552
FXUS61 KBUF 020807
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
407 AM EDT Thu May 2 2024

.SYNOPSIS...
High pressure across the western Great Lakes will ridge across the
region, resulting in mainly dry weather through Friday morning.
A series of fronts will then slide across the Great Lakes Friday
night through Sunday bringing the next round of rain showers and
possibly a few rumbles of thunder.

&&

.NEAR TERM /THROUGH TONIGHT/...
A weak surface cold front s in the midst of passing across the
Finger Lakes early this morning, as noted by the wind shift front
southwesterly to northwesterly. As such, associated lift and
moisture ahead of the front has exited the region into the
Adirondacks and central New York, leaving the majority of the region
with just a few high level clouds and predominately dry weather.

Ridging will continue to build east across Western and North-central
New York today. While the shortwave trough aloft responsible for the
surface low passing by well to the north this morning will dive
southeast across New England today, the low should be far enough
northeast, keeping the region on the dry side. Due to the cold
frontal passage early this morning, temperatures today will be a tad
bit cooler today with highs ranging in the upper 50s to low 60s east
of Lake Ontario and in the mid to upper 60s south of Lake Ontario,
with a few locations along the New York and Pennsylvania border
reaching 70.

Surface high pressure will then slide east tonight with the longwave
upper level ridge axis slides across the region. Overall this will
promote continual dry weather with overnight lows ranging in the
40s.

&&

.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
The axis of a mid level ridge will drift east across NY/PA on
Friday, with 850MB temps soaring to +14C by afternoon across Western
NY. This will bring summer-like temperatures to Western NY, with
highs in the upper 70s to lower 80s in most locations. The North
Country will be a little cooler, being farther removed from the
thermal axis over Western NY, with highs in the upper 60s to lower
70s. An ENE flow over Lake Ontario will also keep the south shore of
Lake Ontario much cooler, especially west of Rochester.

Most of Friday will be dry. The ridge axis will begin to drift east
by late afternoon, with height falls and DPVA reaching Western NY by
the end of the afternoon. This will support increasing clouds later
in the day, and a few spotty showers and thunderstorms may develop
by late afternoon across Western NY. This would be most probable
just east of Lake Erie in the typical lake breeze convergence zone
from northwest PA into southwest NY mainly south/southeast of
Buffalo.

Friday night through Saturday night unsettled weather will return to
the region. The mid level trough upstream will drift east into the
eastern Great Lakes and then stall as the downstream pattern
stagnates in response to a closed low over the North Atlantic to the
east of New England. A plume of deep moisture will become situated
across the eastern Great Lakes, with numerous convectively augmented
vorticity maxima drifting through the mean southwest flow across the
region.

The combination of moisture and forcing will bring occasional rounds
of showers Friday night across Western NY, and then the entire
region Saturday through Saturday night. The best chance of thunder
will be on the front side of the system late Friday afternoon and
Friday night when instability is greatest. Cooler temperatures will
then restrict the thunder potential Saturday through Saturday night,
although there may still be a slight chance of a few spotty
thunderstorms if there are enough breaks in the rain and overcast.
The clouds and showers will keep highs in the mid 60s for lower
elevations and around 60 for higher terrain Saturday.

&&

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
Sunday, the mid level trough axis stalled over the eastern Great
Lakes since Friday night will start to make some eastward progress,
and also weaken with time. Lingering weak forcing and moisture will
still support a few rounds of showers, with the greatest coverage
likely to be east of the Genesee Valley.

Surface high pressure and a bubble of drier air will then build into
the Great Lakes Sunday night and Monday, with a return to mainly dry
weather. Model guidance begins to diverge with the timing of the
next system by Tuesday, with the GFS faster in the return of
moisture and forcing while the ECMWF/GEM are slower. Given the
slower trend of the ECMWF/GEM, kept POPs on the lower end of the
chance range.

Rain chances will increase Tuesday night through Wednesday as low
pressure moves into the upper Midwest, with a downstream warm front
moving northeast across the Great Lakes region. Enough instability
may return to support at least a slight chance of thunder by the
middle of next week.

Temperatures will continue to run above average through the period,
with highs in the 60s Sunday and Monday giving way to 70s by Tuesday
and Wednesday.

&&

.AVIATION /08Z THURSDAY THROUGH MONDAY/...
A weak surface cold front is in the midst of passing east across the
region tonight and is currently located across the Finger Lakes as
being denoted by the subtle wind shift from southwesterly to
northwesterly. Cloud cover associated with the front are currently
pushing east into the Adirondacks early this morning, leaving just a
few high level clouds across the area.

A ridge of high pressure will then slide across the region today and
tonight supporting predominately VFR flight conditions.


Outlook...

Friday...Mainly VFR with a chance of afternoon showers and
thunderstorms.
Saturday...MVFR to VFR with showers likely and possible
thunderstorms.
Sunday...Morning showers, otherwise mainly VFR.
Monday...VFR.

&&

.MARINE...
Weak pressure gradients are expected throughout the remainder of the
week into this weekend across the lower Great Lakes supporting winds
to generally remain below 15 knots. While the week will remain
quiet, a few showers and thunderstorms will be possible Friday night
through Sunday.

&&

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

&&

$$

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