Chaumont, New York Weather Forecast Discussion

519
FXUS61 KBUF 052330
AFDBUF
Area Forecast Discussion
National Weather Service Buffalo NY
730 PM EDT Fri Sep 5 2025
.SYNOPSIS...
Unsettled weather arrives late tonight, with some rain and then
turning cooler for the weekend. There will be a chance of some lake
effect rain showers east of both lakes on Sunday. High pressure
builds in Monday with dry weather and a day to day warming
trend through midweek.
&&
.NEAR TERM /THROUGH SATURDAY/...
Shortwave energy rounding the base of the trough and the slowly
eastward advancing cold front tonight will bring increasing chances
of rain. The best chance of rain will arrive late tonight and will
then focus from the Southern Tier/Genesee Valley east-northeast into
the Finger Lakes region, and then North Central New York by Saturday
mid-morning. This is where the moisture and frontogenesis
potentially will maximize, depending on how far the front advances
and eventual track of the frontal wave. Ongoing precipitation
Saturday morning across far western New York will ever so slowly
diminish in coverage by mid-afternoon, and then taper off late
across North Central New York. Overall...Saturday is not looking
pleasant but rather damp and definitely on the cool side with Max`Ts
peaking in the 60s.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY NIGHT/...
A long wave trough will be located across the Great Lakes region
late this weekend into next work week, bringing cool and unsettled
weather to the forecast area. Cold air advection will take place,
with 850mb temperatures falling to +3 to +5C through Sunday night.
Initially, drier air will move into the forecast area Saturday
evening and although lake induced instability will be present,
mostly dry weather is expected. Later that night, deeper moisture
will move into the region ahead of an advancing trough, lake effect
rain showers will develop east of Lake Erie and Lake Ontario late
Saturday night and continue into Sunday. Cold air aloft will
generate surface based instability in a well-mixed environment
Sunday and additional showers will develop across the region. A
westerly wind with gusts up to 25 mph and temperatures in the upper
50s to mid 60s will create a fall-like feel to the area.
The trough remains overhead Sunday night through Monday. Much drier
air will filter into the region and any lake effect showers will
dissipate through Monday morning. Surface high pressure will
move across the region Monday to Monday night, which may result
in patchy frost in the western Southern Tier. At this time,
confidence is low due to the fast moving surface high during
this period.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
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 /00Z SATURDAY THROUGH WEDNESDAY/...
A secondary cold front will move east across the eastern Great Lakes
tonight, with a weak wave of low pressure tracking northeast along
this boundary overnight into Saturday. The best chance of rain will
be found from the Southern Tier/Genesee Valley east-northeast into
the Finger Lakes region, and then east of Lake Ontario by mid
Saturday morning.
CIGS will deteriorate to MVFR-IFR within the rain, while mainly VFR
continues at all other terminals.
Outlook...
Saturday...MVFR-IFR within rain, especially over southern and
eastern portions of the area. Elsewhere...mainly VFR.
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...
Winds will diminish somewhat tonight and 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. Given
the much cooler air moving into the eastern Great Lakes, there will
be the chance for lake effect showers, and also waterspouts
beginning late Saturday into Sunday evening. High pressure builds in
on Monday with a period of lighter winds and wave action through
midweek.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...Beach Hazards Statement until 4 AM EDT Saturday for NYZ001-002-
     010-019-085.
     Beach Hazards Statement until 6 AM EDT Saturday for NYZ007.
MARINE...Small Craft Advisory until 10 PM EDT this evening for LEZ020.
         Small Craft Advisory until 4 AM EDT Saturday for LEZ040-
         041.
         Small Craft Advisory until 10 PM EDT this evening for
         LOZ030.
         Small Craft Advisory until 6 AM EDT Saturday for LOZ042.
         Small Craft Advisory from 1 AM to 10 AM EDT Saturday for
         LOZ043-044.
         Small Craft Advisory until 10 AM EDT Saturday for LOZ045.
         Small Craft Advisory until 10 PM EDT this evening for
         SLZ022-024.
&&
$$
SYNOPSIS...AR/TMA
NEAR TERM...AR
SHORT TERM...HSK
LONG TERM...PP
AVIATION...AR
MARINE...AR/Hitchcock/TMA

NWS BUF Office Area Forecast Discussion