Little Valley, New York Weather Forecast Discussion

187
FXUS61 KBUF 050745
AFDBUF
Area Forecast Discussion
National Weather Service Buffalo NY
345 AM EDT Fri Sep 5 2025
.SYNOPSIS...
Mainly dry weather returns today, although it will become quite
windy, especially northeast of Lake Erie across the Niagara
Frontier. A secondary cold front will cross the region tonight
through Saturday with clouds and some rain, especially from the
Southern Tier through the Finger Lakes to the eastern Lake Ontario
region. This secondary cold front will usher in much cooler air for
the weekend, along with a chance of a few lake effect rain showers
east of Lake Erie and Lake Ontario on Sunday.
&&
.NEAR TERM /THROUGH TONIGHT/...
Dry weather has returned following the passage of the cold front,
with partial clearing across much of the area. The clearing skies,
light winds, wet ground, and saturated low levels have allowed fog
to become widespread across much of the Southern Tier. A Dense Fog
Advisory has been issued for Chautauqua, Cattaraugus and Allegany
counties through mid morning. Some patchy fog will also be found
across Chautauqua County, the western Finger Lakes, and east of Lake
Ontario.
A deep longwave trough will continue to take shape across the
eastern half of Canada today and tonight, with the base of the
trough advancing gradually southeast into the Great Lakes. Another
wave of low pressure will move from near eastern Lake Superior this
morning to James Bay this evening, where it will merge with existing
low pressure over northwest Ontario. A trailing secondary cold front
will approach today, then cross the eastern Great Lakes tonight.
Mainly dry weather will continue today. The main story will be wind,
as a 50 knot low level jet ahead of the trough axis propagates into
the area. The strongest low level jet segment will move up Lake Erie
and cross the Niagara Frontier later today. Forecast BUFKIT
soundings show steep low level lapse rates and a deeply mixed
boundary layer this afternoon, that will allow for efficient
downward transfer of stronger momentum from aloft. This should
support several hours of 45-50 mph wind gusts across Niagara and
northern Erie counties this afternoon. A Wind Advisory has been
issued for these areas. Elsewhere, expect wind gusts in the 25-35
mph range later today. Winds will quickly diminish after sunset as
the low level jet diminishes, and the boundary layer stabilizes with
the onset of nocturnal cooling.
Tonight, the secondary cold front will move east across the area.
Another shortwave and upper level jet streak will round the base of
the trough and strengthen over the northeast US and southeast Canada
late tonight. Forcing atop the advancing cold front will allow a
baroclinic wave to develop and ripple northeast along the boundary,
with associated differential temperature advection supporting
thickening clouds and showers. The best chance of rain late tonight
will be from the Southern Tier into the Finger Lakes and Central NY
where moisture and frontogenesis maximize, with the lowest chances
close to the Canadian border.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY NIGHT/...
A deep and dynamic upper level troughing pattern will continue to
dominate the Northeast Saturday through Monday. The period will open
Saturday with ongoing widespread showers across the interior as a
wavy cold frontal boundary pushes east of the forecast area. Behind
this FROPA, a cool Canadian airmass will continuously spill into the
region with 850mb temps dipping as low as +1 to +3C by Monday
morning. This will lead to a stretch of sfc temps more akin to early
October rather than early September. Once reinforcing synoptic
moisture arrives, areas east and northeast of the lakes will also
contend with periodic lake effect rain showers. These will likely
begin to develop Saturday night once the dry slot behind the front
moves east of the lakes, and may continue well into Monday. With
diurnal instability and relatively steep lapse rates, showers on
Sunday may develop outside the main lake effect areas.
A progressive sfc-850mb ridge will move squarely over the eastern
Great Lakes later Monday into Monday evening, then shift off to New
England by early Tuesday morning. This should effectively taper off
the last of the lake response while also potentially setting the
stage for some frost across the interior Monday night. Still some
question with how quickly the high moves east, which could moderate
the airmass and lead to enough southerly flow to preclude frost
though will need to continue monitoring.
&&
.LONG TERM /TUESDAY THROUGH THURSDAY/...
A wedge of sfc high pressure and associated dry air will extend back
down the spine of the Appalachians and Ohio Valley from the Canadian
Maritimes through midweek. This will maintain quieter weather across
the eastern Great Lakes through at least Wednesday and allow for a
gentle warming trend, with temps briefly recovering back to near
normal. Aloft, an initial period of quasi-zonal flow across the
Northeast will give way to broad scale troughing pivoting south from
Canada sometime later Wednesday into Thursday. An associated sfc low
far to the north will push another cold front south into the region
with temps falling back below normal. There could be some shower
activity with this feature especially across the North Country
though given typical long range uncertainties in track, strength and
timing will stick with NBM`s mainly dry forecast.
&&
.AVIATION /08Z FRIDAY THROUGH TUESDAY/...
Areas of fog will continue through early to mid morning, especially
across the Southern Tier where fog will be dense with LIFR
conditions. Farther northeast, expect some patchy fog and local IFR
from the western Finger Lakes to areas southeast and east of Lake
Ontario. The fog and low stratus will burn off around mid morning.
Dry weather has returned today behind the first of two cold fronts,
with VFR prevailing once the fog and low stratus dissipates. It will
become quite windy today as a 50 knot low level jet propagates
across the eastern Great Lakes. A deeply mixed boundary layer and
steep low level lapse rates will allow for efficient transfer of
stronger momentum aloft down to the surface, translating to wind
gusts of 35-40+ knots northeast of Lake Erie near KIAG and KBUF.
Wind gusts of 20-30 knots will be common elsewhere.
Tonight, the second cold front will move east across the eastern
Great Lakes. A weak wave of low pressure will ripple northeast along
the frontal boundary overnight, supporting thickening clouds and
rain showers expanding in coverage. The best chance of rain will be
found from the Southern Tier into the Finger Lakes to points south
and east of Lake Ontario late tonight, with the lowest chance near
the Canadian border. CIGS will deteriorate to MVFR within the rain,
while VFR continues elsewhere.
Outlook...
Saturday...VFR/MVFR with showers likely, especially over southern
and eastern portions of the area.
Sunday...VFR/MVFR with a chance of showers, especially east of Lake
Erie and Lake Ontario.
Monday...Mainly VFR. Slight chance of showers and MVFR east of Lake
Erie and Lake Ontario.
Tuesday...Mainly VFR.
&&
.MARINE...
A period of strong southwest winds will develop today ahead of a
secondary cold front on Lake Erie and the west end of Lake Ontario,
bringing another round of solid Small Craft Advisory conditions.
Winds will also become quite gusty along the Saint Lawrence River
for a few hours this afternoon. The stronger winds will spread to
the east end of Lake Ontario tonight.
Winds will diminish somewhat Saturday, but will still produce very
choppy conditions on both Lake Erie and Lake Ontario. The very
choppy conditions will continue Sunday, and winds may increase
further to support Small Craft Advisory conditions.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...Wind Advisory from noon today to 8 PM EDT this evening for
     NYZ001-010.
     Beach Hazards Statement from 1 PM EDT this afternoon through
     late tonight for NYZ010-019-085.
     Dense Fog Advisory until 9 AM EDT this morning for NYZ019.
     Dense Fog Advisory until 9 AM EDT this morning for NYZ020-021.
MARINE...Small Craft Advisory from 11 AM this morning to 10 PM EDT this
         evening for LEZ020.
         Small Craft Advisory from 8 AM this morning to 4 AM EDT
         Saturday for LEZ040-041.
         Small Craft Advisory from 11 AM this morning to 10 PM
         EDT this evening for LOZ030.
         Small Craft Advisory from 11 AM this morning to 6 AM EDT
         Saturday for LOZ042.
         Small Craft Advisory from 1 AM to 10 AM EDT Saturday for
         LOZ043-044.
         Small Craft Advisory from 7 PM this evening to 10 AM EDT
         Saturday for LOZ045.
         Small Craft Advisory from 1 PM this afternoon to 10
        PM EDT this evening for SLZ022-024.
&&
$$
SYNOPSIS...Hitchcock
NEAR TERM...Hitchcock
SHORT TERM...PP
LONG TERM...PP
AVIATION...Hitchcock
MARINE...Hitchcock

NWS BUF Office Area Forecast Discussion