596
FXUS61 KBUF 080750
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
350 AM EDT Wed May 8 2024

.SYNOPSIS...
A warm front will move across the area this morning, with an area of
showers and a few thunderstorms crossing the area from southwest to
northeast. The showers will exit the eastern Lake Ontario region
this morning. Dry weather will then prevail most of the time for the
rest of today, although a few more showers and thunderstorms are
possible later in the afternoon and evening, especially east of Lake
Ontario. Unsettled weather will then last Thursday through the
weekend with a series of low pressure systems crossing the region.

&&

.NEAR TERM /THROUGH TONIGHT/...
Regional radar shows showers and a few thunderstorms across western
and north central NY this morning. Warm conditions are across the
region with temperatures in the upper 50s to low 60s. In fact, some
places are about 20-25 degrees warmer than 24 hours ago (Tuesday
morning.)

A stacked area of low pressure is across the central Great Lakes
this morning. A warm front extends from Georgian Bay to western NY
with showers and a few thunderstorms along and ahead of the frontal
boundary. A 40kt low level jet across the Ohio Valley with elevated
instability on the warm side of the frontal boundary has allowed
convection to continue into this morning. A plume of moisture is co-
located with the warm front with PWATS around 1.2 inches. This will
produce heavy rainfall within thunderstorms. Fortunately, the storms
are quickly moving so flooding is not a concern. A southwest wind
will increase across Lake Erie and western NY this morning. The
warm, moist airmass across the relatively cold Lake Erie waters may
result in fog moving inland from Lake Erie through mid-morning.

The warm front will move into the Lake Ontario region while a cold
front moves into western NY this morning. This will usher in drier
air and as showers and thunderstorms move into north central NY,
activity will end from west to east across western NY this morning.
The environment is less favorable east of Lake Ontario this morning
so thunderstorm potential should decrease. By early afternoon, the
area of low pressure will move into eastern Ontario and the warm
front will be near the Saint Lawrence Valley. Mostly dry and breezy
conditions will be across the forecast area. In fact, southwest
winds with gusts up to 35 mph are possible across western NY.

A secondary shortwave trough will move across northern NY this
afternoon. Another round of showers and thunderstorms are possible
mainly east of Lake Ontario but also along a convergence zone south
of Lake Ontario. Most of the region will be post-frontal with low
chances of thunderstorms, however greater instability will be just
to the southeast of the forecast area and coupled with a strong wind
field, there may be a few stronger storms across Oswego and Lewis
counties late this afternoon into this evening.

The shortwave trough will move east of the region tonight and
showers and any thunderstorms will diminish and move east of the
region. Dry conditions are expected across the forecast
area overnight.

&&

.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
An elongated mid level trough will remain in place Thursday through
Thursday night from the Canadian Maritimes to the Great Lakes, with
an east-west oriented frontal zone stretching from the Ohio Valley
to the Mid Atlantic. Latest model guidance has continued the
southward trend in the frontal position, with a wave of low pressure
moving east along the boundary now taking a farther south track
Thursday through Thursday night. The farther south track will yield
a much improved forecast for Thursday, with mainly dry weather
expected through at least the first half of the day. Deeper moisture
and frontogenesis will gradually increase from southwest to
northeast as the frontal wave moves across PA, bringing increasing
chances of showers in the afternoon for areas south of Lake Ontario.

Rain chances will continue Thursday night as another wave of low
pressure moves east along the front. The best chance of more
widespread rain will be found from the Southern Tier into Central NY
in closer proximity to deeper moisture and forcing, with rain
chances trending lower for areas close to the Canadian border.

Friday through Friday night, the longwave trough will continue to
carve out over the eastern US as a series of shortwaves dig through
the Great Lakes and New England. DPVA and height falls will maintain
an area of forcing and rain downstream of the trough axis, with a
weak surface low developing in response to the forcing aloft over PA
and the Mid Atlantic. The GFS continues to be the farthest north
with this feature and would produce widespread rain across the
region. The NAM/GEM/ECMWF have all trended farther southeast,
keeping the best chance of organized rain from the Finger Lakes into
Central and Eastern NY, with lower rain chances in our region.
Trended POPS and QPF down for Friday through Friday night,
especially for areas near the Canadian border.

Temperatures will be notably cooler Thursday through Friday as
persistent low level northeast flow funnels cooler air out of
Canada.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
Overall, the pattern will remain unsettled over the weekend through
early next week, although the finer synoptic scale day to day
details remain uncertain. A deep mid level trough from the Great
Lakes to New England over the weekend will gradually deamplify
early next week, although shortwaves will continue to traverse the
US/Canadian border.

Saturday should start mainly dry, with one system moving east off
the New England coast and the next moving through the central Great
Lakes. The upstream shortwave and associated surface low will then
move over or just south of the region Saturday afternoon through
Saturday night, with another round of showers. The trough axis will
gradually move off the New England coast Sunday, with rain chances
trending down from west to east. Temperatures will remain quite cool
over the weekend with clouds and cool temperatures aloft. Highs both
days will reach the 55-60 degree range in most areas.

Monday through Tuesday another shortwave will move from the Great
Lakes into New England, maintaining a chance of a few showers.
Temperatures aloft will start to recover as mid level heights
gradually rise, allowing temperatures to trend to near or a little
above average by Tuesday.

&&

.AVIATION /08Z WEDNESDAY THROUGH SUNDAY/...
An area of showers and a few embedded thunderstorms resides across
western and north central NY this morning. A brief period of IFR
conditions with heavy rain and lightning are the main concerns with
any thunderstorms this morning. Prevailing VFR conditions will
deteriorate to MVFR/IFR this morning as a warm front moves through
the region. The main concern will be lowering ceilings, however fog
may develop on Lake Erie and move onshore by 15z. Confidence is low
to medium that the fog will reach KBUF before winds ramp up
Wednesday morning. Speaking of winds, low level winds will ramp up
prior to surface winds this morning. There is a low potential of low
level wind shear, mainly from KIAG, KBUF to KROC this morning. It
will be short lived and will be monitoring wind profiles.

Flight conditions will improve to VFR from west to east across the
region today. As mentioned above, winds will ramp up and southwest
winds 15-25kts with gusts up to 30kts are possible late this morning
through early this afternoon from KIAG to KROC. Another round of
showers and a few thunderstorms are possible east-southeast of Lake
Ontario this afternoon into the evening. VFR conditions will become
low-end VFR/high-end MVFR at KART during this time.

Outlook...

Wednesday night...VFR/MVFR.

Thursday and Friday...Mainly MVFR. Showers likely and MVFR stratus.

Saturday and Sunday...VFR/MVFR. A chance of showers.

&&

.MARINE...
WSW winds will then increase today, particularly across Lake
Erie...where winds and wave action will be sufficient to support
Small Craft Advisories as outlined below. Elsewhere choppy...but sub-
advisory conditions can be expected.

An increasingly moist airmass crossing the cold lake waters will
likely produce marine layer fog this morning on Lake Erie and Lake
Ontario with visibility restrictions.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...None.
MARINE...Small Craft Advisory from 8 AM this morning to 8 PM EDT this
         evening for LEZ020.
         Small Craft Advisory until 11 PM EDT this evening for
         LEZ040-041.

&&

$$

SYNOPSIS...Apffel/HSK
NEAR TERM...HSK
SHORT TERM...Hitchcock
LONG TERM...Hitchcock
AVIATION...HSK
MARINE...Apffel/HSK/JJR