240
FXUS61 KBUF 011438
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
1038 AM EDT Sat Nov 1 2025

.SYNOPSIS...
A cooler airmass will flow over the Lower Great Lakes this weekend
with localized bands of lake effect rain southeast of the Lakes
through Sunday morning. Surface high pressure will build towards our
region Sunday, ending the lake response while also allowing for a
bit more sunshine, though temperatures will remain near normal. The
next storm system will arrive to our region Monday, with a gusty
southwest wind ahead of a cold front that will bring another round
of showers.

&&

.NEAR TERM /THROUGH SUNDAY/...
A cool day today with a limited lake effect response southeast of
the Lakes. While temperatures at 850 hPa of -3 to -5C will be cool
enough to generate lake instability, deeper ambient moisture will
exit with the departing storm system, leaving less favorable
moisture profiles over the Lower Great Lakes for bands of lake
effect rain to form. Overall bands of lake effect rain will generate
rainfall on the order of a tenth or two. These bands of rain will
likely weaken and become more cellular through the afternoon hours
with diurnal effect disrupting the bands.

High pressure at the surface will begin to build towards our region
later tonight and into Sunday, which will back the wind flow. While
a shortwave trough diving towards the Ohio Valley late tonight will
bring back favorable moisture over Lake Erie, the increase in
directional wind shear and slight warming of the airmass will likely
result in no uptick in band strength over Lake Erie.

Any lake effect rain southeast of Lake Ontario will end early Sunday
morning with the increased wind shear and now drier airmass. We
should see a return to a fair amount of sunshine over the northern
two thirds of our CWA Sunday, but the shortwave trough over the Ohio
Valley will likely leave a deck of mid level clouds over the
Southern Tier and the hills south and east of Buffalo.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
Weak area of high pressure will depart from our region to the east
Sunday Night, ahead of the next shortwave trough. Vigorous PV
anomaly down to around 500 hPa will deepen this shortwave
trough...with the PV anomaly tracking along Lake Ontario and to
points eastward. An increase in the surface pressure gradient within
this trough will bring gusty southwest winds to our region Monday,
with the strongest gusts found downwind of the Lower Great Lakes.
Ahead of a cold front rain showers will develop and pass through our
region Monday afternoon and evening. Highest chances will be towards
the north, closer to the base of the mid level trough and deeper
moisture. Another area of high pressure behind the front will bring
back fair weather for Tuesday and Tuesday night to our region.

&&

.LONG TERM /WEDNESDAY THROUGH FRIDAY/...
Another Pacific shortwave trough will reach our region Wednesday and
Wednesday night with a period of rain showers ahead of a cold front
passage. The progressive nature of this trough will allow for the
rain showers to end by early Thursday as another area of high
pressure brings back fair weather to close out this forecast period.

&&

.AVIATION /14Z SATURDAY THROUGH WEDNESDAY/...
Moist, cyclonic flow will continue across the eastern Great Lakes
today. Isolated to scattered lake effect clouds and showers will
persist across the western Southern Tier and southeast of Lake
Ontario, mainly from KROC to KFZY. Mainly VFR conditions across
the region. Wouldn`t rule out ceilings dropping to 2-3k feet
at KJHW, KROC, and KART this morning.

VFR conditions are expected across the region later today
through tonight. Lake effect showers will diminish today. There
is high confidence that VFR will persist across the Niagara
Falls/Buffalo region. Lighter winds (8-12kts) are expected
today, becoming variable or calm overnight.


Outlook...

Sunday...Mainly VFR. A slight chance of a shower ESE of Lake
Ontario with MVFR ceiling heights early.

Monday...VFR becoming MVFR/IFR. Breezy southwest gusts downwind of
the Lakes. Rain showers likely. Lowering ceiling heights across
higher terrain and east of Lake Ontario. Rain showers taper off
Monday night.

Tuesday...Becoming mainly VFR. A chance of a shower east of Lake
Ontario.

Wednesday...MVFR/VFR. Rain showers late.

&&

.MARINE...
Behind a departing deep storm system west to northwest winds today
will begin to slowly relax, with waves diminishing below four feet
through the day on Lake Erie, and then by evening along the southern
lake Ontario shoreline. Associated small craft advisories will end
with the diminishing wave heights. Along a convergent lake effect
boundary there will be a small chance for waterspout formation on
Lake Erie tonight.

Winds will weaken further on Sunday, and back to a southwest wind
direction early in the day. This will maintain low wave heights on
the eastern Great Lakes.

Ahead of a well defined shortwave trough these southwest winds will
increase through the day Monday. Southwest winds to 30 knots are
expected on both Great Lakes...with a decent flow continuing down
the Saint Lawrence river. Additional small craft advisories are
likely starting Monday morning, with poor boating conditions likely
to continue through much of the work week on the Great Lakes.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...None.
MARINE...Small Craft Advisory until 4 PM EDT this afternoon for LEZ040-
         041.
         Small Craft Advisory until 5 PM EDT this afternoon
         for LOZ042.
         Small Craft Advisory until 10 PM EDT this evening for
         LOZ043>045.

&&

$$

SYNOPSIS...Thomas
NEAR TERM...Thomas/TMA
SHORT TERM...Thomas
LONG TERM...Thomas
AVIATION...HSK/TMA
MARINE...Thomas