760
FXUS61 KBUF 251754
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
154 PM EDT Wed Jun 25 2025

.SYNOPSIS...
A wavy stationary front will linger across western NY today. Some
showers and thunderstorms are expected along the front, especially
for this afternoon as the front stalls near and just south of the
NY/PA border. Showers and thunderstorms are capable of heavy
downpours and gusty winds. The end of the week into the first half
of the weekend will become more active as a disturbance tracks near
the region.

&&

.NEAR TERM /THROUGH THURSDAY/...
A wavy stationary front stretches from Lower Michigan to western
NY, with another segment of a front across the northern shore
of Lake Ontario into the Saint Lawrence Valley this afternoon.
A humid airmass is in place across the region with a PWAT from
the 12z kbuf raob of 1.92 inches (1.98" is the daily max.)
Heavy showers will sag south across the southern portion of the
Niagara Frontier and Genesee Valley this afternoon. Mesoanalysis
shows instability of 1-2k J/Kg just south of these showers. As
the front sags southward today, additional showers and
thunderstorms will develop across the western Southern Tier. A
west- northwest to east-southeast storm motion may result in
training thunderstorms into this evening. Heavy downpours and
localized flash flooding are possible, with 30-50% HREF
probability of greater than an inch in three hours in localized
areas in Cattaraugus and Allegany counties.

A ridge will remain across the southeast U.S. through Thursday. A
corridor of deep moisture will persist across the forecast area. The
weak front will move south of the forecast area through the first
half of tonight. This will keep the better forcing for showers and
thunderstorms south of the forecast area. The front will lift into
western NY late tonight through Thursday morning before moving back
south-southeast Thursday afternoon. An area of showers and a few
thunderstorms is becoming increasingly likely across western NY late
tonight into Thursday morning. While the thunder risk is low, skinny
CAPE, short MBE vectors, and high 1000-500mb RH% will result in
heavy downpours in showers. There remains some uncertainty with the
northward extend of the front Thursday, but consensus has it up to
the southern shore of Lake Ontario. The front will move back south
Thursday afternoon and should dry out areas across western NY, with
lingering showers across interior locations. A weak disturbance may
produce some showers across the Saint Lawrence Valley Thursday
afternoon.

There is a Marginal Risk of Excessive Rainfall for western NY
through Thursday night. Training storms and heavy rain are possible
in the outlook areas, however the threat seems isolated.

&&

.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY NIGHT/...
The eastern Great Lakes will remain situated on the northern
periphery of a weak ridge of high pressure across the southeastern
CONUS through the end of the week. Concurrently, a diffuse
negatively tilted mid-level shortwave and associated sfc low
pressure will gradually slide northeast from the Upper Midwest
across Ontario and Quebec. As this feature impinges on the region,
it will drag a stalled frontal boundary across the Ohio Valley and
SW Pennsylvania back northward as a warm front. The increased
forcing overlaid with the already humid (though not overly hot)
airmass in place will lead to more widespread unsettled weather with
opportunities for showers and thunderstorms. While the severe risk
may be nonzero, much of the focus for this period will be on the
potential for locally heavy rainfall, particularly Friday afternoon
through early Saturday. Sounding climatology/analysis show PWATs are
expected to top out near 2", likely exceeding the daily max which
combined with tall skinny CAPE profiles and short MBE vectors,
should lead to efficient warm cloud rain processes and some
potential for training storms. Uncertainty remains high in QPF
placement and magnitude; NBM probabilities indicate that the Tug
Hill region may have the greatest chance of seeing locally
heavy rainfall, though percentile spread is notably high in this
area. Chances for showers and thunderstorms will taper off
Saturday and Saturday evening behind the sfc low`s weak cold
front, with mainly dry weather prevailing by Saturday night.

&&

.LONG TERM /SUNDAY THROUGH TUESDAY/...
Zonal flow over weekend will give way to a deepening trough carving
out across the Great Lakes early next week. Expect a brief period of
dry weather Sunday as a progressive area of sfc high pressure over
the Ohio Valley crests over the region. With trough then gradually
encroaching on the region, chances for showers and thunderstorms
will increase across the area into the start of the new work week as
a cold front approaches and crosses the area. Lower-end chances for
showers behind this front on Wednesday as longwave troughing may
linger across Quebec.

Otherwise, the seasonable but above normal temperatures for late
June will peak on Monday. Then in the wake of a cold frontal
passage, temperatures will fall back to near normal for the start of
July.

&&

.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
A wavy front will move across western NY through tonight with
showers and thunderstorms possible across interior portions of
western NY, mainly the Southern Tier through this evening. The front
will return late tonight into Thursday with showers developing
across western NY. A humid airmass will result in heavy downpours
even outside of thunderstorms. Sudden reductions in visibility are
possible in heavy showers. The threat for thunder remains low
tonight through Thursday morning.

Prevailing VFR conditions are expected in through Thursday morning.
As mentioned above, brief and sudden flight restrictions are
possible in any showers and thunderstorms.

Outlook...

Thursday...A few showers and thunderstorms at times. Mainly VFR,
with local/brief restrictions in thunderstorms.

Friday...Restrictions likely with more widespread shower and
thunderstorm development expected.

Saturday...Improvement to mainly VFR with chances for showers and
thunderstorms diminishing from northwest to southeast.

Sunday...Mainly VFR. A low chance of showers and thunderstorms.

Monday...A few showers and thunderstorms at times. Mainly VFR, with
local/brief restrictions in thunderstorms.

&&

.MARINE...
A weak cold front will sag south across the area this morning,
shifting winds to the northeast today and lasting into the end of
the week and supporting at times a light to moderate chop. A few
rounds of afternoon/evening showers and thunderstorms (and locally
higher gusts associated with the stronger storms) will be possible
each day through the end of the week.

&&

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

&&

$$

SYNOPSIS...HSK/SW
NEAR TERM...HSK
SHORT TERM...PP
LONG TERM...EAJ/PP
AVIATION...HSK
MARINE...EAJ/PP