630
FXUS61 KBGM 171748
AFDBGM

Area Forecast Discussion
National Weather Service Binghamton NY
148 PM EDT Tue Jun 17 2025

.SYNOPSIS...
Cloudy and somewhat cool weather continues today, along with
scattered showers, as well as areas of fog or drizzle in the
higher terrain. Warmer weather comes Wednesday into Thursday,
providing more energy for showers and thunderstorms especially
in the afternoons. After temperatures temporarily settle back
Friday, they will surge much warmer into early next week.

&&

.NEAR TERM /THROUGH WEDNESDAY NIGHT/...
655 AM Update...
Fog did develop overnight in the higher terrain of Northeast PA
into the Catskills. It will be very gradual to thin that out as
south-southeast low level flow persists.

Previous discussion...
Things will remain fairly steady state today through tonight,
with clouds and scattered showers, but somewhat better thunder
chances wait for Wednesday which will be warmer and more humid.

We continue to hold a moist stable south-southeast low level
flow near the surface, and a west-southwest flow aloft with
embedded shortwaves. Thunder will not be much of a thing today
given the cool conditions of the lowest few thousand feet, but
shortwaves aloft may introduce minor elevated instability for
isolated thunder to accompany the likely waves of showers this
afternoon into evening, including with the eventual warm front
tonight. The more surface-based activity well to our southwest
in the advancing warm sector of the system, will have more
potential for locally heavy rain, but not expecting that to be
an issue this far north yet.

Downsloping wind as well as relatively less shower activity
will help the northern Finger Lakes and NY Thruway corridor
reach mid-upper 70s today; elsewhere thicker clouds, scattered
showers, and even some higher elevation fog/drizzle will hold
highs to only upper 60s-lower 70s for most locations. Then as
the warm front arrives tonight, higher dewpoints will lead to a
humid warmer night with lows in the 60s and continued scattered
showers. Areas of fog will probably persist for the Poconos-
Catskills areas.

The warm sector of the system will be over us on Wednesday,
boosting temperatures into the upper 70s-mid 80s. Even more
noticeably, dewpoints will rise to humid levels in the upper
60s-lower 70s. There will not be much in terms of surface
features, but a shortwave or two embedded within southwesterly
flow aloft should be able to harness the increased instability
to generate some showers and thunderstorms. That said, there
will be quite a bit of cloud cover to limit heating. Shear will
be modest; generally under 30 knots. Convective Available
Potential Energy will also tend to be tall and narrow as model
soundings take on more of a moist-adiabatic look. Precipitable
Water values reach 1.6-1.9 inches. Thus despite decent chance of
thunder especially towards Wyoming Valley-Poconos-Catskills,
potential for strong cells appears rather low. Anytime you have
high precipitable water, locally heavy rainfall will need to be
considered, but nothing too organized on that is apparent at
this time.

We enter a void between exiting shortwave and approaching front
Wednesday night, so shower/thunder activity will generally go
into a lull, with humid conditions and lows of mid 60s-near 70.

&&

.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
400 AM Update...
Main concern is the potential for severe thunderstorms Thursday
afternoon. The Storm Prediction Center places our area in a
Marginal to Slight Risk of Severe Thunderstorms, with potential
somewhat favoring Northeast PA and areas along/east of I-81 in
NY versus points west.

Models continue to differ on how things evolve Thursday. ECMWF
model and at least to some degree the NAM model, bring a deeper low
pressure across southern Ontario and into Quebec, with a
strongly-forced trailing front progressing fairly quickly
through our region. The GFS meanwhile is weaker with its low,
and thus with less forcing, is slower with the front. ECMWF-NAM
scenario might send the front through too quickly to generate
strong to severe storms for much of our area, though Wyoming
Valley-Poconos-Catskills areas would have the somewhat better
chance of still having enough time to harness new diurnal
instability. GFS timing is more ideal for capturing all of
daytime heating and more of the area.

The severe thunderstorm potential will be dependent of the
timing of the front. The National Blend of Models paints a 50-80
percent probability for surface-based Convective Available
Potential Energy (CAPE) to reach above 1500 J/kg in the central
to especially southeastern parts of our area where highs are
forecast in the mid-upper 80s. This accompanied with bulk shear
of 35-45 kts would be enough for strong to severe thunderstorms
with damaging winds and perhaps large hail given the portion of
CAPE aloft in the hail growth zone. Add a layer of drier air
advecting in midlevels, and inverted-V in lowest portion of
model soundings, and there is reason to be concern for intense
gusts from storm cores.

The high Precipitable Water values, with Gulf connection, that
will pool ahead of the front is cause for concern of locally
heavy rainfall. Somewhat mitigating that, however, will be speed
of individual cells. However, warm cloud depths exceeding 10 kft
and cloud-layer flow at times nearly negating the low level jet
vector could lead to backbuilding cells somewhere within our
area especially if a more GFS-like scenario pans out; NAM-ECMWF
scenario will tend to push things through. Weather Prediction
Center has placed most of our area in a Marginal Risk - 1 on a
scale of 1 to 4 - for Excessive Rainfall.

Behind the front, temperatures and especially dewpoints will
take a step back. However, a loose upper trough will still be
swinging through the region. With diurnal heating, we can
anticipated isolated to scattered showers to pop up Friday,
especially Twin Tiers northward. Generally dry conditions are
anticipated Friday night, with lows of 50s-near 60.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
425 AM Update...
A ridge will build across the region as we head into early next
week, presenting a potentially significant heat wave. During
the transition, ridge-riding storms could pass through the
region over the weekend.

An anomalously strong heat dome is projected to swell over the
Ohio Valley-Southwestern Great Lakes Saturday, and then build
our direction Sunday-Monday. The belt of westerlies over the top
of the developing high, will contain embedded waves that will
have ample instability aloft that could be harnessed. With time,
convective inhibition/thermal capping will become more of a
limiting factor for thunderstorms as the high noses into our
region. However, Saturday through Saturday night appear ripe for
any mesoscale convective complexes that develop over the top of
the ridge, to potential drop southeast across our area. That of
course, depends on if they can develop upwind. Mesoscale
convective complexes are also not reliant on surface heating, so
they could happen day or night. By Sunday, more inhibition
moves in though there will still be a small chance of
thunderstorms.

There is high confidence for oppressive heat early next week,
Sunday-Tuesday. Forecast highs are well into the 90s throughout
our lower elevations, peaking Monday-Tuesday, with 70-ish
dewpoints that could easily push heat index values around 100
degrees; perhaps higher in some spots. Now is the time to plan
for a consecutive string of hot days and little relief at night.

&&

.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
Mainly MVFR to Fuel Alternate ceilings are expected to remain
for the remainder of today. A round of light to moderate showers
may move through late this afternoon/early this evening, which
may bring brief IFR restrictions. Otherwise, IFR ceilings will
become more prevalent later tonight into early Wednesday
morning, before ceilings return to mainly MVFR by late Wednesday
morning/early afternoon.

Outlook...

Wednesday afternoon through Thursday...Coverage of showers and
thunderstorms increase, especially each afternoon. Occasional
restrictions likely.

Thursday night through Sunday...Mainly VFR, but isolated to
scattered afternoon showers and possibly a thunderstorm may
result in brief restrictions; chances somewhat better for NY
terminals versus KAVP which may stay dry.

&&

.BGM WATCHES/WARNINGS/ADVISORIES...
PA...None.
NY...None.

&&

$$

SYNOPSIS...MDP
NEAR TERM...MDP
SHORT TERM...MDP
LONG TERM...MDP
AVIATION...BJG