Tornado Warning 20, NWS Binghamton, NY

Area Forecast Discussion
National Weather Service Binghamton NY
248 PM EDT Tue Sep 1 2026

.WHAT HAS CHANGED...
Storm potential has decreased for the rest of today, though it is
still at least somewhat present from Twin Tiers southward.
However, concern has further increased for late Wednesday
afternoon through evening for both severe and excessive rainfall
potential.

&&

.KEY MESSAGES...
1) Corridor of severe thunderstorm risk straddles the area today
and Wednesday, with uncertainty on timing details, yet presses
southward with time into Thursday.

2) A risk for locally heavy rainfall exists, with isolated flash
flood possible. Primary focus of concern is late Wednesday through
Wednesday night for Central NY into the Twin Tiers.

3) A seasonably cooler and mainly dry pattern is anticipated
for the extended Labor Day Holiday Weekend.

&&

.DISCUSSION...
KEY MESSAGE 1...
There remains a severe thunderstorm risk this afternoon-
evening, and even with a potential wave of convection Wednesday
morning. However, the bigger timeframe of concern has shifted
to primarily late Wednesday afternoon into evening.

A wave of non-severe thunderstorms passed through the region
this morning with locally heavy rainfall, extending from the
greater Ithaca and Binghamton NY areas into Susquehanna-Wayne
Counties PA. Despite the shallow warm frontal regime that has
set up straddling our region, we are between waves aloft and
have a lack of a trigger. We will continue to monitor for
a diurnal-heating forced convective cells that could still
manage to pop up in Northeast PA but overall the severe
thunderstorm risk has somewhat scaled back as shear values have
decreased. Whatever we do still get from heating will wane
quickly this evening for a fairly quiet night with patchy fog.

The frontal zone will become even more pronounced Wednesday.
Upper flow will steadily increase through the day, with a couple
waves passing through to interact with the temperature gradient
zone. Precipitable water values, after stepping back a bit
overnight, will ramp back up a bit with a lead shortwave in the
morning and then top off approaching 2 inches with a stronger
wave by Wednesday evening. Undercutting these waves aloft, will
be the light southeast flow encroaching at the surface,
advancing around high pressure over New England to push in some
marine layer. So there will indeed be a gradient of conditions
for the area, with highs ranging form only upper 60s-lower 70s
Poconos-Catskills to lower-mid 80s in Finger Lakes.

With the lead shortwave, there is considerable uncertainty for
whether it will generate and sustain a line of convection/for
how long. Some convection allowing models (CAMS) allow it to
bring a decaying line of convection into the region during the
morning. It will be driven by aloft-processes instead of being
surface-based, so the severe risk may be limited. However, on
the mesoscale we will have to see if it generates renewed
convection with boundaries on the way out, which could lead to
isolated strong to severe.

Wednesday afternoon, convective available potential energy
(CAPE) climbs in a warm and very humid environment. As with
today, there may be a lack of triggers between waves. However,
this time a stronger wave in projected to enter the area late
afternoon through evening which will harness whatever CAPE
builds up before then. Convective parameters especially more
comfortably on the warm side of the frontal zone appear quite
concerning late Wednesday. Surface-rooted storms that fire with
the wave will then ride up the shallow warm front, with time
becoming more elevated. However, shallow warm fronts can be
quite problematic with the shear that the generate in the low
levels. There will be an overlapping zone of elevated helicity,
which is why isolated tornadoes cannot be ruled out in addition
the downburst potential from storm cores. Mitigating factors are
limited midlevel temperature lapse rates as thermal profiles
approach moist-adiabatic, and the trend towards a later arrival
of the wave which is less able to harness diurnal heating.

Though the parade-route of passing shortwaves gradually presses
south into Thursday, it is still close enough to pose a threat
for stronger thunderstorms at least in Northeast PA, and
elevated showers-embedded thunder farther north across the rest
of the region.

KEY MESSAGE 2...

With a stalled front and high precipitable water values
Wednesday into Thursday morning of around 2 inches, potential
for locally heavy rain and at least isolated flash flooding is
a concern. Though there will be a gradient of severe weather
parameters that lessens east of I-81, the parameters for
excessive rainfall will exist well north and east of the frontal
zone in addition to along it. Warm cloud depths will be quite
high, above 12kft agl, and a very moist low level jet will keep
feeding in moisture. The High-Resolution Ensemble Forecast
(HREF) model suite probability matched mean continues to depict
stripes of 2-3 inches. Even though exact locations could
change, there in increasing confidence in the scenario leading
to excessive rainfall amounts somewhere within our general
area. Conjunction of parameters puts more of the focus on
Central NY to Northern Tier of PA versus points farther south.
Timing of waves, and frontal zone location at those times, will
be key for who ends up with flash flooding, with potential for
isolated amounts above 3 inches.

KEY MESSAGE 3...

After the busier pattern through Thursday, the extended Labor
Day Weekend actually looks pretty benign. Friday into early
next week, the large ridge in the central US retrogrades west
with the trough in the northeast nudging into the mid Atlantic.
This will help the flow become more northerly with seasonably
cooler and drier air advecting in. Depending on how cool the
850mb temperatures are, there could be some lake effect rain
showers to deal with at times but for the most part the weekend
into early next week is looking mostly dry. We will be back to
fresh nights with lows of upper 40s-mid 50s, and highs of
mainly 70s.

&&

.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
A mix of VFR and MVFR conditions this afternoon and early
evening within the vicinity of a warm front. TSRA potential
exists given high moisture levels and increasing heating as
ceilings become a bit more broken to scattered. Model guidance
is devoid of much storm development due to lack of a broad
scale trigger, except in the vicinity of KAVP where confidence
is highest late PM and evening. Isolated TSRA possible
elsewhere, but confidence too low. Flight restrictions tank
to IFR tonight within deep shallow moisture. Alternate mins are
possible along with a non-zero chance for airport minimums.
Recovery after 12Z Wednesday will be slow but expect MVFR-IFR
threshold by end of period. Rounds of low confidence convective
activity are being hinted at within model guidance for
Wednesday, so wouldn't be surprised to see later updates carry
TSRA between 12Z-18Z, but confidence is a long shot right now.

Outlook...

Wednesday night through Thursday...Occasional SHRA/TSRA with
associated restrictions.

Friday through Sunday...Low operational impact. Chance of early AM
fog each day. Chance of showers Saturday.

&&

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

&&

DISCUSSION...MDP
AVIATION...JAB

Hazardous Weather Outlook
National Weather Service Binghamton NY
435 PM EDT Tue Sep 1 2026

NYZ009-036-037-045-046-057-022045-
Northern Oneida-Madison-Southern Oneida-Chenango-Otsego-Delaware-
435 PM EDT Tue Sep 1 2026

This Hazardous Weather Outlook is for central New York.

.DAY ONE...Tonight.

Hazardous weather is not expected at this time.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday.

Locally heavy rain will be possible from thunderstorms late
Wednesday through Wednesday night, which could lead flash flooding
for some locations. A few of the storms could also be strong to
severe with gusty winds and perhaps hail.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be needed. Please relay any information about
severe weather to the NWS.

NYZ062-022045-
Sullivan-
435 PM EDT Tue Sep 1 2026

...SEVERE THUNDERSTORM WATCH 638 IN EFFECT UNTIL MIDNIGHT EDT
TONIGHT...

This Hazardous Weather Outlook is for central New York.

.DAY ONE...Tonight.

Please listen to NOAA Weather Radio or go to weather.gov on the
Internet for more information about the following hazards.

   Severe Thunderstorm Watch.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday.

Locally heavy rain will be possible from thunderstorms late
Wednesday through Wednesday night, which could lead flash flooding
for some locations. A few of the storms could also be strong to
severe with gusty winds and perhaps hail.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be needed. Please relay any information about
severe weather to the NWS.

PAZ038>040-043-044-047-048-072-022045-
Bradford-Susquehanna-Northern Wayne-Wyoming-Lackawanna-Luzerne-Pike-
Southern Wayne-
435 PM EDT Tue Sep 1 2026

...SEVERE THUNDERSTORM WATCH 638 IN EFFECT UNTIL MIDNIGHT EDT
TONIGHT...

This Hazardous Weather Outlook is for northeast Pennsylvania.

.DAY ONE...Tonight.

Please listen to NOAA Weather Radio or go to weather.gov on the
Internet for more information about the following hazards.

   Severe Thunderstorm Watch.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday.

Isolated to scattered severe thunderstorms are possible Wednesday
through Wednesday night, especially along and west of I-81. Main
threats are damaging winds, hail, and locally heavy rainfall.
However, an isolated tornado cannot be ruled out. A small risk of
strong to severe thunderstorms could linger into Thursday but will be
shifting south with time.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be needed. Please relay any information about
severe weather to the NWS.

NYZ015>018-022>025-044-055-056-022045-
Yates-Seneca-Southern Cayuga-Onondaga-Steuben-Schuyler-Chemung-
Tompkins-Cortland-Tioga-Broome-
435 PM EDT Tue Sep 1 2026

This Hazardous Weather Outlook is for central New York.

.DAY ONE...Tonight.

Hazardous weather is not expected at this time.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday.

Isolated to scattered severe thunderstorms are possible Wednesday
through Wednesday night, especially along and west of I-81. Main
threats are damaging winds, hail, and locally heavy rainfall which
could lead to isolated flash flooding. However, an isolated tornado
cannot be ruled out.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be needed. Please relay any information about
severe weather to the NWS.