829
FXUS61 KBUF 061841
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
241 PM EDT Sat Jul 6 2024

.SYNOPSIS...
High pressure centered over the Ohio valley tonight will drift
northeast across our forecast area Sunday through Monday. This will
assure us of fair dry through the start of the new work week...but
then a slow moving cold front will likely generate some rainfall in
the form of showers and thunderstorms Tuesday into Wednesday.
Meanwhile...temperatures that will be close to normal to end the
weekend will once again well above normal ahead of the cold front.

&&

.NEAR TERM /THROUGH SUNDAY NIGHT/...
Partly to mostly sunny skies will be found throughout much of the
region for the rest of the afternoon...although widely separated
showers and thunderstorms will still be possible along two main
focusing boundaries.

While less active than from this morning... a low level convergence
zone will stretch from about IAG to ROC with a more active lake
breeze boundary that will extend from near JHW northeastward across
the Finger Lakes to Oswego county. There will be plenty of
instability for the convection to work with in this area with 35-
40kts of bulk shear...so its not out of the question that any given
storm could get strong to severe. Otherwise...these are more likely
to just be heavy rainers with localized wind gusts to 40 mph.

Tonight...high pressure centered over the Ohio valley will slowly
drift east and expand across the Lower Great Lakes. After a few
early evening showers/storms across the Srn Tier...the sfc high will
help to promote fair dry weather. While mild...the mins tonight will
be a few degrees lower than those from early this morning as they
will range from the upper 50s across much of the Srn Tier to the
lower 60s most elsewhere.

High pressure over the region Sunday and Sunday night will then
guarantee nice weather to end the weekend. The mercury will
generally top out in the lower 80s on Sunday with mins in the upper
50s (Srn Tier/Lewis co) to lower 60s Sunday night.

&&

.SHORT TERM /MONDAY THROUGH MONDAY NIGHT/...
Monday...the surface ridge will advance to the east with a
southerly return flow aloft developing through the day. Though
dewpoints will begin to creep upwards, they will still remain
fairly comfortable, save for the Finger Lakes/Southeast of Lake
Ontario region where the axis of low level moisture will push
dewpoints into the mid to upper 60s. However the advection of a
warmer airmass (850 hPa temperatures in the mid to upper teens
Celsius) and a fair amount of sunshine will bring afternoon
highs back into the mid 80s to around 90F.

Though Monday should remain dry, the increasing moisture may bring a
shower or two Monday night to the Finger Lakes/Southeast of Lake
Ontario. Monday night will also return back to the mugginess, with
overnight lows in the mid 60s to lower 70s.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
Tuesday and Tuesday night will likely be the most active timeframe
for this period as a mid level trough approaches our region, sending
a plume of deeper moisture across our region that will enhance
showers and thunderstorms Tuesday afternoon and overnight.

The continued northward advection of warmth and moisture out ahead
of this system will send PWATs back up to between 1.5 and 2.0 inches
during Tuesday...and this in tandem with daytime heating and
increasing large-scale ascent will support the likelihood of another
round of showers and thunderstorms...with the best chances for these
likely coming between Tuesday afternoon and evening. Otherwise it
should be very warm and humid again before the convection arrives on
Tuesday...with highs generally ranging through the 80s and surface
dewpoints running between 65 and 70.

Latest model consensus supports the initial trailing cold front from
this system crossing our area Tuesday night...with a weaker
secondary boundary then following suit during Wednesday. Coupled
with broad troughing aloft...this may allow some additional
scattered showers/isolated storms to persist through Wednesday.
Otherwise cooler and more comfortable air will filter back across
our region following the passage of the above cold fronts...with
highs Wednesday pulling back to the upper 70s/lower 80s...and lows
Wednesday night dipping back into the upper 50s to mid 60s.

After that...high pressure looks to build across the region
Thursday...before sliding out across New England on Friday. This
will result in generally dry weather to close out the work week...
with continued comfortable temperatures Thursday/Thursday night
giving way to warmer readings on Friday.

&&

.AVIATION /19Z SATURDAY THROUGH THURSDAY/...
Mainly VFR conditions through the 18z TAF cycle as surface high
pressure slowly builds into the region from the Ohio Valley.

Lake breeze boundaries will allow a few widely scattered showers and
thunderstorms to persist until early this evening. As of about
1730z, a broken line of showers and thunderstorms extending from
roughly KIUA to KSDC will continue to translate eastward. This
activity is not expected to impact any of the TAF sites, though a
few weaker showers west of this boundary may occasionally move
across KIAG, KROC, and KJHW through 21z.

Shower chances and cloud cover diminish quickly after sunset
tonight. Valley fog is expected to develop in the Southern Tier late
which will likely cause vsby reductions at KJHW to IFR or lower.

Any fog will dissipate following sunrise Sunday morning. Dry weather
with some VFR diurnal cumulus expected through the day.

Outlook...

Monday...VFR.
Tuesday...Restrictions possible with showers and thunderstorms
likely.
Wednesday...Restrictions possible with a chance of showers and
thunderstorms.
Thursday...Mainly VFR with a low chance of showers and thunderstorms.

&&

.MARINE...
Winds will pick up today, following the passage of a cold front.
Conditions will approach small craft criteria on Lake Erie today,
with southwesterly winds increasing to 15 to 20 knots at times this
afternoon. Elsewhere winds pick up but will remain below sca
criteria.

High pressure will build over the lower Great Lakes Sunday and into
the start of next week. This will bring a period quiet conditions
through mid week with a weak pressure gradient favoring light winds
and limited waves. The light flow will allow for some local lake
breezes to form each day.

&&

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

&&

$$

SYNOPSIS...RSH
NEAR TERM...RSH
SHORT TERM...Thomas
LONG TERM...JJR/Thomas
AVIATION...PP
MARINE...Apffel/TMA