451
FXUS61 KBUF 130707
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
307 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/...
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 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.

&&

.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 /07Z SUNDAY THROUGH THURSDAY/...
Convection has waned for the time being but we still could see a pop-
up storm early this morning. Otherwise...most area terminals
will see VFR. There may some spots that see fog across the S.
Tier but too `low` of confidence to include in the TAF for KJHW.

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.

Outlook...

Tonight...Showers and thunderstorms with associated
restrictions across the eastern two-thirds of the area
diminishing from west to east...otherwise VFR with some IFR/MVFR
in lower ceilings possible across the interior of the Southern
Tier/North Country overnight.

Monday and Tuesday...VFR.

Wednesday and Thursday...Mainly VFR. A chance of a shower or
thunderstorm.

&&

.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/JJR
MARINE...AR/HSK/JJR/TMA