623
FXUS61 KBUF 121656
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
1256 PM EDT Sat Jul 12 2025

.SYNOPSIS...
Hot and humid today, with a chance of a few afternoon showers or a
thunderstorm during peak heating. A cold front will near the region
on Sunday with widespread showers and thunderstorms, some of which
could produce strong gusty winds and locally heavy rainfall. Drier
weather returns Monday, with somewhat cooler temperatures and less
humidity.

&&

.NEAR TERM /THROUGH TONIGHT/...
Heat and humidity will build this afternoon. We should see mercury
readings reach the mid-upper 80s with low 90s in the Genesee Valley
and the lake plains south of Lake Ontario. Dewpoints are forecast in
the upper 60s to near 70F. This will result in heat indices in the
mid to upper 90s along the lake plains, Genesee Valley, and northern
Finger Lakes. Heat advisories have been hoisted for these areas.
That said...there is one other thing to watch as the heat builds
this afternoon, CAMs show convection firing up again just east of
the Genesee Valley and Finger Lakes region after 19Z.

Otherwise...muggy and mild tonight ahead of the approaching trough
and cold front. There will be a continued chance of showers or a
thunderstorm. Air conditioner will definitely be cranking as temps
will `not` drop very far, with many locales in the low 70s.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
A closed low over James Bay Sunday morning will lift northward while
an upper level trough moves into the eastern Great Lakes region
through Sunday night. A southwest flow between the approaching
trough and an exiting upper level ridge will provide a corridor of
deep moisture across the forecast area Sunday into Sunday night. A
slow moving cold front will approach the forecast area during the
day. Daytime heating and deep moisture with dewpoints in the low 70s
will result in skinny CAPE across the region. Showers and
thunderstorms will develop ahead of the front, with a focused area
of convection ahead of a pre-frontal trough east of the Genesee
River. Forecast PWATS of 2"+ and mean RH% of 75%+ support heavy
rainfall in any convection. 3-hr flash flood guidance 2-2.5" across
the northern Finger Lakes region which may lead to localized flash
flooding if training storms develop. This is aligned with the Day 2
WPC Marginal/Slight Risk for Excessive Rainfall. The wind field is
weak, however there is an uptick in westerly flow to the north which
may help storms further north move but also increase the severe
potential. While there is greater uncertainty in the severe weather
potential, an unstable, moist environment may produce an isolated
downburst. This is aligned with the Day 2 SPC Marginal Risk for most
of the forecast area.

The front will move across the forecast area Sunday night. The
chance for showers and thunderstorms will diminish from west to
east, with heavy rainfall remaining possible across the northern
Finger Lakes into north-central NY Sunday night. Little wind behind
the front may result in fog development for locations that recorded
rainfall and clear out overnight. The main axis of moisture will be
east of the forecast area Monday. Little cold air advection behind
the front, so still warm but less humid Monday. Dry weather will
continue through Monday night.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
Upper level heights will build across the Northeast Tuesday through
Tuesday night. Surface high pressure over the Ohio Valley should
keep us relatively quiet, however warm weather is expected.
Uncertainty increases mid-week as an energetic northern stream moves
south towards the Great Lakes region. Wednesday looks to be a
transition day as the pattern becomes more active heading into the
weekend. Very warm and humid weather is anticipated, with showers
and thunderstorms at times.

&&

.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
VFR for much of the daytime hours, as the heat builds there will be
a renewed chance for a few showers or thunderstorms this afternoon
into the early evening, especially from the Finger Lakes eastward.
Any heavier shower or thunderstorm will again have the possibility
of producing a localized brief period of IFR or below conditions.

Outlook...

Sunday and Sunday night...Showers and thunderstorms likely with
restrictions possible.

Monday and Tuesday...VFR.

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

&&

.MARINE...
Light winds and minimal wave action today, there will be a chance of
an isolated shower or thunderstorm. A slow moving cold front will
bring increasing chances of showers and thunderstorms Sunday through
Sunday night. Winds pick up a bit ahead and with the front but
remain well below any headline criteria.

Winds remain fairly light Sunday night behind the front through
Tuesday as high pressure builds in across the lakes.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...Heat Advisory until 7 PM EDT this evening for NYZ001>006-010-
     011-013-014.
MARINE...None.

&&

$$

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