000
FXUS61 KBUF 011014
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
614 AM EDT Tue Sep 1 2026

.WHAT HAS CHANGED...
Minor changes to the forecast with this update.

&&

.KEY MESSAGES...
1) Active weather pattern through midweek with multiple rounds of
showers and thunderstorms, including severe thunderstorm potential
mainly late Wednesday through Wednesday night.

2) Warm and very humid today through Wednesday with a heat index in
the lower 90s Wednesday across portions of Western and Central NY.

&&

.DISCUSSION...
KEY MESSAGE 1...Active weather pattern through midweek with multiple
rounds of showers and thunderstorms, including severe thunderstorm
potential mainly late Wednesday through Wednesday night.

A northwest to southeast oriented complex frontal zone will remain
in place across the Great Lakes through midweek, with an active
pattern continuing. The greatest timeframe of concern will be late
Wednesday afternoon through the first half of Wednesday night, when
the severe weather and flash flooding potential peak.

Today, a mid level shortwave will continue to move southeast across
northern and eastern NY through early to mid morning. Large scale
ascent from the shortwave will combine with frontogenesis and
moisture convergence along the frontal zone to support periods of
rain across Central NY and the North Country, but this will taper
off later this morning. Farther west, weaker forcing will only
support a few scattered showers across Western NY and the Genesee
Valley through early to mid morning. There may be a few embedded
rumbles of thunder, but coverage of any thunderstorms will remain
sparse through this morning.

This afternoon, subsidence and a bubble of drier mid level air
behind the departing shortwave will keep much of the area dry. The
combination of diurnal heating, warm advection, and the arrival of
another shortwave late in the day may support a few more scattered
showers and thunderstorms across Central NY and the North Country,
especially across higher terrain. Farther west, a few isolated
showers and thunderstorms may develop along the lake breeze
convergence zone from the Niagara Frontier east across the Genesee
Valley and western Finger Lakes, but otherwise expect dry weather to
prevail in most areas.

Tonight, any spotty showers and thunderstorms will end in the
evening with the loss of daytime heating. Dry weather will then
prevail most of the night. A few showers and isolated thunderstorms
may move into Western NY very late tonight or early Wednesday
morning as the weakening remnants of upstream convection move into
the area.

Wednesday through Wednesday night, a strong mid level trough will
advance east across Ontario and Quebec, with height falls and DPVA
spreading into the Great Lakes in the afternoon and evening. An EML
will be captured and advected to near Lake Erie, with EML induced
capping allowing a reservoir of strong instability to develop across
the southern Great Lakes. Convective initiation will focus along the
northern edge of the EML where rising parcels can more easily breach
the EML induced cap, with this occuring upstream during the
afternoon with the arrival of large scale ascent. Clusters of
convection will move ESE across the eastern Great Lakes from late
afternoon through the first half of Wednesday night.

Severe Weather Potential:

Today through tonight, the severe weather potential will remain low
but non-zero across the area. A notable lack of forcing for ascent
from synoptic scale or meso-alpha scale features combined with
warm/dry mid levels will likely keep any coverage of deep moist
convection sparse this afternoon and evening. Effective shear is
also quite modest today, with 20-30 knots of flow through the mid
levels. Strong surface based instability will develop this
afternoon, so if any isolated convection does form there will be a
risk of isolated strong wind gusts and hail, but this will be the
exception rather than the rule.

Late Wednesday through Wednesday night continues to look much more
interesting, with strong instability, strong shear, and sufficient
forcing all potentially aligning in time and space. Strong
instability and strong effective shear will potentially support all
convective modes, including bowing segments and supercell
structures. The strong shear is producing elongated hodographs in
forecast soundings, although low level hodograph curvature is
relatively modest in largely unidirectional flow. The primary hazard
will be damaging wind gusts, with a lower secondary risk of isolated
large hail. PWAT values approaching 2 inches will also support some
flash flood potential if training occurs. An isolated tornado cannot
be ruled out given the forecast shear profiles. Ultimately, the
degree of severe potential will hinge in timing and placement of
mesoscale features which cannot be reliably resolved in model
guidance at this time range. Stay tuned.

KEY MESSAGE 2...Warm and very humid today through Wednesday with a
heat index in the lower 90s Wednesday across portions of Western and
Central NY.

Humidity will build today and continue through Wednesday, with
surface dewpoints rising into the upper 60s to lower 70s areawide.
Dewpoints may approach the mid 70s at times along lake breeze
boundaries where low level moisture convergence maximizes. Clouds
will help to hold temperatures down somewhat today, with highs in
the lower 80s across Western and Central NY with a peak heat index
in the upper 80s this afternoon.

Temperatures will likely be warmer Wednesday with less cloud cover
through the heat of the day. Expect highs in the mid 80s across
Western and Central NY, with some of the warmer inland valleys in
the upper 80s. Peak heat index values will reach the lower 90s.

The frontal zone will gradually drift south Thursday, then move well
south and west of the area by Friday. A cooler and much less humid
airmass will arrive by Friday, and remain in place through the
upcoming holiday weekend.

&&

.AVIATION /10Z TUESDAY THROUGH SATURDAY/...
A mid level shortwave crossing northern NY will combine with a
stalled frontal zone over the eastern Great Lakes to support areas
of rain this morning across Central NY and the North Country.
Farther west, any showers will be more scattered in nature across
Western NY. Some limited elevated instability may support isolated
embedded thunder, but coverage of any thunderstorms will remain
sparse through this morning. CIGS/VSBY will be mainly VFR, with some
MVFR and local IFR in the steadier rain across the North Country.

This afternoon, areas of MVFR CIGS will continue across portions of
Central NY and the North Country, with mainly VFR across Western NY,
the Genesee Valley, and western Finger Lakes. A few isolated to
widely scattered showers and thunderstorms may develop this
afternoon and evening, but most of the time will be rain free. The
best chance of a few spotty showers and storms will be across the
higher terrain of Central NY and the North Country. A lake breeze
driven convergence zone may also support a few isolated
thunderstorms from the Niagara Frontier east across the Genesee
Valley and western Finger Lakes from mid afternoon through early
evening.

Tonight, any isolated showers and storms will dissipate this evening
with the loss of daytime heating. Mainly dry weather will then
prevail most of the night. A few showers and scattered thunderstorms
may arrive very late tonight or early Wednesday morning across
Western NY from the weakening leftovers of upstream convection. Low
level moisture will likely support the development of fog/BR and
some low stratus overnight, with areas of MVFR/IFR CIGS/VSBY
developing.

Outlook...

Wednesday through Wednesday night...Occasional showers and
thunderstorms, especially late Wednesday through Wednesday night.
Some storms may be strong with locally gusty winds, hail, and
torrential downpours. VFR/MVFR, with local IFR in storms.

Thursday...VFR/MVFR with a chance of showers and thunderstorms,
mainly across the Southern Tier and Finger Lakes.

Friday and Saturday...Mainly VFR. River valley fog with local IFR
each late night and early morning across the Southern Tier.

&&

.MARINE...
A frontal zone will remain draped across the Great Lakes through
Thursday. Southwest winds will increase into the 10-15 knot range on
Lake Erie today and again Wednesday, producing a light to moderate
chop. Winds will be lighter and more variable on our other Great
Lake. The front will move south of the region by late Thursday
through Friday, with west to northwest winds and a light chop in its
wake. Winds and waves will remain below Small Craft Advisory
criteria through the upcoming holiday weekend.

There will be a chance of thunderstorms at times through midweek.
Thunderstorm chances will peak late Wednesday afternoon through the
first half of Wednesday night. Some of these storms may contain
strong winds, hail, and locally higher waves.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...None.
MARINE...None.

&&

$$

DISCUSSION...Hitchcock
AVIATION...Hitchcock
MARINE...Hitchcock