767
FXUS61 KALY 220704
AFDALY

Area Forecast Discussion
National Weather Service Albany NY
304 AM EDT Mon Jun 22 2026

.WHAT HAS CHANGED...
Max temps were lowered this afternoon below the NBM values by
3-4 degrees with the rain cooled air due to the approaching
wave and warm front.

Moderate to heavy rainfall from the warm front and the wave
continues to be this afternoon and prior to midnight with
hourly rainfall up to or around an inch an hour possible, and
the consensus to a slightly more northern track continues.

Some showers may linger Tue morning across western New England
and from the Capital District south and east with the mid and
upper deformation zone to the wave.  In the wake of the system
Tue, some patchy valley fog was added mainly north of the
Capital Region.

&&

.KEY MESSAGES...
1) High confidence for a widespread soaking rainfall across
eastern NY/western New England today into tonight. This will be
a largely beneficial rainfall for most areas, although isolated
minor flooding in urban/poor drainage areas is possible.

2) After a dry mid week, temps rise slightly above normal with
increasing humidity levels with chances of showers and
thunderstorms increasing late Thu through Fri.

&&

.DISCUSSION...
KEY MESSAGE 1...
Low pressure approaches from the Ohio Valley and the Lower Great
lakes Region this morning. A closed H500 low is moving across
southeast Ontario into Quebec. The sfc low and its warm front
will cause clouds to thicken and lower this morning, as morning
valley mist/fog in the Lake George/Glens Falls area, southern VT
valleys and Berkshires burns off. The low-level jet will
increase ahead of the warm front with PWATS rising into the
1.25-1.75" range across the forecast area with the highest
values around 1.75" south and east of the Capital District.
These PWATS are 1-2 STDEVs above normal according the latest
NAEFS. Isentropic lift increases ahead of the warm front and
approaching cyclone with favorable mid and upper level jet
dynamics /right entrance region of the jet/ in tandem with
strong FGEN in the 850-700 hPa layer moving over central-
eastern NY and western New England in the afternoon into the
early evening 18Z-00Z/Tue timeframe. Strong moisture advection
occurs with periods of moderate to locally heavy rain to occur.
The latest HREFs indicate mean MUCAPEs of 100-250 J/kg from the
Capital Region, southern VT and northern Catskills southward
this afternoon into early tonight. Some pockets in the 250-500
J/kg range are closer to I-84. The 0-6 km shear increases to
35-50 KT towards 00Z/Tue, but with elevated parcels and limited
instability the severe threat seems low due to limited
instability, though the wave moving a but further north like the
NAM, 3-km HRRR and CMC might allow the mid Hudson Valley to get
into a warm sector briefly. SPC continues a Marginal Risk
(Level 1 of 5) for the southern 3 counties
(Ulster...Dutchess...and Litchfield Counties) with damaging
winds the main threat. We did include slight to low chances of
thunderstorms as far north as the Mohawk Valley, Capital
District and southern VT.

The biggest impact with this system would be the rainfall and
enhanced rainfall rates, which are supported by the 3-km HRRR.
Some hourly rates could reach or slightly exceed an inch per
hour. The 3-km HRRR shows high probs of 0.25-0.50"/hr as far
north as the Capital District and southern VT. The latest NBM
indicates probabilities of 60-90% that 24-hr rainfall amounts
could exceed one inch by 12Z/8 am Tue for most of the forecast
area, except for the southern Dacks. In fact the maximum probs
have shifted north over the Capital Region and southern VT. The
probabilities for >2" are 20-50%. Our forecast supported the
latest NBM/WPC forecast with 1-1.50" of rainfall for the event
with some 1.50-2.0" amounts over the southern VT and the
southern Taconics, Berkshires and NW CT. Expect a half an inch
to an inch over the southern Dacks. The amounts will vary where
the heavier showers and thunderstorms set up and some localized
amounts of 2-3" are possible.

The Marginal Risk continues over most of the forecast area,
except the southwest Adirondacks. An isolated flash flood can
not be ruled out if rainfall rates becomes excessive or storms
train or back build briefly. Ponding of water and poor drainage
flooding is likely. The rainfall will be beneficial, as many
areas along and south of I-90 are in D0 (Abnormally Dry) to D1
(Moderate Drought) based on the latest Drought monitor. The
rainfall eases up after midnight, but lingers south and east of
the Capital Region into western New England into mid to late
Tue morning with residual mid and upper deformation support.
Temps this afternoon will run cooler than normal with the clouds
and rain cooled air with highs only in the 60s to lower 70s
with some. We went below the NBM guidance by 3-4 degrees and
closer to a MAV/MET blend. In the wake of the system, lows fall
back into the 50s to lower 60s.

KEY MESSAGE 2...
High pressure builds in late Tue through Wed. Temps will remain
seasonable for the mid week. Some patchy to areas of fog may
form in some of the major valleys Tue night especially north of
the Capital District. Temps trend near normal on Wed with 70s to
lower 80s (some upper 60s over the higher terrain) with
comfortable humidity levels.

The timing varies on the next system for Thu into Fri, as a
short-wave and a low pressure system approaches from the Great
Lakes Region and southeast Ontario for Thu. The better chance
for showers and thunderstorms on Thu will be from the Hudson
River Valley westward. Chances of showers and thunderstorms
increase Thu night into Fri ahead of the wave and cold front. We
will continue to monitor if any thunderstorms will be on the
strong side by Friday with dewpoints rising into the mid and
upper 60s and increasing humidity levels. The degree/amount of
instability remains uncertain late in the week. Temps Thu and
Fri will be range from the 70s to lower/mid 80s which are
slightly above normal for early summer for eastern NY and
western New England.

&&

.AVIATION /06Z MONDAY THROUGH FRIDAY/...
Through 06Z Tuesday... MVFR/IFR radiational mist/fog will
likely continue at KGFL prior to 09Z-10Z before thicker cirrus
begins to move in. A TEMPO was used between 06Z-09Z/Mon for KPSF
for a brief window of IFR radiational mist/fog too. Mid and
high clouds quickly move in between 09Z-15Z/Mon at the TAF
sites. Clouds gradually lower across all terminals prior to
15Z/MON. Initial batch of light rain/showers moves in between
15Z-18Z/MON with VFR cigs/vsbys lowering to high MVFR levels
between 18Z-20Z/MON and spotty IFR levels. The rain becomes
steadier and heavier after 20Z/Mon and widespread low MVFR/IFR
conditions will impact all the TAF sites. A thunderstorm with a
TEMPO group was added to KPOU between 20Z/Mon and 00Z/Tue. It
may have to be extended past 00Z/Tue with later TAF issuances.
Our confidence was lower for thunderstorms further northward and
we left out of the TAFs for now at KALB/KPSF/KPSF. Widespread
IFR and even some LIFR conditions in terms of cigs may develop
after 00Z/Tue in the deep moisture as the wave approaches
southern NY and passes to the south and east overnight.
Occasional showers continue until the end of the TAF cycle.

Calm to light and variable winds 4 KT or less across all
terminals prior to 12Z/Mon. Southeast to southerly winds in the
5-10 KT range increase in the late morning. The winds become
northeast in the afternoon into the evening at less than 10 KT
at KALB/KGFL with southeast to east winds at KPSF/KPOU at 4-8
KT. Low-level wind shear was added for KPOU/KPSF after 00Z/Tue,
where winds at 2 kft AGL increase to 35-40 KT, and the sfc winds
are less than 10 KT.

Outlook...

Tuesday Night: No Operational Impact. NO SIG WX.
Wednesday: No Operational Impact. NO SIG WX.
Wednesday Night: No Operational Impact. NO SIG WX.
Thursday: Moderate Operational Impact. Chance of SHRA...TSRA.
Thursday Night: High Operational Impact. Definite SHRA...TSRA.
Friday: High Operational Impact. Likely SHRA...TSRA.

&&

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

&&

$$

DISCUSSION...15
AVIATION...31/15