Waterloo, New York Weather Forecast Discussion

029
FXUS61 KBGM 211802
AFDBGM
Area Forecast Discussion
National Weather Service Binghamton NY
202 PM EDT Sun Sep 21 2025
.SYNOPSIS...
A much more unsettled and showery weather pattern arrives
Monday afternoon and continues through the upcoming week. A
series of fronts and waves of low pressure will bring clouds
and shower chances each day. Temperatures look to remain mild,
with near to above average readings expected.
&&
.NEAR TERM /THROUGH MONDAY NIGHT/...
Mainly quiet weather continues tonight, with clouds clearing this
evening, then increasing again late at night. South winds will be
slightly breezy, mainly between 7-15 mph with some gusts around 20
mph at times. These partly cloudy and breezy conditions should
likely prevent much, if any fog from forming overnight. Lows will be
milder, in the 40s to low 50s for east-central locations...with mid-
50s to around 60 degrees across the Finger Lakes and Syracuse metro.
Monday starts off with partly to mostly sunny conditions, but clouds
gradually increase from west to east later in the day. As PWATs rise
up near 1.50 inches, shower chances break out for areas west of I-81
and north of Route 17/I-86 by the afternoon hours. There will even
be a chance for a few thunderstorms as mixed layer instability
reaches several hundred J/Kg over the far western portion of the
CWA. Monday will be very warm, with highs in the mid-70s to lower
80s across the area...this is about 10-12F above average for the
first day of fall. Mostly cloudy and showery conditions continue
into Monday night with very mild overnight lows in the mid-50s to
lower 60s.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
This period will feature more unsettled weather, with clouds and
showers around. A surface front will remain in place, bi-secting the
forecast area on Tuesday. A wave of low pressure is forecast to
develop and move northeastward along this boundary, across Central
NY and Northeast PA through the day. This will bring likely to low
end categorical PoPs for on and off periods of rain...and also a
chance for thunderstorms. MLCAPE values should reach around 500 J/Kg
with deep layer (0-6km) shear values up to around 30 kts at times.
This should allow a few scattered thunderstorms, or even clusters of
thunderstorms to develop and track across the CWA in the afternoon
hours. This will be our first good chance for accumulating rainfall
in about 2 weeks. Rainfall amounts remain uncertain, but most likely
will be between a tenth to one-half inch in most locations. PWATs
are actually decreasing through the day, down to around 1.25 inches
as the front slides east. It should be another warm day, with highs
in the mid-70s to lower 80s once again. The front should slowly
press east-southeast heading into Tuesday night, with lingering
showers in the evening gradually tapering off and decreasing in
coverage late at night. Another warm night, with lows in the mid-50s
to lower 60s.
It looks like our region will be under the influence of a mid/upper
level trough on Wednesday with lingering moisture and instability in
the NW flow regime. This may allow for scattered pop up showers and
isolated t`storms to develop in the afternoon...especially from the
Twin Tiers/Catskills south into NE PA. Seasonably mild temperatures
expected in the 70s. Another warm front with additional showers is
progged to start approaching from the south-southwest Wednesday
night; otherwise skies are mostly cloudy with mild overnight lows.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
This period looks to remain unsettled and showery much of the time.
Shower chances are increasing for Thursday as a frontal system
slowly works its way through the region. An upper level trough
remains in place across the Ohio and Tennessee valleys right into
Friday, bringing additional chances for rain to Central NY and
Northeast PA in the moisture southerly flow. Temperatures will still
be mild despite the clouds and showers around; with highs in the
upper 60s to lower 70s and overnight lows in the 50s to near 60.
There is greater uncertainty in the forecast for next weekend. The
NBM and ensemble guidance keeps about a 40-50% chance for more
showers on Saturday, fading to 20-30% chance next Sunday. Overall,
it appears a general broad upper level trough will be working it`s
way through the area, so these shower chances make sense. However,
overall spread in the guidance is greater than usual, so adjustments
or changes to the forecast may be needed in this portion of the
extended as we get closer in time. Temperatures look to remain
steady in the 70s during the day, and upper 40s to 50s overnight.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
VFR is generally expected at most TAF sites through the period.
Diurnal clouds between FL035-060 will tend to dissipate late
this afternoon leaving just cirrus into the night. LIFR
restrictions will be possible at KELM toward morning primarily
from a low ceiling. Boundary layer is looking a bit too breezy
and mixy for fog, but moisture profile leans toward stratus.
Confidence is medium at best.
Gusty SW-SE winds 10-20KTS on average will lose gustiness and a
few knots tonight before becoming primarily SSW 8-12 KTS on
Monday.
Outlook...
Monday and Monday night: Mainly VFR shower chances increase from
northwest to southeast by evening.
Tuesday through Wednesday...Showers with occasional
restrictions possible. Highest chance for restrictions is
Tuesday and Tuesday night.
Thursday...A chance for scattered showers and associated
restrictions.
Friday...Generally VFR. Still a chance for showers.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...None.
NY...None.
&&
$$
SYNOPSIS...MJM
NEAR TERM...MJM
SHORT TERM...MJM
LONG TERM...MJM
AVIATION...JAB

NWS BGM Office Area Forecast Discussion