891
FXUS61 KBUF 151402
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
1002 AM EDT Wed May 15 2024

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

&&

.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
Weak mid level circulation and associated vorticity maxima drifting
across eastern PA today, is producing an area of showers which
are mainly across southcentral NY into central NY. Meanwhile a
weak surface cold front is slowly settling south/southeast of
Lake Ontario across western and northcentral NY. These features
will result in increasing showers and possibly a few
thunderstorms as diurnal instability increases this afternoon.
The best coverage of rain will be from the Southern Tier into
the Finger Lakes with this area spreading north later in the
afternoon. Similar to today, the lowest chance of rain will be
close to Lake Erie and all but far eastern Lake Ontario where
stable lake cooled air lowers instability. Low level
northeasterly flow will aid in lake stabilized air off Lake
Ontario making further inroads which will help limit shower
activity from the Niagara Frontier over to Rochester as well.
Overall flow will again be weak, supporting slow storm motion
with any thunderstorms and the risk for some locally heavy
downpours.

Tonight, lingering showers across inland areas will gradually
diminish and end 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 /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
Drier conditions should take hold Thursday as a mid level low
pushes off the Mid Atlantic coast and ridging starts to build
into the region. Exception may be for areas east of Lake Ontario
and possibly the Finger Lakes, as Atlantic moisture wraps in on
the northern side of the departing low. This may allow for a
few showers or even an isolated thunderstorm to develop as weak
diurnal instability develops. High temperatures mainly in the
upper 60s to lower 70s, but northerly flow will keep the south
shore of Lake Ontario cooler.

Mid level ridge builds into the region Thursday night, any lingering
shower activity will end with a brief dry period for Thursday night.

Mid level ridge departs on Friday with moisture starting to increase
ahead of the next upper trough progressing into the eastern Great
Lakes Friday and Friday night. The associated surface low will lift
to near James Bay Friday night dragging a cold front toward the
region. Warm/moist advection and isentropic ascent ahead of the
front will drive increasing chances for showers from west to
east Friday into Friday night. Some marginal instability will
develop with the potential for some embedded thunder.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
Shower activity continues through most of the long term period. A
trough moving through the area early Saturday will continue the
potential for showers through the morning. As the trough departs to
the east, shower activity will diminish through the day on Saturday.

The potential for showers will continue through the period, but to a
lesser extent then Saturday morning as a few different systems pass
by mainly to the north and south through the rest of the long term
period. A larger trough and mid-level low over the mid-Atlantic will
keep showers in or near the forecast area for much of the forecast
period. The driest day as of now looks like Sunday, but there is
still much variability among the models for the later portion of
the long term and into the new work week.

Temperatures during the period will be mainly above normal with
highs in the low to upper 70s for the lower elevations inland from
the lakes. For the higher terrain and areas closest to the lakes
with onshore winds highs will be in the low 60s to near 70.
Currently, Saturday will be the coolest day of the period, with some
warmer temperatures for Sunday-Tuesday with most of the three days
around the same temperatures for afternoon highs.

&&

.AVIATION /14Z WEDNESDAY THROUGH SUNDAY/...
Low cigs and fog this morning will continue to improve some
through this afternoon, although there may be some lingering
MVFR/IFR stratus throughout the day, especially across the
Western Southern Tier. Patchy fog is also possible.

Showers will again increase in coverage, with the greatest
coverage of rain across inland areas and the lowest coverage
close to Lake Erie and all but far eastern Lake Ontario. A few
thunderstorms may develop again in the afternoon that will have
the potential to produce localized brief reductions in VSBY.

IFR/MVFR CIGS will continue into tonight with fog likely to expand
in coverage through the overnight once again. Lingering showers
across inland areas will taper off through the late evening/early
overnight hours.

Outlook...

Thursday...MVFR/IFR improving to VFR through the morning.
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. Northeast winds in the 10-12 knot range will produce mainly
light chop on Lakes Erie and Ontario through tonight. Otherwise,
light winds will return Thursday as weak high pressure builds over
the eastern Great Lakes. An offshore flow will then develop Thursday
night and Friday with gentle to moderate southeasterly breezes in
advance of the next system approaching from the west.

&&

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

&&

$$

SYNOPSIS...Hitchcock/JM
NEAR TERM...Apffel/Hitchcock/JM
SHORT TERM...TMA
LONG TERM...SW
AVIATION...Apffel/JM
MARINE...JM