910
FXUS61 KBUF 190705
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
305 AM EDT Tue Aug 19 2025

.SYNOPSIS...
High pressure will remain across the Northeast today, providing
mostly dry weather. An area of low pressure will approach the region
tonight and showers and a few thunderstorms will be possible through
Wednesday. Dry weather will return late in the week as high pressure
builds into the region.

&&

.NEAR TERM /THROUGH TONIGHT/...
High pressure is centered across northern Quebec and dry weather and
light southerly winds will continue through the morning hours.

A shortwave trough will approach the forecast area today. Surface
low pressure and a plume of moisture across the central Great Lakes
will move eastward, while a warm front moves into western NY by
this evening. As high pressure moves east, a surface trough
will set-up across the forecast area. Widely scattered showers
are possible as low-level convergence increases, however the
greater ascent will reach the area tonight.

Increasing forcing and theta-e advection ahead of the surface low
will result in showers and thunderstorms across the forecast area
tonight. High moisture content with warm cloud depths over 12k feet
should result in moderate to heavy rain at times. Rainfall amounts
will likely be highest just south of Lake Ontario, at the
intersection of the nose of a 30kt low level jet and surface trough.
Average basin amounts in this location will likely exceed 0.75".
Lesser amounts expected across the western Southern Tier and
North Country. Due to the dry antecedent conditions, there is a
low risk for flooding, however due to the moist environment
can`t rule out isolated flash flooding in areas of poor
drainage. CAMS show weak elevated instability with 25kts of
0-6km shear overnight across western NY. While the region is
in a general thunderstorm risk, can`t rule an isolated severe
storm.

&&

.SHORT TERM /WEDNESDAY THROUGH FRIDAY NIGHT/...
A convective shortwave trough will drop across the Eastern Great
Lakes Wednesday morning, with much needed rain showers across the
region. Ample convergence within an inverted trough and still decent
PWAT values in the 1.5 inch range will allow for downpours of rain
through the morning hours. The better instability will lie across
OH/PA, with a slight to low chance for thunder Wednesday morning.

The inverted surface trough extending northward from the surface low
over the Ohio Valley will begin to retract southward through the
afternoon hours of Wednesday, with our region drying out...though
could still see a few showers down near the state line.

Weak ridging will build slowly over our region as the mean pressure
fields stall as hurricane Erin advances up the eastern coastline
Thursday and Friday...with our region generally dry both days.

&&

.LONG TERM /SATURDAY THROUGH MONDAY/...
A deep trough will drop across the Great Lakes this weekend and into
the start of next week, with a pattern change that will include
possible bands of lake effect rain and cooler temperatures that
will run about 10 degrees below normal.

Initial cold front will cross our region Saturday night. There may
be a few showers across inland Western New York within a pre-frontal
trough, but the bulk of convective showers will come Friday night
along the front.

A few synoptic showers may linger Sunday across eastern zones, with
a dry slot with an afternoon southwest breeze across WNY. As
synoptic moisture returns later Sunday night and into Monday, along
with 850 hPa temperatures dropping down into the single digits a
lake effect rain response may become likely as soon as Monday.
Surface temperatures Monday will struggle to get out of the 60s.

&&

.AVIATION /07Z TUESDAY THROUGH SATURDAY/...
IR satellite shows mostly clear skies across western NY with cirrus
along the southern shore of Lake Ontario to the Eastern Lake Ontario
region this morning. VFR conditions will continue as surface high
pressure remains across the Northeast today. A shortwave trough will
move across the eastern Great Lakes region tonight. Deep moisture
will move into the region with a surface low over far southern
Ontario overnight. Showers, moderate to heavy at times will move
across the region, while flight conditions become MVFR or below.
Isolated to scattered thunderstorms are possible. IFR conditions are
possible across western NY this morning.

Outlook...

Wednesday...Localized cig/vsby restrictions possible especially
early in the day, otherwise mainly VFR with decreasing chances for
showers and thunderstorms.

Thursday and Friday...VFR.

Saturday...Mainly VFR. Low chance of showers.

&&

.MARINE...
Winds will be southeasterly for most of today as high pressure
passes across central Quebec. Winds will become more easterly on
Lake Ontario this afternoon. This will keep higher waves mainly
directed toward Canadian waters during this time frame.

A weak low passes through the region during the mid week period with
a general weak gradient, resulting in lake breeze circulations.

Conditions on the Lower Great Lakes could become choppy again by
Thursday as a northeast flow redevelops, but confidence on the
strength of the flow is low.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...None.
MARINE...None.

&&

$$

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