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205
FXUS61 KBUF 131034
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
634 AM EDT Sun Jul 13 2025

.SYNOPSIS...
A cold front will approach the area today...and in the process will
generate widespread showers and thunderstorms, some of which could
produce strong gusty winds and locally heavy rainfall. In the wake
of the front drier weather will return on Monday night, along with
less humidity.

&&

.NEAR TERM /THROUGH MONDAY/...
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A very warm and humid airmass resides across the eastern Great Lakes
region today. An upper level trough over northern Ontario will move
east-northeast while an upper level ridge persists off the east
coast. Water vapor satellite products show a shortwave trough
over Ohio, and Gulf and Atlantic moisture converging across the
region this morning. A cold front will slowly approach the
forecast area through this evening. Daytime heating and deep
moisture with dewpoints in the low 70s will result in 1500-2000
J/kg of CAPE across the region today. Showers and thunderstorms
will develop ahead of the front, with a focused area of
convection along a pre-frontal trough east of the Genesee River.
Forecast PWATS of 2"+ and mean RH% of 80%+ will support heavy
rain in any convection. Upwind propagation vectors are forecast
to remain weak across the region and training storms are
possible. 1-hr FFG of 1.5-2.5" and 3-hr FFG of 2-2.5" extends
from Allegany county to the northern Finger Lakes region which
could result in localized flash flooding if training storms
develop. FFG is slightly higher across Oswego and Lewis county,
however ingredients are there for training storms. A Flood Watch
is in effect for the areas mentioned from 11 AM today through 5
AM Monday. Shear is rather modest with 20-25kts of 0- 6km bulk
shear, but coupled with a very moist environment may result in
an isolated severe storm across most of the forecast area today.
Temperatures will again reach the mid to upper 80s across the
lake plains and Genesee Valley today. The combination of
humidity and warm temperatures may result in heat indices in the
upper 90s, however confidence is much lower than yesterday
because of cloud cover and rain in the area. Opted out of
issuing a Heat Advisory.

Instability will wane into the evening hours and so will the severe
threat. Training showers and storms may be ongoing and the flash
flood threat will continue through the evening hours. Elsewhere,
deep moisture will be present as the cold front trudges through the
region and showers are possible overnight.

The upper level trough axis will move through the region with the
cold front finally exiting the eastern edge of the forecast area
Monday. There remains a corridor of deep moisture from the Ohio
Valley into New England, which keeps the chance for showers and
thunderstorms across interior portions of the forecast area. A
convergence zone may develop along the lake plains south of Lake
Ontario and there is a low chance of showers developing by
afternoon. Warm weather will continue however dewpoints will be
lower.
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&&

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
Building heights and surface high pressure will bring drier weather
Monday night through Tuesday night.

A fast moving shortwave trough will move from the northern Rockies
to the Upper Great Lakes Wednesday into Thursday. Moisture and
warmth will stream northward while a surface low moves across the
Great Lakes region. Wednesday will be a transition day with
increasing chances for showers and thunderstorms. Hot and humid
conditions may warrant heat headlines beginning Wednesday.

&&

.LONG TERM /THURSDAY THROUGH SATURDAY/...
A humid (Mean PWATS 1.75") and a very warm airmass (surface
temperatures in the 80s) Thursday will be accompanied with showers
and thunderstorms upon a warm front...with additional lift for storm
development supported by the passage of a mid level shortwave
trough.

Chances for showers and thunderstorms continue Thursday night
through Friday with the approach and passage of a cold front.

Surface high pressure and mostly zonal flow is possible across the
region this weekend. There has been some flip-flopping with guidance
for the weekend so confidence is low that it will be quiet and dry.
That being said, post-frontal conditions should result in
temperatures approaching normal (low 80s.)

&&

.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
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Convection is increasing in coverage this morning. Most area
terminals are VFR, however brief periods of MVFR/IFR are
possible in any showers or storms.

A slow-moving cold front will approach our region today and
trigger the development of fairly widespread showers and
thunderstorms (some with locally heavy rainfall) between the
late morning and afternoon hours. These may produce
brief/localized reductions (mainly in visibility) to MVFR or
even IFR...with VFR conditions otherwise prevailing.

Showers and storms are possible through tonight which may cause
flight restrictions at TAF sites, especially at KROC and KART.
Low-level moisture will pool across the region and stratus is
possible across interior Southern Tier and North Country late
tonight.

Outlook...

Monday and Tuesday...VFR.

Wednesday and Thursday...Mainly VFR. A chance of a shower or
thunderstorm.
-- End Changed Discussion --

&&

.MARINE...
A slow moving cold front will then bring increasing chances of
showers and thunderstorms through tonight. Winds will pick up a bit
ahead and with the front, but will still remain well below any
headline criteria.

Behind the front...winds will be fairly light tonight through
Tuesday as high pressure builds in across the lakes.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...Flood Watch from 11 AM EDT this morning through late tonight
     for NYZ003>006-008-013-014-021.
MARINE...None.

&&

$$

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