966
FXUS61 KBUF 170657
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
257 AM EDT Tue Jun 17 2025

.SYNOPSIS...
A warm front will lift northward across our region today, bringing
humid conditions for Western New York, along with chances for
showers and thunderstorms. A few heavier thunderstorms across the
Southern Tier will bring a drenching downpour. A more active period
for storms will occur Wednesday and Thursday ahead of a cold front
that will pass across the region Thursday.

&&

.NEAR TERM /THROUGH TONIGHT/...
A warm front will lift across WNY today leaving a humid airmass in
place across Western New York. This moisture, coupled with daytime
heating and the passing of a convective shortwave trough will bring
blossoming showers and thunderstorms this afternoon and evening.

There is not a lot of wind shear, so storms should not build to
great heights...with just garden variety storms for the region this
afternoon and into the evening hours. Heavier downpours will be
possible for the southern two tier of counties of WNY where the
better lift ahead of the shortwave trough intersects the axis of
deeper moisture.

Convection will taper down through the evening with the loss of
daytime instability, weakening lake breeze circulations and also the
exit of the shortwave trough. However a lingering frontal boundary
within ample supply of low level moisture will allow for a few spot
showers through the night, especially from the Southern Tier
northeastward across the Finger Lakes and eastern Lake Ontario
region.

Some patches of fog are likely to form tonight, especially in areas
that received a shower today...increasing the near ground moisture
content.

&&

.SHORT TERM /WEDNESDAY THROUGH FRIDAY NIGHT/...

The phasing of shortwaves will support a deeper longwave trough
to carve out across the Great Lakes and result in a
strengthening surface wave of low pressure. As this feature
lifts northeast from the Upper Midwest to Quebec, a pair of
fronts will slide across the area Wednesday through Thursday.
Initially a warm front will lift north across the area Wednesday
afternoon, supporting a warm humid airmass to advect across the
area. The combination of strong diurnal heating and ample
moisture will produce scattered showers and storms. Then, a
strong southwesterly low level jet will move into the area,
along with a prefrontal trough and eventual cold front late
Wednesday night into Thursday morning, renewing the potential
for showers and thunderstorms. The combination of PWAT values
around 1.75 inches (amounts well over 90% of the daily mean) and
a wind direction parallel to the front, would support heavy
rainfall, as supported by WPC`s Day 4 marginal risk for
excessive rainfall. In regards for severe thunderstorms, the
better low level lapse rates, and shear will lie across the
northern Finer Lakes eastward, and therefore a few stronger
storms can`t be ruled out.

While convection will gradually diminish Thursday night a few
showers may linger across the area through Friday as the longwave
trough axis crosses the area. Additionally, cooler air will advect
across the area in the wake of the trough axis Friday/Friday night.

&&

.LONG TERM /SATURDAY THROUGH MONDAY/...
The next stout upper level ridge will slide across the Gulf States
Saturday before amplifying northeastward Sunday and into the start
of the next work week. This upper level feature will bring steady
increasing heat and humidity into the region for the weekend and
into the start of new work week. However, an ill-timed shortwave
ridge-runner will support the possibility for a few rounds of
showers and thunderstorms Saturday through Sunday before surface
high pressure then dominates overhead for Monday. As alluded to
previously, the combination of 500 mb heights building to near 600dm
over the Ohio Valley and lower Great Lakes would support very hot
and humid conditions with heat index values climbing well into the
90s by Monday.

&&

.AVIATION /07Z TUESDAY THROUGH SATURDAY/...
For the 06Z TAFS a warm front lifting northward into our region will
bring an increase in low level moisture, maintaining IFR ceiling
heights for the Southern Tier (KJHW) and lowering ceiling heights
for KBUF/KIAG and KROC to MVFR in the 12 to 18Z timeframe. MVFR
ceiling heights east of Lake Ontario (KART) should prevail through
the morning hours.

Chances for showers and a few thunderstorms will increase this
afternoon as a convective shortwave trough passes through. The best
chances for thunderstorms will occur across the Southern Tier and
Upper Genesee Valley. Ceiling heights may improve briefly to VFR
this afternoon and early evening, especially for the lake plain,
before settling back to lower terrain MVFR and higher terrain IFR
for tonight. Some patches of fog are likely to form tonight,
especially in areas that received a shower today...increasing the
near ground moisture content.

Outlook...

Wednesday and Thursday...VFR/MVFR with showers and thunderstorms
likely.

Friday...Mainly VFR. A chance of showers and thunderstorms,
mainly east of KROC.

Saturday...Mainly VFR. Increasing chances for showers and
thunderstorms.

&&

.MARINE...
Light southeast to southerly flow today as a stable regime of cool
lakes and warm inland temperatures sets up. This flow will become
slightly stronger and more defined tonight as the airmass cools and
lake breeze circulations weaken. The wind flow will become more
southwesterly tomorrow, but wind speeds will likely remain below
small craft advisory criteria.

By Thursday, a cold front will be drawing upon our region and a
tightening pressure gradient ahead of the front will allow for
southwest winds to increase to possible SCA criteria on both lakes.
This flow will also increase the waves on the lakes especially the
eastern half of Lake Ontario by Thursday evening where waves may
breach the 4-foot mark.

&&

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

&&

$$

SYNOPSIS...Thomas
NEAR TERM...Thomas
SHORT TERM...EAJ
LONG TERM...EAJ
AVIATION...Thomas
MARINE...Thomas