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523
FXUS61 KBUF 061022
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
622 AM EDT Mon May 6 2024

.SYNOPSIS...
A cold front will exit the eastern Lake Ontario region this morning,
with showers coming to an end. Early morning fog and low clouds will
give way to partly sunny skies today as high pressure builds into
the region. Dry weather will last through Tuesday before a warm
front crosses the region Tuesday night through early Wednesday with
a chance of showers and thunderstorms. Unsettled weather will then
last the rest of the week as a trough of low pressure slowly crosses
the Great Lakes.

&&

.NEAR TERM /THROUGH TONIGHT/...
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A cold front will move east of the area by mid morning. An area of
showers that was east of Lake Ontario has moved off into the
Adirondacks. A few more spotty light showers are possible through
the early morning east of Lake Ontario and across the western Finger
Lakes, otherwise dry weather will prevail. Much of the fog from
earlier has already dissipated as a drier airmass moves into the
area. The remaining areas of fog across the Southern Tier and east
of Lake Ontario will dissipate by mid morning.

Once the rest of the fog and low stratus dissipates, high pressure
building into the Great Lakes will bring a return to dry weather. A
fair amount of cirrus will stream across the region today downstream
of a mid level trough drifting east across the Ohio Valley. This
will yield partly sunny skies in most areas today as sunshine
filters through the high clouds. Temperatures will continue to run a
little above average, with highs in the 65-70 degree range. Light
northwest flow will keep the southern and eastern shores of Lake
Ontario much cooler.

Tonight high pressure will drift east from the Great Lakes into
Ontario and Quebec, maintaining dry and quiet weather across our
region. Extensive cirrus in the evening will clear overnight. The
mainly clear skies and light winds will allow for strong radiational
cooling, with lows in the low to mid 40s in most areas.
-- End Changed Discussion --

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
Tuesday, a weakening ridge and an elongated sfc high stretching into
the region from Canada will provide for mainly fair weather for the
day. A few scattered showers/sprinkles may reach far sw NY by the
late afternoon. Above normal temperatures will continue with
afternoon highs reaching the low to upper 70s for most areas, except
the higher terrain east of Lake Ontario where afternoon temperatures
will reach the mid 60s.

Tuesday night, a few different weak sfc lows and shortwave troughs
will traverse along a weakening occluded front that is tracking east
across the Great Lakes and Ohio Valley by this time. As these
features track toward the region Tuesday night, shower potential
will increase from southwest to northeast through the night across
the entire forecast area. A few embedded thunderstorms will also be
possible with these showers as there will be some instability,
mainly south of I90. This scenario is similar in some ways to the
setup earlier this past weekend with an occluded front and the
models bringing in more rain than what occurred. Models are starting
to come in a little drier overall for the Tuesday night into
Wednesday time frame, so will need to keep an eye on how the models
handle things. Showers should mostly be done by around daybreak for
the western third of the forecast area, with increasing shower
potential toward the east during the a.m. commute.

Wednesday, showers will linger through most of the morning for the
eastern Lake Ontario area before tracking east, and out of the area.
Wednesday is starting to look a little drier for most areas during
the day with WNY remaining mostly rain free and the eastern half of
the forecast area only having a few scattered showers/sprinkles
during the afternoon. A bit cooler for the day with highs in the low
60s for the higher terrain east of Lake Ontario to the mid 70s for
the lower elevations south of I90.

Wednesday night, shower potential increases later in the night as an
area of low pressure develops over the mid-Mississippi Valley ahead
of a trough and tracks toward the region. Showers will track once
again from southwest to northeast through the second half of the
night. Some guidance is pushing better organized shower activity
farther south and across Pennsylvania, so will need to see how that
evolves.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
The sfc low from Wednesday night will continue to strengthen and
increase in size as a trough amplifies over the central CONUS and as
a few rounds of vorticity advection move through the trough.

As the trough moves east and the main sfc low tracks ahead of it, a
mid level low will develop over the eastern Great Lakes. The
combination of the sfc & mid-level low will cause showers to cover
most of the forecast area for Thursday into Friday. Showers will
mostly taper off from west to east late Friday afternoon into the
night as the sfc low tracks east. However, some lingering showers
will be possible Saturday morning, especially east of Rochester with
a cyclonic flow lingering over the northeast. An incoming ridge for
later Saturday will eliminate any remaining showers that may exist
across the area.

Another trough dropping southeast out of Canada and across the Great
Lakes will increase the shower potential starting Saturday night,
BUT there is still very much uncertainty among the models as to
track and timing of showers associated with the system. Currently
going with chance for showers for most of Sunday, but that can
certainly change either way.

Temperatures for the long term period will generally be near normal
for most of the period, except for Friday, which still looks cooler
than normal.

&&

.AVIATION /12Z MONDAY THROUGH FRIDAY/...
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A cold front will exit the eastern Lake Ontario region by mid
morning, with any remaining spotty light showers mainly east of Lake
Ontario coming to an end.

Much of the fog and low stratus from overnight is already improving
as a drier airmass moves into the area. Areas of IFR VSBY/CIGS over
the Southern Tier and east of Lake Ontario will improve to VFR by
mid morning. Elsewhere, areas of MVFR CIGS will also improve by mid
morning.

VFR will then prevail for the rest of today and tonight with areas
of cirrus.

Outlook...

Tuesday...VFR.

Tuesday night and Wednesday...VFR/MVFR. A chance of showers and
thunderstorms.

Thursday...VFR/MVFR. Showers likely with a chance of thunderstorms.

Friday...MVFR. Showers likely.
-- End Changed Discussion --

&&

.MARINE...
Negligible winds and waves will continue through Wednesday. There
will be some marine layer fog over Lake Erie and Lake Ontario
through early to mid morning as a warm/moist airmass overlays the
cold lake waters. A much drier airmass will move into the area
today, ending the marine layer fog.

&&

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

&&

$$

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