276
FXUS61 KBUF 131812
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
212 PM EDT Sun Jul 13 2025

.SYNOPSIS...
An approaching cold front will generate widespread showers and
thunderstorms through this evening, some of which could produce
strong gusty winds and locally heavy rainfall. In the wake of
the front, drier weather will return along with less humidity.
More heat expected by mid week.

&&

.NEAR TERM /THROUGH MONDAY/...
A very warm and humid airmass resides across the eastern Great Lakes
region this afternoon. An upper level trough over northern Ontario
will move east-northeast help push a cold front into the region.
High moisture content across the region along with strong daytime
heating with dewpoints in the lower 70s resulting in MLCAPE to near
2000 J/kg. Convection increasing quickly along with Lake Erie lake
breeze and ahead of a pre-frontal trough across the Finger
Lakes into the North Country. The deep moisture fields with
precipitable water values in excess of 2 inches will support the
potential for very heavy rain, with the potential for rainfall
rates in excess of 2" per hour, within the heaviest convective
cells. 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
become problematic with slow moving and possible training
storms bringing the elevated risk of localized flash flooding. A
Flood Watch remains in effect for these areas through 5 AM
Monday. Severe risk is also present, despite a relatively weak
shear environment increasing instability and high moisture content
will support the threat for wet microbursts and isolated wind
damaging storms through this evening.

Instability will wane into the evening hours and so will the severe
threat. Training showers and storms could continue through the early
part of tonight with the flash flood threat continuing. Elsewhere,
deep moisture will be present as the cold front slowly works through
the region with showers continuing to be 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. Humidity levels will lower behind the frontal passage.

&&

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
Primarily zonal mid-level flow across the central to eastern Great
Lakes Monday night will build into a ridge as the next trough dives
south out of the Canadian Rockies and into the northern Plains
Tuesday and into Wednesday. As such, building heights and surface
high pressure will result in drier weather Monday night through
Tuesday night.

A quick paced shortwave trough traveling northeast (across the
central and eastern Great Lakes) within the exit region of the
aforementioned longwave trough Wednesday and Wednesday night will
not only continue to support ample moisture and warmth to advect
northward but also support a weak surface low to pass across the
Great Lakes, supporting increasing chances for showers and
thunderstorms. Additionally as alluded to previously, hot and humid
conditions will be present Wednesday and may warrant heat headlines.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
Longwave troughing will be in the midst of crossing the central and
eastern Great Lakes Thursday and Friday before zonal flow returns
for the weekend.

Passage of a shortwave trough and corresponding warm front Thursday
combined with a warm muggy airmass in place will support showers and
thunderstorms to spark. To follow the warm front, a cold front will
pass across the area late Thursday night through Friday continuing
the chances for showers and thunderstorms.

Aforementioned zonal flow will support surface high pressure to
settle in across the Great Lakes for the weekend. However, long
range guidance continues to flip-flop with the pattern and therefore
confidence continues to remain low for a completely dry weekend.
This being said, the forecast resembles a slight chance for a shower
and afternoon thunderstorm with temperatures rebounding back towards
normal with highs in the low 80s.

&&

.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
A slow-moving cold front will approach our region through this
evening. Coverage of showers and thunderstorms will continue to
increase through this evening (some with locally heavy rainfall
and strong gusty winds). 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 through Friday...Restrictions possible in scattered
mainly afternoon showers and thunderstorms.

&&

.MARINE...
A slow moving cold front will then bring increasing chances of
showers and thunderstorms through tonight. Special Marine Warnings
may be needed for locally strong winds. 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 through late tonight for NYZ003>006-008-013-014-
     021.
MARINE...None.

&&

$$

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