-- Discussion containing changed information from previous version are highlighted. --
312
FXUS61 KALY 250541
AFDALY

AREA FORECAST DISCUSSION
National Weather Service Albany NY
141 AM EDT Tue Jun 25 2024

.SYNOPSIS...
High pressure builds in this morning with
decreasing clouds and cool conditions. High pressure will allow for
dry and sunny weather on during the afternoon , with comfortable
levels of humidity. Warm and more humid conditions are expected on
Wednesday afternoon into Wednesday night, along with some afternoon
and evening thunderstorms.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
.UPDATE...As of 129 AM EDT...High pressure will be building in
from eastern Great Lakes Region over NY and New England this
morning. The winds continue to go light to calm, as the skies
have become clear to mostly clear. Some radiational cooling is
likely with lows in the 50s to lower 60s with isolated upper 40s
over the southern Dacks. We added slightly more patchy
radiational mist/fog over the CT River Valley, Berkshires and
the Upper Hudson River Valley and Lake George Region.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH WEDNESDAY NIGHT/...
High pressure will continue to allow for quiet weather through
the day on Tuesday. Behind the departing upper level trough,
heights and temps aloft will be rapidly rising on Tuesday. 850
hpa temps will reach +16 C by late Tuesday. Valley areas will be
up into the mid to upper 80s for highs, with upper 70s to low
80s in the high terrain. Despite the warm temps, dewpoints will
remain comfortable in the 50s thanks to the deep mixing and the
low level flow out of the west. Skies will be fairly sunny
through the day, but some clouds will start to increase for late
in the day.

On Tuesday night, temps will milder than Monday night, with lows
in the 60s. Some passing clouds are expected and maybe a few
light showers across northwestern areas as warm front starts
approaching from the west.

Our area will be within a warm sector for Wednesday. Upper level
shortwave trough will be moving from the Great Lakes towards the
Northeast on Wednesday with a surface cold front approaching
from the west and some showers and thunderstorms look to develop
across the area. With a warm and more humid air mass in place,
there should be some instability to work with across the region.
12z NAM suggest SBCAPE values may exceed around 1000 J/kg on
Wednesday. Decent deep-layer shear looks to be in place as well,
so any storms that develop could become organized. SPC has a
marginal to slight risk across the region, with the best threat
for organized storms across southern areas, where there will be
the best overlap of instability, shear and storm coverage. These
storms could linger into Wed night as well depending on the
exact timing of the cold front.

Temps will be rather warm again on Wednesday with highs well
into the 80s to low 90s. With dewpoints creeping higher, heat
index values could approach advisory criteria in the mid Hudson
Valley. Temps should fall into the mid 50s to mid 60s behind the
front on Wednesday night, with some clearing expected late.

&&

.LONG TERM /THURSDAY THROUGH MONDAY/...
The long term period will begin with the 500 hPa trough axis
shifting east and high pressure building into the Northeast
behind a surface cold front. This will contribute to dry
conditions and seasonable temperatures on Thursday and Friday.

Ensemble guidance is in relatively good agreement with the
evolution of a shortwave trough at 500 hPa that will progress
eastward across the Great Lakes and Northeast on Saturday and
Sunday. A warm front with the associated surface low is forecast
to lift northeast through the CWA Saturday morning. Low level
flow within the warm sector of the surface cyclone will advect
tropical moisture into the CWA with NAEFS/ENS mean PWAT
increasing to over 1.75" by Saturday evening (above the 90th
percentile of KALB sounding climatology for late June/early
July). The abundant moisture will support medium to high
(50%-80%) chances for precipitation late Saturday afternoon
through Sunday morning as the trough and surface cyclone move
east of the forecast area. Based on the progressive nature of
the system, the likelihood of flash flooding is currently very
low (5% chance or less) despite the abundant moisture being
advected into the region. While vertical wind shear greater than
30 knots will be supportive of organized convection, there is
uncertainty with regards to how much destabilization will be
able to occur within the warm sector of the surface cyclone.
Therefore, the likelihood of strong/severe thunderstorms
currently looks to be low (less than 15%). The system is
expected to exit the area Sunday evening with drier conditions
expected early next week.

&&

.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
-- Changed Discussion --
IFR visibility with even periods of LIFR visibility will be
maintained at GFL through 11 UTC/25 due to fog formation under
radiational cooling conditons while ALB/POU remain VFR. We
removed the mention of fog development at PSF given current dew
point depression at over 5 degrees; however, ongoing radiational
cooling conditions will support additional cooling and as
temperatures at PSF cool into the mid-50s towards sunrise, some
patchy fog may form. Given how early sunrise is in late June,
did not have enough confidence to include MVFR visibility at
PSF, especially given lack of support in forecast soundings.
Will continue to monitor and adjust visibility forecast as
needed.

Early fog at GFL burns off by or shortly after 11 UTC. Then SKC
conditions expected at all terminals thanks to large scale
subsidence building in behind our departing upper level trough.
Cirrus clouds return after 00 UTC from west to east at all terminals
before mid-level clouds with ceilings around 10kft return. A few
isolated showers may approach ALB, POU, and GFL by or shortly after
03 UTC with the potential reaching PSF towards the end of the TAF
period. Given plenty of dry air beneath the cloud deck, maintained
VFR conditions as any light showers or sprinkles that arrive prior
to 06 UTC will likely not result in a flight category degradation.

Light and variable winds through 12 UTC. Then winds shift out of the
west or southwest by 14-16 UTC at all terminals and turn a bit
breezy becoming sustained 5-9kts and gusts reaching up to 15kts.
Strongest winds at ALB and PSF. Then, winds likely become light and
variable by 01 - 03 UTC at all terminals.

Outlook...

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

&&

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

&&

$$

SYNOPSIS...Frugis/Wasula
NEAR TERM...Wasula
SHORT TERM...Frugis
LONG TERM...Humphrey
AVIATION...Speciale