288
FXUS61 KBUF 141800
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
200 PM EDT Tue May 14 2024

.SYNOPSIS...
Unsettled weather will continue across the area through Wednesday as
a frontal boundary stalls over the eastern Great Lakes, producing
occasional showers and a few scattered thunderstorms. The greatest
coverage of rain will be this afternoon and evening, and again
Wednesday afternoon well inland from the lakes, with lower coverage
of showers close to Lake Erie and Lake Ontario. Weak high pressure
will build into the eastern Great Lakes Thursday with mainly dry
weather before another front brings rain back to the region later
Friday through Saturday.

&&

.NEAR TERM /THROUGH WEDNESDAY NIGHT/...
Visible satellite imagery showing an agitated cumulus field across
the Southern Tier and Finger Lakes early this afternoon, with the
first few scattered showers starting to develop on radar. Modest
diurnal instability, increased moisture pooling, and weak forcing
from a subtle mid level shortwave will continue to support
increasing coverage of showers through the rest of the afternoon,
especially from the Southern Tier through the Genesee Valley, Finger
Lakes, and southern Tug Hill region. There will be enough
instability to support a few widely scattered thunderstorms as well.
PWAT values are not particularly high, in the 1.0-1.25" range, but
storm motion will be slow, with locally heavy rain possible from any
storms that develop. The lowest rain chances will be found across
the Niagara Frontier and northeast of Lake Ontario where stable lake
shadows will reduce instability.

Tonight, showers will gradually decrease in coverage this evening
with the loss of weak diurnal instability. Overnight, a weak mid
level circulation and associated vorticity maxima will drift north
out of PA, while a weak surface cold front gradually moves south out
of southern Ontario into NY, providing an increase in low level
convergence. This will support an area of showers overnight across
the Southern Tier and western Finger Lakes, with a few spotty
showers still possible across the North Country as well. Expect
mainly dry weather overnight close to Lake Erie and Lake Ontario.
Patchy fog will develop overnight, especially in areas which receive
rainfall this afternoon and evening.

Wednesday, the weak mid level circulation over northeast PA in the
morning will consolidate into a mid level closed low near or just
south of NYC by evening. Meanwhile, a weak surface front will
continue to linger over NY through most of the day. Deep moisture
and weak forcing will again combine with modest diurnal instability
to support increasing showers and a few embedded thunderstorms
through the day. The best coverage of rain will start from the
Southern Tier into the Finger Lakes in the morning, then gradually
spread north through the day. Similar to today, the lowest chance of
rain will be close to Lake Erie and Lake Ontario where stable lake
cooled air lowers instability. Flow will again be weak, supporting
slow motion with any thunderstorms and the risk of locally heavy
rainfall.

Wednesday night, showers will gradually diminish and end from
northwest to southeast as high pressure surface and aloft moves from
the Upper Great Lakes into the Lower Great Lakes overnight. Some
patchy fog may develop again, especially in areas that receive
rainfall.

&&

.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
Thursday, a mid level low will be starting the period just off the
Virgina coastline. While most of the precipitation will be centered
near this feature, a stationary boundary drapped across eastern
zones may trigger a few showers. Instability is minor, but still
enough that a few rumbles of thunder are possible. Northeast flow
over Lake Ontario will keep the southern shoreline in the low to mid
60s, otherwise most of the area will make a run at 70F.

As a mid level ridge builds towards our region Thursday night, any
shower activity will quickly fade. Mainly dry for Thursday night.

Friday will become a little more active as a trough approaches the
eastern Great Lakes. Ahead of this trough southwest flow of deeper
moisture will fuel more coverage area to showers and perhaps a
thunderstorm for Friday. Greatest coverage area will likely be
Friday night as the trough of low pressure draws closer to our
region.

Southerly flow Friday will aid in temperatures reaching into the 70s
across the region.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
A mid level trough will bring showers and thunderstorms to our
region Saturday. Model consensus then diverges some as to how
quickly the trough exits east of our region. A faster eastward
progression would bring drier conditions for the second half of the
weekend into the start of the new work week, however if the trough
slows, some showers and scattered thunderstorms could linger into
Sunday and possibly even Monday. With this in mind will have Chc
PoPs in for both days at this point.

Temperatures will be near to a bit above average during this period.

&&

.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
Showers will continue to increase in coverage through the rest of
the afternoon from the Southern Tier through the Genesee Valley and
Finger Lakes to Central NY, with a few isolated to widely scattered
thunderstorms as well. The lowest chance of rain will be found
northeast of Lake Erie and Lake Ontario where stable lake shadows
will reduce instability. VFR will prevail most of the time, with
brief/local CIG/VSBY restrictions in any of the heavier showers.

Tonight, showers will gradually decrease in coverage, although a few
showers may continue overnight from the Southern Tier into the
Finger Lakes and Central NY. A weak cold front will drift south
across the area overnight. The steepening frontal inversion combined
with increasing low level moisture will allow low stratus and patchy
fog to expand, with areas of MVFR/IFR CIGS/VSBY developing.

Wednesday, low stratus will continue much of the day, with areas of
MVFR and local IFR CIGS persisting. Showers will again increase in
coverage, with the greatest coverage of rain across inland areas and
the lowest coverage close to Lake Erie and Lake Ontario. A few
spotty thunderstorms may develop in the afternoon again.

Outlook...

Wednesday night...Showers gradually ending. Areas of MVFR/IFR in low
stratus and patchy fog.

Thursday...VFR.

Friday...VFR. A chance of showers late.

Saturday...Areas of MVFR with showers likely.

Sunday...Mainly VFR with a chance of showers.

&&

.MARINE...
Generally light winds will continue through the remainder of the
week. Winds will become northeast overnight through Wednesday and
increase into the 10-14 knot range on Lake Erie and Lake Ontario,
producing choppy conditions at times. Light winds will return
Thursday as weak high pressure builds over the eastern Great Lakes.

&&

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

&&

$$

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