117
FXUS61 KBUF 302354
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
754 PM EDT Mon Jun 30 2025

.SYNOPSIS...
A warm and humid day today ahead of the next approaching cold front.
Showers and thunderstorms are expected during the afternoon and into
the overnight, with some of the showers and storms capable of
producing heavy rainfall at times. Showers and thunderstorms will
linger through the day Tuesday, especially for the eastern half of
the area.

&&

.NEAR TERM /THROUGH TUESDAY/...
A warm front is across western NY this afternoon, and will continue
to move northward through this evening. The combination of
temperatures in the 80s and dewpoints in the upper 60s to low 70s
has led to heat index values in the upper 80s to low 90s across
western NY/south of the warm front this afternoon. The greatest heat
indices will be confined to the lake plains south of Lake Ontario
and into the Genesee Valley. This moist airmass is associated with
anomalously high PWAT air. An axis of 2"+ remains south of the
forecast area but will advect northward through tonight. Scattered
showers and a few rumbles of thunder have been ongoing south of the
warm front, across southwest NY. This activity will expand northward
in coverage with additional heavy showers and thunderstorms moving
into the region from the southwest. Heavy rain is the main risk with
thunderstorms across western NY into this evening, however modest
shear may be enough to produce a few strong to severe thunderstorms.
Repeated rounds of showers and thunderstorms may result in localized
flash flooding, especially across the Chautauqua and Cattaraugus
counties with 1-HR FFG around 1.5". Shear and the loss of surface
based instability into the evening hours should help keep things
moving however, localized flash flooding is possible across the
Niagara Frontier into the Finger Lakes region into this evening. A
Flood Watch for Chautauqua and Cattaraugus counties is in effect
until 10PM.

Drier and less humid weather conditions will persist east of Lake
Ontario. Showers and a few storms are possible as the warm front
lifts through tonight. Heavy rain is possible with any
thunderstorms. There remains a low to medium chance for showers and
a few thunderstorms across western NY tonight with no obvious
forcing mechanism overnight.

A cold front/surface boundary will move through the forecast area
Tuesday. There is minimal cold air advection behind the boundary,
however deeper moisture will diminish in it`s wake. Modest surface
based instability will support a few showers and thunderstorms,
mainly across the Finger Lakes where moisture lingers longest. A
southwest wind will stabilize areas east of the Lakes. A convergence
zone may develop across the Niagara Frontier Tuesday afternoon with
showers and a few rumbles of thunder possible.

&&

.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/...
Fair weather through much of this period, with a shortwave trough
passing Wednesday night and Thursday creating scattered showers and
thunderstorms upon it.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
This period starts with fair weather as a ridge of high pressure
pushes towards our region and trough over eastern Canada departs.
Quiet weather for the Fourth of July with temperatures near seasonal
normals and winds light.

We`ll tack on 5-10 degrees to the temperatures for Saturday and
Sunday ahead of a weak cold front that will settle across our region
to close out the holiday weekend with chances for showers and
thunderstorms on Sunday.

&&

.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
Organized showers and thunderstorms have become very common
across the area this evening as a warm front has passed north.
This has left a sultry air mass in its wake with heavy rainfall
resulting from thunderstorms as a result. This is leading to low
visibility and low cigs with these thunderstorms. This is likely
to continue for a few more hours at most terminals. Overnight,
as the thunderstorm activity wanes, residual low level moisture
seems likely to result in stratus and fog at most sites around
or shortly after 06z. This is likely to linger at all sites
until Tuesday early afternoon.

Outlook...

Tuesday...Early day IFR with low clouds and/or fog then
MVFR/VFR with a few showers and thunderstorms.

Wednesday...VFR.

Thursday...Mainly VFR. Showers and thunderstorms possible.

Friday and Saturday...VFR.

&&

.MARINE...
A departing area of high pressure will maintain light winds today.
Waves are expected to remain below a foot.

A warm front will lift across the Lower Great Lakes today, with
light winds on Lake Ontario backing to easterly through the day and
before the warm front passes through. Behind the warm front a 10 to
15 knot south-southwesterly flow will be found tonight creating a
chop on the waters.

The winds and waves are expected to remain below small craft
criteria through mid week though some choppy conditions will be
possible at times.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...Flood Watch until 10 PM EDT this evening for NYZ019-020.
MARINE...None.

&&

$$

SYNOPSIS...SW
NEAR TERM...HSK
SHORT TERM...Thomas
LONG TERM...Thomas
AVIATION...Fries
MARINE...Thomas