Java Lake, New York Weather Forecast Discussion

364
FXUS61 KBUF 061037
AFDBUF
Area Forecast Discussion
National Weather Service Buffalo NY
637 AM EDT Sat Sep 6 2025
.SYNOPSIS...
Rain showers will spread northeast into the region this morning,
particularly across eastern portions of the area as a weak wave of
low pressure moves along a cold front. Cool temperatures with
periodic lake effect rain showers will persist tonight through
Sunday in the wake of this front. Drier weather arrives Monday as
high pressure builds over the region, with a warming trend then
emerging through midweek.
&&
.NEAR TERM /THROUGH TONIGHT/...
Deep longwave troughing will slowly advance across the eastern CONUS
and Canada through tonight. Several shortwaves will concurrently
round the base of this trough and move across the Great Lakes,
leading to increased chances for rain. The first of these waves will
track northeast behind a cold front across central NY this morning,
with resultant showers moving across the interior Southern Tier
and Finger Lakes to the Tug Hill region through the early
afternoon. Lake enhanced/upslope rain showers are also possible
east of Lake Erie through the day, though with the system`s mid-
level dry slot overhead would expect these to be spotty.
Otherwise, with 850mb temps only around +7C afternoon highs will
feel more akin to early October as opposed to early September.
Additional synoptic moisture will move back into the eastern Great
Lakes region behind the dry slot tonight, causing steadier lake
effect rain showers and perhaps a few thunderstorms to develop. The
main bands should initially setup east-northeast of both lakes,
though the general steering flow becoming more westerly behind a
passing weak shortwave should direct the showers more east of Lake
Erie later in the night. Otherwise, the cool temperatures will
continue with many areas ranging in the 40s to near 50 for overnight
lows.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
A strong mid level shortwave will move east across the eastern Great
Lakes Sunday. Deeper moisture and the strongest forcing will remain
well north of the US/Canadian border, but the passage of the trough
and associated cold air aloft will continue to support lake effect
rain showers.
Off Lake Erie, expect lake effect rain showers Sunday morning east
of the lake from southern Erie/Wyoming counties into the western
Southern Tier. These will diminish in coverage through the day, and
end by late afternoon. Off Lake Ontario, expect a more organized
band of lake effect rain over Jefferson County in the morning,
drifting south to the Tug Hill region by late morning and then
breaking up into scattered showers in the afternoon. A few more lake
effect rain showers may develop Sunday night across Oswego County
and the southern Tug Hill, but these too will end by Monday morning
as dry air and subsidence build into the eastern Great Lakes.
A deep longwave trough over central and eastern Canada and adjacent
lower 48 states will lose amplitude and retreat back northward early
next week, with its influence diminishing across the Great Lakes by
Monday. Surface high pressure will drift east across the Ohio Valley
and Great Lakes Monday through Monday night, with dry weather and
mainly clear to partly cloudy skies. The airmass will remain cool,
and strong radiational cooling may bring a risk of patchy frost to
the coldest southern Tier Valleys Sunday night and Monday night.
Some patchy frost may also develop across the colder North Country
locations Monday night.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
An extended period of mainly dry weather will continue Tuesday
through the end of next week. Surface high pressure and a wedge of
dry air will remain in place from the eastern Great Lakes to New
England Tuesday through Wednesday. Temperatures will warm back to
near or slightly above average after the cool weekend.
A cold front will then move south across the area Thursday as a
shortwave amplifies the trough over eastern Canada. This cold front
will be moisture starved, with little more than an increase in cloud
cover and slight chance of a light shower or two. High pressure will
build back into southeast Canada and the Northeast US by Friday,
with dry and somewhat cooler weather.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
A wave of low pressure will track northeast across a slowly
advancing cold front across eastern portions of the region. This
will cause numerous rain showers to spread across the Southern
Tier and northeastward up through the Finger Lakes and North
Country. This main area of precip will then slowly drift
eastward and out of the forecast area through about 18z. Lighter
shower activity can`t be ruled out further west through the
morning hours.
Cigs/vsbys are expected to deteriorate to mainly MVFR within the
steadier rains while remaining VFR elsewhere.
A few spotty lake enhanced/upslope showers may develop east of Lake
Erie this afternoon, though steadier bands of lake effect rain and
possibly a few thunderstorms are expected tonight mainly after 06z.
These may initially set up near KART and near or just south of KBUF
with localized MVFR conditions. The activity off Lake Erie will
likely shift southward into the Southern Tier thereafter.
Outlook...
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 and Wednesday...VFR.
&&
.MARINE...
Wave action on both lakes will remain quite choppy especially across
the eastern end of Lake Ontario as the region sits behind a slow
moving cold front, though winds/wave heights should remain below SCA
criteria. Winds are expected to pick back up for a brief period on
Lake Erie later this afternoon into this evening with a window
of marginal SCA conditions.
After winds on Lake Erie relax late this evening, winds on both
lakes will strengthen again early Sunday with another round of
Small Craft conditions likely into Sunday night. With the cool
airmass overhead, lake effect rain showers, thunderstorms, and
waterspouts will also be possible at times. The primary
timeframe of concern for these will be tonight through Sunday
morning.
High pressure building over the lakes will cause winds to subside
Sunday night into Monday, becoming light by Monday evening.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...None.
MARINE...Small Craft Advisory from 1 PM this afternoon to 2 AM EDT
         Sunday for LEZ040-041.
&&
$$
SYNOPSIS...PP
NEAR TERM...PP
SHORT TERM...Hitchcock
LONG TERM...Hitchcock
AVIATION...PP
MARINE...PP

NWS BUF Office Area Forecast Discussion