173
FXUS61 KBUF 150639
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
139 AM EST Sat Nov 15 2025

.SYNOPSIS...
Low pressure will pass just north of the area this afternoon through
tonight, with rain quickly developing from west to east this
afternoon. The rain will taper off later this evening following the
passage of a cold front. The low will continue to strengthen over
New England tonight through Sunday, producing gusty winds across the
eastern Great Lakes. Colder air behind the system will also bring
lake effect snow showers southeast of the lakes Sunday through
Monday, and some upslope snow for the higher terrain east of Lake
Ontario with light to locally moderate accumulations.

&&

.NEAR TERM /THROUGH TONIGHT/...
Some patchy fog will continue through daybreak, mainly across the
Niagara Frontier. Otherwise, mid/high clouds will thicken and lower
from west to east through the morning hours as warm advection
quickly increases ahead of the next system.

A mid level trough will rapidly sharpen and dig across Ontario and
Quebec this afternoon through tonight, with a deepening surface low
passing just north of the region. DPVA/height falls ahead of the
sharp trough will combine with left exit region upper level jet
support to bring a period of large scale ascent this afternoon and
evening. Increasing moisture transport in the low levels will
accompany a brief period of isentropic upglide ahead of a narrow
thermal ridge, quickly followed by convergence along a strengthening
cold front. Expect rain to rapidly expand in coverage across the
area from midday through mid afternoon. An isolated weak
thunderstorm or two cannot be ruled out given the strong dynamics
and some limited instability, but coverage of thunder will remain
sparse.

The widespread rain will quickly taper off from west to east later
this evening following the passage of the surface cold front. This
will be followed by a brief break of mainly dry weather, with the
possible exception of some lingering upslope showers across higher
terrain. Colder air will pour back into the Great Lakes overnight
behind the departing system, with lake effect showers starting to
increase in coverage southeast of the lakes toward Sunday morning.
Precip type will be all liquid through most of the night, but some
wet snow will start to mix in just before daybreak across higher
terrain.

The rapidly deepening low over New England and the lower Saint
Lawrence Valley overnight will force winds to quickly increase
across the eastern Great Lakes. Expect gusts of 25-35 mph areawide
overnight, and 40-45 mph along the lakeshores.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
The next mid-level low will dive southeast across Manitoba and
Ontario towards northern New York Sunday, before deepening as it
pulls northeast across New England Monday. Meanwhile at the surface,
its attendant low will be in the midst of exiting northeast across
New England Sunday morning. In the wake of the exiting surface low,
cold air will advect into the region under northwest flow,
supporting temperatures at 850mb to drop from -5C to -10C by Sunday
night and Monday morning. With the exiting surface low and the
colder air advecting into the region, widespread precipitation will
become lake enhanced Sunday morning and transition towards pure lake
effect Sunday afternoon and evening. Under the cold air advection
regime, precipitation will gradually shift from rain to snow, from
the higher terrain to the lower elevations throughout the day.

Lake effect bands will become better developed Sunday
afternoon/evening through Sunday night as lake induced equilibrium
levels rise up around 10k feet and the northwest flow will support
lake connections with the Georgian Bay and Lake Huron. Snow
accumulations of a few inches will be possible east and southeast of
Lakes Erie and Ontario, but forecast uncertainty is medium at this
time as guidance continues to depict moving lake effect bands. The
greatest snow amounts can be expected over the higher terrain south
of Buffalo where a better upstream connection is also possible with
Lake Huron and even Lake Superior.

Lake effect will continue Monday and Monday night, as a shortwave
trough passes across the region. Lake snows will linger southeast of
Lake Ontario due to the closer proximity of the exiting trough as
the better fetch off of Lake Ontario. An additional few inches of
snow will be possible Monday, but will be limited due to marginal
daytime temperatures, causing some snow to change over to rain
across the lower elevations.

Otherwise, expect increasing northwest winds on Sunday with gusts up
to 35mph at times. The windiest locations will be better focused
closer to the lakeshores.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
Deep mid-level troughing across the Northeast will pull northeast
into the Canadian Maritimes Tuesday, supporting troughing to pull
away from the region and ridging to build in midweek. Lake effect
showers will continue Tuesday as yet another weak shortwave trough
passes across the region. Lake effect snow showers Tuesday will
gradually diminish, although a few rain/wet snow showers may persist
east/southeast of Lake Ontario Tuesday through early Wednesday.

As ridging builds east mid-week, high pressure will slide across the
Great Lakes supporting a brief period of dry weather. Model guidance
continues to be diverged with the track and timing of the next mid-
level trough and attendant surface low moves out of the Southern
Plains and towards the Ohio Valley. Precipitation chances will
gradually increase from south to north starting Thursday and persist
through Friday. While timing and track of this system continues to
remain diverged between guidance runs and packages, there is
confidence that this system will support mainly rain to start with
the trough advecting warm lower Mississippi Valley air into the
region.

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
Some patchy fog will continue through daybreak across the Niagara
Frontier with local IFR VSBY, including KIAG. Otherwise, mid/high
clouds will thicken and lower from west to east across the region
through the morning hours.

Low pressure will pass by just north of Lake Ontario this afternoon
through tonight. Rain will expand in coverage across the area during
the midday and early afternoon hours, with widespread showers late
afternoon and early evening. There is a low chance of an isolated
weak thunderstorm or two, but coverage would be sparse. The rain
will taper off quickly from west to east later this evening
following the passage of a cold front. Some of the heavier showers
will bring VSBY down to MVFR at times. CIGS will quickly deteriorate
to widespread IFR later today into this evening as the low levels
saturate a few hours after the rain begins.

Overnight, a brief break of mainly dry weather behind the cold front
will give way to increasing lake effect and upslope showers toward
Sunday morning. Precip type will be rain for most of tonight, with
some wet snow mixing in towards daybreak Sunday across higher
terrain with the arrival of colder air. CIGS will improve to
MVFR/lower end VFR by late tonight.

Finally, a strong 50+ knot low level jet will cross the eastern
Great Lakes later this afternoon through tonight. This will result
in a few hours of low level wind shear just ahead of the cold front
while surface winds are still relatively light. Surface gusts will
then ramp up tonight (25-35 knots) with increased boundary layer
mixing behind the cold front.

Outlook...

Sunday...MVFR/local IFR with lake effect rain/snow showers southeast
of the lakes, and upslope snow across higher terrain east of Lake
Ontario.

Sunday night through Monday...MVFR/local IFR with lake effect snow
showers southeast of the lakes and upslope snow showers across
higher terrain east of Lake Ontario.

Tuesday...VFR/MVFR with scattered light lake effect rain/wet snow
showers southeast of the lakes.

Wednesday...VFR.

&&

.MARINE...
Deepening low pressure will pass just north of Lake Ontario this
afternoon through tonight, with this low then deepening further over
New England Sunday before reaching the Canadian Maritimes Monday.
Southerly winds will begin to increase from west to east today, with
winds then veering to the WNW and ramping up significantly tonight
through Sunday. Lower end gales are likely on Lake Ontario late
tonight through Sunday night, with high end Small Craft Advisory
conditions on Lake Erie. Elevated winds and high end Small Craft
Advisory conditions will continue on both lakes Monday before high
pressure begins to build into the Great Lakes Tuesday with
diminishing winds.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...None.
MARINE...Small Craft Advisory from 4 PM this afternoon to 1 PM EST
         Monday for LEZ020.
         Small Craft Advisory from noon today to 1 AM EST Tuesday
         for LEZ040-041.
         Gale Watch from late tonight through late Sunday
         night for LOZ042>045-062>065.

&&

$$

SYNOPSIS...Hitchcock
NEAR TERM...Hitchcock
SHORT TERM...EAJ
LONG TERM...EAJ
AVIATION...Hitchcock
MARINE...Hitchcock