303
FXUS61 KBUF 171822
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
222 PM EDT Thu Jul 17 2025

.SYNOPSIS...
Low pressure over southern Quebec will continue to track northeast
tonight, sending a cold front across the region. A few showers
and thunderstorms will be possible with the front through this
evening. Behind the front, cooler and notably drier air will
arrive for Friday. A surface wave and cold front will bring
another round of scattered to numerous showers and thunderstorms
Saturday, which may linger into Sunday. High pressure will
bring dry conditions by early next week.

&&

.NEAR TERM /THROUGH FRIDAY NIGHT/...
Prefrontal trough/initial cold front bringing a line of gusty
showers to the eastern lake Ontario region this afternoon.
Secondary/main cold front across western Lake Ontario will cross
the region through early evening and produce a few more
scattered showers and storms, mainly east of Lake Ontario and
the Saint Lawrence Valley, while drier air aloft should help to
maintain mainly dry conditions across western New York.

Elevated winds will continue this afternoon before dropping
this evening.

Canadian high pressure will build into the region Friday and Friday
night guaranteeing dry and cooler weather. High temperatures in the
70s with overnight lows in the 50s, with some 40s across the
Tug and Western Dacks.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
Quasi-zonal mid-level flow set up across the Great Lakes Saturday
morning will gradually give way to a trough digging south across
eastern Ontario and Quebec through Sunday. As such, surface high
pressure that was overhead Friday will move offshore Saturday as a
convectively enhanced shortwave and associated surface low moves
east from the central Great Lakes/Ohio Valley. Not only will this
pattern support heat and humidity to advect into the area, a few
scattered to numerous showers and thunderstorms will be possible
Saturday afternoon and evening. There is some potential for stronger
convection in this timeframe as deep layer shear increases to around
40kts, though the timing of the main shortwave and consequently the
amount of instability remains a bit uncertain. At this juncture this
potential appears to be greatest across the Southern Tier and
southern/central Finger Lakes region.

Some measure of shower/thunderstorm activity will likely linger late
Saturday night into Sunday morning as the system`s main surface cold
front moves through the region. Drier and more comfortable weather
will inevitably make a return as high pressure builds back into the
region from the upper Great Lakes.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
Exiting mid-level troughing will support a mid-level ridge to build
across the central and eastern Great Lakes Monday and Tuesday before
zonal flow sets up mid-week. As such surface high pressure will
slide east across the central Great Lakes Monday and off the New
England coastline Tuesday, which will result in a period of dry
weather through at least the first half of Tuesday. A potential
shortwave trough gliding through the zonal flow, may support some
showers and thunderstorms Tuesday afternoon through Thursday. The
NBM appears more pessimistic compared to other long range ensembles
and thus could see the forecast trending drier, though there remains
plenty of uncertainty at this range to leave NBM`s sChc/Chc PoPs in
place for now.

Regardless of precipitation chances, the offshore deep anticyclonic
flow will cause the heat and humidity to return, especially by
midweek when some areas across the Lake Plains and Genesee Valley
could reach the low 90s.

&&

.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
Pre-frontal trough will bring a period of gusty showers to the
eastern Lake Ontario region this afternoon with the bulk of
this convection shifting east of KART by 19z. Main cold front
will cross the region late this afternoon/early evening. Highest
confidence of any associated storms will be across the Saint
Lawrence Valley and eastern Lake Ontario region.

Winds will quickly drop off this evening behind the main cold
front. Developing north-northwesterly upslope flow will result
in the development of another period of fairly MVFR ceilings,
with some limited IFR possible across the higher terrain.
Gradual improvement to VFR from north to south will then
overspread the lower elevations overnight.

Outlook...

Friday...Improvement to VFR areawide.

Friday night...Mainly VFR with localized IFR possible in valley fog.

Saturday...Mainly VFR with a chance of showers and thunderstorms and
associated brief restrictions.

Sunday...Mainly VFR.

Monday and Tuesday...VFR.

&&

.MARINE...
Main cold front will cross early this evening with winds becoming
north-northwest and slacken following its passage. Solid Small Craft
Advisory conditions are expected on both lakes into tonight, but
calmer conditions will return Friday as high pressure builds
across the region.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...Beach Hazards Statement through late tonight for NYZ001-002-
     007.
     Beach Hazards Statement through late tonight for NYZ003>005.
     Beach Hazards Statement through late tonight for NYZ006.
     Beach Hazards Statement until 8 PM EDT this evening for NYZ010.
     Beach Hazards Statement until 10 PM EDT this evening for
     NYZ019-085.
MARINE...Small Craft Advisory until 10 PM EDT this evening for LEZ020-
         040-041.
         Small Craft Advisory until 4 AM EDT Friday for LOZ042.
         Small Craft Advisory until 8 AM EDT Friday for LOZ043>045.

&&

$$

SYNOPSIS...TMA
NEAR TERM...TMA
SHORT TERM...EAJ/PP
LONG TERM...EAJ/PP
AVIATION...TMA
MARINE...TMA