599
FXUS61 KBUF 040529
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
129 AM EDT Tue Jun 4 2024

.SYNOPSIS...
Fair dry weather will be found throughout the vast majority of the
region through at least Tuesday night, as weak high pressure across
our region drifts to the New England coast. It will become quite
unsettled later Wednesday through Thursday with showers and
thunderstorms. Meanwhile, the warm humid weather will give way to
noticeably cooler conditions for the latter portion of the week.

&&

.NEAR TERM /THROUGH TUESDAY NIGHT/...
A well amplified upper level ridge will be parked over the
Lower Great Lakes through Tuesday night, while the associated
area of sfc high pressure will move to the New England coast.
This scenario will keep general subsidence over the region with
only a slight chance for a shower Tuesday afternoon away from
the lakes. With light winds and narrowing dewpoint depressions,
some fog should also redevelop overnight, particularly across
the western Southern Tier and interior portions of the Finger
Lakes.

Meanwhile temperatures will be above normal...particularly Tuesday
into mid week when the mercury will be solidly 10 degrees above
early June standards.

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
Wednesday will mark the start of unsettled weather that will
last into the weekend. The next upper level trough will pivot
east across the Great Lakes Wednesday, allowing for a shortwave
trough with multiple areas of vorticity to pass across the
region through Wednesday night. As such a warm front will advect
in deeper moisture from the Gulf States causing precipitable
water values to peak towards 1.75 inches. Due to the multiple
waves of vorticity, expect multiple rounds of showers and
thunderstorms, first with the passing of the warm front and then
an additional line of storms late Wednesday.

Expect mainly thunder chances through Wednesday and Wednesday night
as MUCAPE values will average between 1000 and 1500 J/kg. Preventing
these storms from becoming severe are the limited 0-6 km bulk shear
values of 25-30 knots, however these values are also supporting
storms to keep on moving through and therefore don`t expect flash
flooding to be an issue.

By Thursday, another round of showers and thunderstorms will be
possible with the passage of the cold front. While the environment
will be bountiful with moisture the severe parameters will be to the
east of the area. Overall expect heavy downpours to be the main
concern and don`t expect these storms to become severe.

In the wake of the front, a closing upper level low will rotate
south towards the eastern Great Lakes. With the moist cyclonic flow
overhead the renewed chances for showers will continue Thursday
night, through with the deeper axis of moisture now outside of the
region, showers will be on the lighter side.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
Our weather will be dominated by a cool/moist cyclonic flow aloft
through the entire period. This will come in the form of a large
upper trough that will dominate the eastern third of the CONUS and
far western Atlantic basin. Within this large upper trough an upper
low is expected to close off and wobble about somewhere within the
bounds this trough. As is typical, long range model guidance
continues to struggle with a consensus on evolution and placement of
said feature, although at this point appears that it will most
likely be oscillating somewhere over the Northeast or Mid Atlantic
region.

In terms of sensible weather, not only will this keep daytime highs
at least a bit on the cooler side of average, but will also keep our
weather unsettled overall. Peak of any daily shower/storm activity
will reside during the afternoon/early evening hours when strong
surface heating and the persistent cool/moist cyclonic flow combine
to maximize instability. Highest concentration for showers/storms
will be along and inland of diurnally/mechanically driven lake
breeze circulations. Add to this the presence of smaller scale
embedded areas of shortwave energy consistently rotating about the
periphery of the upper low that will only enhance precipitation
chances, timing and placement of these features in relation to the
positioning of the upper low will be critical to the forecast. All
this said, in between these smaller scale features there will be dry
time built in, especially off peak heating hours. Stay tuned.

As alluded to above, daytime highs will likely remain at least a bit
below normal through the period overall. This will translate to
highs averaging in the upper 60s to low 70s. Being that we are now
well into June, if more insolation is seen over some portions of the
region during the afternoon hours, temperatures locally could easily
exceed expectations.

&&

.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
Weak high pressure draped across our region will slowly drift east
to the New England coastline overnight through Tuesday. This will
provide our region with predominantly VFR conditions...save for
later tonight into early Tuesday morning when redeveloping fog will
bring localized MVFR to IFR conditions. The lowest conditions will
most likely to be found across interior portions of the Southern
Tier and Finger Lakes.

Outlook...

Wednesday...Mainly VFR with some showers and thunderstorms,
especially over the far western counties during the afternoon.
Wednesday night and Thursday...Areas of MVFR with showers and
thunderstorms likely.
Friday and Saturday...VFR/MVFR with showers and thunderstorms likely.

&&

.MARINE...
A weak pressure gradient will continue to maintain light to modest
winds and minimal waves into midweek.

A cold front will cross the eastern Great Lakes Wednesday night and
Thursday with a few rounds of thunderstorms likely. West to
southwest winds will increase on the lakes behind the cold front
Thursday through Friday with choppy conditions developing.

&&

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

&&

$$

SYNOPSIS...JJR/RSH/TMA
NEAR TERM...JJR/RSH
SHORT TERM...EAJ
LONG TERM...JM
AVIATION...JJR/RSH
MARINE...AR/Apffel/JJR