323
FXUS61 KBUF 301823
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
223 PM EDT Thu Jul 30 2026

.WHAT HAS CHANGED...
Only minor changes with this update.

&&

.KEY MESSAGES...
1) Scattered showers and a few storms possible from the Finger
Lakes east through the remainder of the afternoon, otherwise
increasingly drier conditions return through Saturday.

2) Showers and thunderstorms develop for the second half of the
weekend bringing the potential for another round of heavy rainfall.

&&

.DISCUSSION...
Key Message 1...Scattered showers and a few storms possible
from the Finger Lakes east through the remainder of the
afternoon, otherwise increasingly drier conditions return
through Saturday.

The western periphery of persistent stacked low pressure spinning
over southeastern New England will continue to impact portions of
our area through the late afternoon/evening hours while slowly
weakening and ever so slowly starting to exit east off the New
England coast through tonight. Although areas from the Genesee
Valley westward are expected to remain dry, a veil of low cloud
cover will hang in across western NY through the remainder of the
afternoon. Further east, deeper moisture combined with diurnal
heating will keep the threat of widely scattered showers and
possibly an isolated storm two in the forecast for the Finger Lakes
region and points east into the late afternoon/early evening hours.

As deeper moisture associated with this stubborn area of low
pressure finally begins to exit east and drier/air subsidence
attendant to high pressure building in from the west, eastern areas
will finally dry out tonight, with dry and seasonably warm weather
for Friday. Mainly dry and seasonably warm weather is expected to
persist into Saturday, although a modest uptick in humidity levels
in advance of the next system combined with diurnal heating may be
enough to trigger a couple widely scattered showers/storms along any
lake breeze circulation boundaries Saturday afternoon.

Key Message 2...Showers and thunderstorms develop for the second
half of the weekend bringing the potential for another round of
heavy rainfall.

An upper level trough will dig south across the western Great Lakes
Saturday night, while at the same time be in the process of phasing
with a potent mid-level shortwave/attendant surface low diving
southeast into the Ohio Valley. This will result in a
deepening/sharpening mid and upper-level trough that will also slow
its eastward progression. This will allow for a deep southwesterly
flow to develop with warm/humid air being advected in across the
region all the way from the Gulf. This will transport an anomalously
high PWAT airmass northeast into the region late Saturday night and
Sunday with PWAT values possibly approaching 2 inches. In addition,
a 30-40 knot LLJ will move into the region ahead of surface cold
front later Saturday night and Sunday. This will not only give a
boost to the overall forcing, but will result in some breezy to
possibly windy conditions as well. Taking these aforementioned
factors into account, expect a round or rounds of showers and storms
from later Saturday night through at least the day Sunday, and
possibly into Sunday night for which WPC continues with a Slight
Risk (Level 2 of 4) for areas east of the Genesee Valley, with a
Marginal Risk (Level 1 of 4) across the remainder of western NY.

Beyond Sunday, there remains some disagreement amongst medium range
guidance as to the overall pattern evolution going into the first
part of next week. Majority of medium range guidance, including the
NBM have the deeper moisture and more persistent shower activity
pushing east of the area by or during the day Monday with drying
conditions. However, just looking at the overall pattern and some
outliers in the guidance, there is some potential for a cutoff low
to develop somewhere over or near our region first part of next week
as well, which would result in more in the way of at least on and
off showery weather during this timeframe.

&&

.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
Low level moisture pivoting around the backside of a departing low
off the New England coast continues to make its way southward across
our region as of this writing...and is currently resulting in a
swath of mostly MVFR ceilings across much of western New York...with
generally lower-end VFR conditions found elsewhere under developing
diurnal cumulus. As we push through the rest of this afternoon...
north-to-south thinning of the low level moisture and diurnal
influences will help to bring about a return to more widespread VFR
conditions...with any MVFR ceilings likely retreating to the higher
terrain of the Southern Tier and Finger Lakes before dissipating
late in the day. Otherwise conditions will be dry...save for perhaps
an isolated shower/storm or two across the interior of the southern
Tier/Finger Lakes.

Tonight and Friday...dry weather is expected as weak high pressure
settles across the region. Corresponding clearing and light winds
will probably lead to the development of at least some patchy valley
fog across the Southern Tier...and more general patchy fog from the
eastern Finger Lakes northeastward across the North Country where a
little more in the way of residual low level moisture will be in
place. This will result in visibilities falling into the MVFR/IFR
ranges in the above areas. Once we get into the daylight hours of
Friday...renewed diurnal heating should help to mix out any fog by
13z or so...leaving behind widespread VFR conditions for the balance
of the day.

Outlook...

Friday night and Saturday...Mainly VFR.

Saturday night through Sunday night...Periodic showers and
thunderstorms with locally heavy downpours and associated reductions
to MVFR to LIFR, especially from later Saturday night through Sunday
evening.

Monday and Tuesday...Mainly VFR and dry, though a few widely
scattered showers/storms and associated restrictions cannot be ruled
out both days.

&&

.MARINE...
Weak high pressure will settle across the Lower Lakes Region through
Friday...before slowly drifting off the Atlantic coastline on
Saturday. This will provide us with generally light to modest winds
and minimal wave action through Saturday...with the weak pressure
gradient allowing the development of local lake breeze circulations
and onshore flow Friday afternoon.

Between Saturday night and Sunday night an elongating wave of low
pressure and surface cold front will slowly make their way east
across Lakes Erie and Ontario...with a light to modest southerly
flow out ahead of the front giving way to a northerly/northeasterly
flow of similar strength following its passage. Of more concern to
marine interests will be the showers and thunderstorms that are
expected to accompany the frontal passage...some of which could
contain locally heavy downpours/greatly reduced visibility and
locally higher winds and waves.

&&

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

&&

$$

DISCUSSION...JM
AVIATION...JJR
MARINE...JJR