Severe Thunderstorm Warning 71, NWS Binghamton, NY

Area Forecast Discussion
National Weather Service Binghamton NY
741 PM EDT Thu Jun 19 2025

.SYNOPSIS...
Scattered rain showers and thunderstorms across the area this
afternoon, with a cold front this evening bringing more
widespread storm chances. Temperatures fall back to seasonable
across the area for Friday with some scattered showers and
storms possible. A very strong high pressure system will build
into the area this weekend through mid week, bringing extremely
hot temperatures Sunday into the middle of the week.

A surface trough will move through the afternoon hours, bringing a
chance for isolated to scattered severe thunderstorms possible.
Conditions stay warm and humid today before being followed by a
brief cool down to finish out the week. Temperatures then surge
much warm early next week. There will be chances for showers
and thunderstorms through the weekend followed by a few dry days
to start next week.

&&

.NEAR TERM /THROUGH FRIDAY NIGHT/...
4 PM Update...

Major overhaul to the forecast for this afternoon and evening.
Severe thunderstorms now appear unlikely, as the greatest
instability will be south and east of our CWA. Cold front will
still push through the region this evening with a line of
showers and an embedded isolated thunderstorm. The severe threat
with this line will be low, but this line could produce some
localized gusty winds up to 40 to possibly as high as 45 mph,
Also, significantly lowered PoPs until this line comes in later
this evening with only isolated shower or thunderstorm until
then. Although the threat for an isolated severe segment along
this line is not completely non-existent, in certainly does not
warrant a Severe Thunderstorm Watch, so that has been canceled
and the enhanced wording for damaging winds has been removed
from the forecast as well.

200 PM Update...

Isolated showers and storms have developed across areas east and
southeast of the Finger Lakes. A few thunderstorms have
developed over Sullivan county, but the rest of the convection
has not produced lighting yet. The environment is uncapped at
the surface, but morning clouds have really limited CAPE values
and low level lapse rates west of I-81. Mid-level dry air is
also present, which is another factor causing storm initiation
to fail. This can be seen in radar as most cells moving into
this area are dissipating pretty quickly. The best chance for
thunderstorms and severe weather this afternoon remains east of
I-81, especially in the Catskills and Poconos, where CAPE is in
the 1500-2000j/kg range and 0-6 bulk shear is 30-35kts. Storms
are moving pretty quickly to the NE as a strong low pressure
system over Ontario is driving strong winds out of the SW.
Surface winds will be strong this afternoon and evening with
sustained winds of 10-15kts, gusting up to 30kts. Also with the
fast storm motion, flash flooding is not expected at least into
the late afternoon hours.

Based on the latest CAM guidance and radar trends, it
looks like the majority of the thunderstorms that will impact
the CWA will develop along a cold front that will move into the
western Finger Lakes around 5pm. This should move from west to
east through the evening, exiting to the east by 11pm. Gusty to
isolated damaging winds will be the main threat with these
storms, along with hail and a very small chance for a brief,
weak tornado. Storm strength and activity should weaken as the
front approaches I-81. By this time, instability will be low as
we will have lost daytime heating and rain and storms this
afternoon may work over the area, helping to limit storm
development. Winds will remain strong behind the front, with
10-15kts gusting to 25kts out of the west through Friday.

The upper level trough axis looks to swing through the area
tonight, kicking off some scattered rain showers north of the
Southern Tier. Temps and dewpoints will provide much nicer
sleeping weather, with temps in the mid to upper 50s and
dewpoints in the mid 50s.

Friday is expected to be pleasant, with highs in the mid 70s to
low 80s and much less humidity. A weak shortwave may pass
through in the afternoon, kicking off isolated showers and
thunderstorms over the Finger Lakes into the Twin Tiers. Another
shortwave will ride the edge of a strong ridge that will build
into the area this weekend. Scattered rain showers with some
isolated rumbles of thunder moving from NW to SE will be
possible.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
100 PM Update

Will be watching shower and thunderstorm potential in this period,
along with developing hot and humid conditions by Sunday.

Saturday features rising heights aloft as an upper level ridge
begins to build over the region. A strong shortwave disturbance is
modeled to ride over the top of the ridge heading into Saturday
night and Sunday morning. Therefore, most of Saturday looks dry with
just an isolated late day pop up t'storm possible across Central NY.
It will be partly sunny, a bit more humid and warm with highs in the
80s areawide. As the above mentioned shortwave rolls across southern
Canada Saturday night, a strong warm front will push through at the
surface for our area. Mixed layer instability increases markedly
overnight as a strong Elevated Mixed Layer (EML) arrives; mid level
lapse rates approach or perhaps exceed 8.0C/Km with the northwest
flow over the top of the building ridge. This is a classic setup for
fast moving complexes of thunderstorms, so this will be something to
watch closely (especially CNY) Saturday night into Sunday morning.
By Sunday afternoon any lingering morning convection or clouds
dissipate...giving way to sunshine, high humidity and hot
temperatures. Latest model data is trending up with temperatures and
heat indices for Sunday. 13z NBM now shows highs ranging from the
upper 80s to mid-90s Sunday afternoon, with dew points 70-75...this
gives peak heat indices in the low 90s to low 100s. This upward
trend is likely due to the 500mb ridge building in faster, with
heights reaching 595dm by early evening. Upper level high moves
directly overhead Sunday night, giving clear skies, light winds and
muggy conditions with lows in the upper 60s to low 70s.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
100 PM Update

Main story in this period will be the extremely hot and humid
conditions, with possible record high temperatures earl in the week.
Very warm to hot conditions continue midweek, with increasing shower
and thunderstorm potential.

Latest guidance, including the 13z NBM continues to trend higher
with the temperatures Monday and Tuesday. Our official forecast
follows this trend, and is even on the lower side of guidance near
the 25th percentile NBM. The deterministic NBM may be suffering
feedback from climatology and/or previous forecast, considering it
is now below the 10th percentile on Monday. Did not want to go too
much higher, but again, went close to the 25th percentile NBM which
put Monday in the top 5 of observed all time high temperatures in
June at many of our Climate data sites. This matches up well with
the ECMWF extreme forecast index, which is in the 95-99th percentile
across most of the area. 850mb temperatures around 20-21C also
support highs well into the 90s both Monday and Tuesday afternoon.
It's possible a few of the deeper valley locations may even hit 100
degrees. Also factoring in surface dew points in the upper 60s to
lower 70s during the afternoon, and peak heat indices will be
downright oppressive between the upper 90s to low 100s both days.
Monday will be rain free and sunny under the extensive upper ridge,
while Tuesday could see a stray pop up late day thunderstorms as the
upper high shifts slightly south. Overnight lows only dip into the
70s. These hot daytime and muggy nighttime temperatures will lead to
major/locally extreme HeatRisk over the region. As confidence
continues to increase Extreme Heat Watches may eventually be needed.

The center of the upper level ridge/high drops south Wednesday into
Thursday. This will open the door for showers and thunderstorms to
move through our area on the norther periphery of this feature.
Temperatures gradually decrease, but it will still be very warm to
hot on Wednesday with mid-80s to low 90s expected, with generally
80s expected for highs by next Thursday.

&&

.AVIATION /00Z FRIDAY THROUGH TUESDAY/...

Line of showers and thunderstorms still need to make their way
through BGM and AVP this evening and may bring brief
restrictions. Behind the cold front, an MVFR cloud deck is
expected to move across the region as an upper level trough
axis pushes through. All sites are expected to see MVFR
ceilings for most of the night, which should scatter out during
the morning hours.

Outlook...

Friday night through Saturday... Isolated showers and
thunderstorms possible with associated restrictions.

Saturday night...Overnight thunderstorms possible, especially
over NY with associated restrictions.

Sunday thru Tuesday...High pressure with VFR expected.

&&

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

&&

SYNOPSIS...JTC
NEAR TERM...JTC/MPK
SHORT TERM...MJM
LONG TERM...MJM
AVIATION...JTC/MPK

Hazardous Weather Outlook
National Weather Service Binghamton NY
403 PM EDT Thu Jun 19 2025

NYZ009-015>018-022>025-036-037-044>046-055>057-062-PAZ038>040-043-
044-047-048-072-202015-
Northern Oneida-Yates-Seneca-Southern Cayuga-Onondaga-Steuben-
Schuyler-Chemung-Tompkins-Madison-Southern Oneida-Cortland-Chenango-
Otsego-Tioga-Broome-Delaware-Sullivan-Bradford-Susquehanna-
Northern Wayne-Wyoming-Lackawanna-Luzerne-Pike-Southern Wayne-
403 PM EDT Thu Jun 19 2025

This Hazardous Weather Outlook is for central New York and
northeast Pennsylvania.

.DAY ONE...Tonight.

A cold front will move through the area late this afternoon and
evening. There will be a chance for scattered showers and embedded
isolated thunderstorms. The potential for severe storms is low, but a
few strong wind gusts could occur with the passing line. Localized
flash flooding could also occur.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday.

There is increasing confidence for oppressive heat and humidity
starting Sunday through at least Tuesday. Heat index values in the
upper 90s to low 100s are forecast with little relief at night due
to elevated humidity. Monitor the forecast for details in coming
days on this potential for a significant heat wave.

.SPOTTER INFORMATION STATEMENT...

Weather spotters are encouraged to report significant weather
conditions according to Standard Operating Procedures. Please relay
any information about severe weather to the NWS.

Special Weather Statement
National Weather Service Binghamton NY
458 PM EDT Thu Jun 19 2025

NYZ009-015>018-022>025-036-037-044>046-055>057-062-PAZ038>040-043-
044-047-048-072-200200-
Northern Oneida-Yates-Seneca-Southern Cayuga-Onondaga-Steuben-
Schuyler-Chemung-Tompkins-Madison-Southern Oneida-Cortland-
Chenango-Otsego-Tioga-Broome-Delaware-Sullivan-Bradford-
Susquehanna-Northern Wayne-Wyoming-Lackawanna-Luzerne-Pike-
Southern Wayne-
458 PM EDT Thu Jun 19 2025

...LINE OF SHOWERS AND THUNDERSTORMS WILL MOVE ACROSS CENTRAL NY
AND NORTHEAST PA THIS EVENING...

A line of showers and thunderstorms will push eastward across the
region this evening. Although it is unlikely that these storms
will be severe, a few storms may be capable of producing brief
heavy rainfall and gusty winds up to 45 mph. A quick half inch to
an inch of rain is possible in 30 to 60 minutes with these storms.
This could lead to some isolated instances of urban and or poor
drainage flooding, especially in areas that are already saturated.
Please be mindful of the potential for rapidly changing weather
conditions, especially if outdoors this evening.

Listen to NOAA Weather Radio,or your local media for the latest
updates on this situation.

Sera/Kistner

Preliminary Local Storm Report
National Weather Service Binghamton NY
842 PM EDT Thu Jun 19 2025

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0808 PM     Tstm Wnd Dmg     Meshoppen               41.62N 76.04W
06/19/2025                   Wyoming            PA   911 Call Center

            Tree down across Allen Street.

&&