY

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

.SYNOPSIS...
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Any lingering showers and thunderstorms diminish this evening
with the loss of daytime heating. Tomorrow will be another warm
day with mainly dry conditions. Then, our weather pattern will
trend cooler and wetter for Thursday through early next week
with a cutoff upper low expected to be located nearby.
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&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
.UPDATE...Most of the pop-up convective showers have been just
to the east of a subtle boundary oriented N-S near the NY/New
England border, over the higher terrain of western New England.
Have increased PoPs to low chance to account for this widely
scattered activity, with a handful of pulse-type cells. A few
have had some limited lightning as well. Brief downpours can be
expected, with a quick 0.50-1.50" of rain in isolated spots.
Otherwise, dry conditions should persist other than a few rogue
showers across the rest of the area into this evening with
continued warm temperatures.

.PREV DISCUSSION[0355]...Surface high pressure remains located
off to our east near Cape Cod, with ridge axis aloft just to the
west of our area. A weak upper impulse combined with terrain-
driven circulations has allowed for a few showers to develop
over the high terrain this afternoon. Showers are isolated in
nature, and we haven`t seen any thunder yet likely due to some
mid-level capping as seen on the 12z KALY sounding. However, a
few rumbles of thunder can`t be ruled out between now and sunset
with model forecast soundings suggesting some modest
instability in place. Showers could be briefly heavy in nature
and are slow-moving, but are relatively short-lived due to the
lack of vertical wind shear. Therefore, not expecting any hydro
issues through this evening. Temperatures are at or near daytime
highs for areas that have not seen convection, with most valley
areas having climbed well into the 80s.

This evening, showers and storms should diminish fairly quickly
after sunset with the loss of daytime heating and most of the
night remaining dry once these showers dissipate. We remain
under ridging aloft and the surface high remains off to our
southeast. There will be a few more mid and high clouds compared
to last night, but areas that saw rain this afternoon could see
some patchy fog develop after midnight. Generally stayed near
NBM/MOS guidance for overnight lows with most places dropping
into the 50s.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY/...
Tomorrow, we remain under the upper ridge, although the ridge
begins to weaken as a closed upper low tracks from south-central
Canada towards the western Great Lakes. The surface high remains
to the southeast of our area, which will lead to continued
south/southwest flow and advection of warm moist air into our
area. Therefore, tomorrow looks to be another warm and slightly
muggy day with highs similar to those from today. Heat index
values could approach 90 degrees tomorrow, but are not expected
to reach heat advisory criteria. It should be partly cloudy
tomorrow and mostly dry, aside from a few isolated afternoon
showers or a non-severe thundershower over the high terrain
areas.

Tomorrow night and Thursday...The upper trough continues to
deamplify as the upper low tracks into the western Great Lakes
region. The ridge axis slides off to our east by Thursday
afternoon with falling heights aloft. A cold front will approach
from the west Thursday afternoon/evening, and a period of
showers with embedded thunderstorms is expected ahead of this
cold front late Wednesday night and Thursday. PWATs increase to
1.5-1.75" and diffluent flow aloft will provide forcing for
ascent. There could be some locally heavy pockets of rain late
Wednesday night into Thursday morning, which could result in
the typical ponding of water in urban/poor drainage
areas. However, we are not expecting widespread hydro issues or
flash flooding with antecedent dry conditions, relatively fast
storm motions, and overall rainfall amounts through Thursday
generally expected to max out at 1-1.25". Wednesday night will
be warmer with lows in the 50s to 60s. Thursday will feature
highs mainly in the 70s.

THursday night and Friday...The cold front tracks through our
region Thursday night or Friday, with the upper low tracking in
the Great Lakes region. The steadiest rain will end by Thursday
evening with a trend towards drier conditions Thursday night.
However, showers and possibly a few thunderstorms redevelop
during the day Friday with diurnal heating thanks to the cold
pool aloft that will be located just to our west and some
enhanced lift from the left exit of the upper jet extending
around the base of the upper low.The deeper moisture will be off
to our east at this point, so showers do not look to be
particularly heavy and the threat for hydro concerns remains
low. Thursday night will be cooler with lows in the 50s. Highs
Friday will be in the 60s (terrain) to 70s (valleys) with partly
to mostly cloudy conditions.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
Long term period from Friday night into early next week will be
characterized by cool and generally unsettled conditions...

The upper low will be located near the eastern Great Lakes to start
the forecast period, and will eventually move overhead this weekend
before potentially moving off to our east at some point early next
week. There is decent agreement from deterministic and ensemble
guidance that the upper low will be nearby this weekend, but lower
confidence in where it tracks early next week and how quickly/slowly
it departs our region.

With the upper low and cold pool aloft nearby, each day will feature
chances for showers and possibly a few rumbles of thunder. Most
likely timing for showers/storms will be from late morning through
early evening, with diminishing chances for showers each night with
the loss of daytime heating. This will be one of those stretches
where there will be chances for showers at any time, but it will not
be raining all the time. At this point, precipitation looks to
remain showery in nature and not overly heavy, so the threat for any
hydro issues appears to be low. With mainly cloudy skies, afternoon
showers, and a cool airmass overhead, daytime highs will be mainly
in the 60s to 70s each day with overnight lows generally in the 50s
each night. Once the upper low moves off to our east sometime in the
early to middle part of next week, we should see a trend towards
warmer and drier conditions.

&&

.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
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Through 00z Thursday...VFR conditions are expected to prevail
through the 24 hour TAF period, with SCT-BKN mid and/or high
level clouds passing through. There is a low probability of
patchy fog tonight if there are overlapping conditions of clear
enough skies and light enough winds for at least a few hours,
but potential is too low to mention in TAFs at this time. Will
monitor trends for the next issuance.

Winds will initially be southerly around 5 kt, becoming less
than 5 kt overnight. Winds on Wednesday will be south-southwest
around 5-10 kt.

Outlook...

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

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

&&

$$

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