531
FXUS61 KBUF 150843
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
443 AM EDT Mon Jul 15 2024

.SYNOPSIS...
It will be very warm and humid with an active weather pattern
setting up through the first half of the work week with several
areas of low pressure crossing the region bringing periodic chances
for showers and thunderstorms. A cold front will sweep across the
area midweek with high pressure building in its wake bringing mainly
dry weather along with cooler and much less humid conditions for the
second half of the work week.

&&

.NEAR TERM /THROUGH TONIGHT/...
Mainly quiet through the early morning hours with warm and muggy
conditions across the area.

Regional radar composite show a convectively augmented wave
currently moving east across southern MI/northern IN producing a
swath of associated showers and thunderstorms. Model guidance is
fairly well aligned on this feature and have this wave crossing our
area through the day with the main focus for scattered stronger
storms this afternoon into the evening. In addition, developing lake
breeze boundaries will be an added trigger for convection, helping
to generate some additional scattered showers and thunderstorms.
Vorticity maximum associated with the MCV will move across the area
this afternoon and evening, allowing it to align itself with peak
daytime heating. Bulk shear increases to a modest 30 knots or so.
This combined with ample instability and moisture should be
sufficient to support scattered strong to severe thunderstorms.
Remnant MCVs also have a history of producing severe weather when
crossing our area during the prime heating hours of the day. SPC is
on board as well with much of western and northcentral NY in Slight
Risk, with the main threat being damaging wind gusts. With PWATs up
around 1.75 inches, any storms could produce locally heavy
downpours, although localized flash flooding is not a big concern as
this activity will be moving fairly quickly. Otherwise, the very
warm and humid (dew points upper 60s/low 70s) conditions will
continue today with highs mainly in the mid to upper 80s. With the
growing confidence for convection today, believe apparent
temperatures will remain below heat advisory criteria across the
Genesee Valley and northern Finger Lakes this afternoon.

Convective wave moves east of the area tonight. Can`t rule out a few
scattered showers or an isolated storm overnight, however expect
bulk of the area to remain dry. Late tonight the next convective
wave approaches as it moves over western Lake Erie/northern OH. It
will be another warm and very stick night with lows in the upper 60s
to low 70s.

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
Tuesday, a longwave trough will remain well upstream of the area
over northwest Ontario. A weak low level trough axis will remain
from the Ohio Valley to New England, with its position modulated by
numerous rounds of convection and associated composite outflow.
Another convectively generated vorticity maxima is forecast to move
east along this boundary Tuesday, supporting another round of
showers and thunderstorms crossing the area from west to east.

Latest model guidance suggests a relatively early arrival of this
feature, moving into Western NY in the morning, then Central NY and
the eastern Lake Ontario region by early afternoon. The arrival of
forcing, clouds, and showers early in the diurnal cycle will likely
limit potential instability and brings a great deal of uncertainty
to the severe weather potential. Deep layer shear is not
particularly strong, up to 30 knots, but the MCV will likely bring a
mesoscale region of enhanced low/mid level shear, convergence, and
ascent as it crosses the region. If stronger storms develop in the
presence of this more favorable MCV environment, localized strong
winds would be the primary hazard.

In the wake of the MCV, a few more showers and thunderstorms may
develop along lake breeze driven convergence zones in the afternoon
and evening, mainly from the Southern Tier through the Finger Lakes
and Central NY. Increasing southwest flow off Lake Erie will likely
produce a stable lake shadow northeast of the lake with mainly dry
weather following the morning/midday convection.

It will be very warm and humid again Tuesday, with highs in the low
80s for Western NY and mid to upper 80s from the Genesee Valley into
Central NY. There may be a brief window of mid 90s heat index from
the Genesee Valley into Central NY, but clouds and convection may
keep temperatures a few degrees lower and prevent Heat Advisory
criteria from being reached.

Tuesday night through Wednesday night the longwave trough will
gradually dig through the Great Lakes, ending up in Quebec by
Thursday morning. One or more convectively augmented shortwaves may
cross NY/PA Tuesday night through Wednesday, supporting ongoing
chances of a few showers and thunderstorms at times. The cold front
will cross the region later Wednesday afternoon, with the chance of
showers and thunderstorms then ending from northwest to southeast
late Wednesday through Wednesday night. Drier and less humid air
will arrive later Wednesday night in the wake of the cold front.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
A period of much drier, less humid, and somewhat cooler weather will
arrive Thursday and likely last through next weekend. A strong ridge
will remain centered over the 4-corners and Great Basin late week
through next weekend, with a downstream trough over eastern
Canada, the Great Lakes and New England. The persistent trough will
keep true heat and humidity at bay.

Thursday will be relatively cool by mid summer standards as a pool
of cool air aloft crosses the region, supporting highs in the mid to
upper 70s for lower elevations and lower 70s for higher terrain.
The airmass will quickly modify, with highs around 80 Friday and
then into the low to mid 80s over the weekend for lower elevations.
Humidity will remain tolerable however, with dewpoints in the 50s to
low 60s.

Surface high pressure will remain over the Great Lakes, Ohio Valley,
and New England much of the time Thursday through Sunday with dry
weather prevailing. A weak cold front will move south towards the
area Sunday, but more favorable large scale forcing and moisture
remain north and east of the area.

&&

.AVIATION /09Z MONDAY THROUGH FRIDAY/...
Area of mainly MVFR CIGS has developed early this morning across the
far western NY terminals (KBUF/KIAG/KJHW) as enhanced low level
moisture moves in across these areas in advance of approaching wave.
These CIGS may last for several hours before mixing out this morning.

Otherwise, a convectively augmented shortwave will push across the
region this afternoon and evening with growing confidence for
showers and thunderstorms. Expect brief periods of MVFR/IFR in
heavier showers and storms, with mainly marginal MVFR to low VFR
CIGS otherwise.

Aforementioned wave will move east of the area late in the day/early
evening with a return to predominantly VFR conditions through this
evening.

Outlook...

Tuesday and Tuesday night...VFR/MVFR with scattered to numerous
showers and thunderstorms.
Wednesday...VFR/MVFR with a chance of showers and thunderstorms.
Thursday and Friday...VFR.

&&

.MARINE...
Southwest winds will remain in the 10-15 knot range today. This will
produce light to at times moderate chop on both Lakes. Southwest
flow will increase further late tonight through Tuesday, producing
more notable chop on both Lakes, with possibly a brief period of
Small Craft Advisory conditions on Lake Erie Tuesday.

There will be periodic chances for thunderstorms across eastern Lake
Erie and Lake Ontario through Wednesday, with the potential for
locally higher winds and waves in and near any storms.

&&

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

&&

$$

SYNOPSIS...JM
NEAR TERM...JM
SHORT TERM...Hitchcock
LONG TERM...Hitchcock
AVIATION...JM
MARINE...JM