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732
FXUS61 KBUF 071742
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
142 PM EDT Fri Jun 7 2024

.SYNOPSIS...
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Cooler today with scattered to numerous showers and some
thunderstorms as an area of low pressure moves through the region.
Shower chances decrease Saturday with a brief period of drier
weather. Unsettle weather returns Saturday night and lasts through
Sunday with chances for showers and some thunderstorms.
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&&

.NEAR TERM /THROUGH SATURDAY/...
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A moist cyclonic flow around a deep mid-level low will continue to
deliver unsettle weather across the Lower Lakes today. As mid-levels
cool aloft, to the tune of +6C to +7C, and the support from
channeled shortwave energy we will continue to see showers and some
thunderstorms through early this evening. In terms of
sunshine...should be fairly limited given the cooler air mass
filtering in aloft. Any amount of sunshine is likely to lead to more
clouds and then additional storms. All this activity is in concert
with the arrival of deeper moisture and the trough axis swinging
into the region. Given the convective nature of the
storms...rainfall amount will vary greatly over any given location,
with up to 0.50 inch in the stronger cells. Otherwise...it will
become breezy with wind gusts up to 35 mph.

Tonight...the mid-level low will slowly churn eastward and heads
towards New England overnight. We should see a general decrease in
shower and storm coverage overall, especially with the loss of
daytime heating. That said...given the cool airmass aloft (+5C/+6C
at H850) there may be some lake induced showers east and southeast
of the lakes. Its marginal but with lakes in the 60s (+16C/17C) it
certainly is enough. The best shot will `likely` be east of Lake
Ontario where deeper synoptic background moisture will be found and
a longer fetch given W-WNW flow.

There will still be some showers east of Lake Ontario early Saturday
morning. After that...weak shortwave ridging gradually builds in
which will bring about a drying trend from west to east by the
afternoon. However...this will be short-lived with the next round of
showers and storms arriving by Saturday night. More on that in the
short-term disco.

Overall not quite as cool Saturday...we should see a decent amount
of sunshine too with highs peaking in the upper 60s to low 70s.
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&&

.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/...
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Saturday night, another seasonably strong mid level closed
circulation will move from northwest Ontario to southern Quebec,
with DPVA and height falls spreading into the eastern Great
Lakes overnight. The forcing from the approaching trough will
combine with a strengthening upper level jet streak rounding the
base of the trough to bring a period of deep layer ascent to
the eastern Great Lakes. Model guidance continues to suggest a
baroclinic wave will peel off of a system over the central High
Plains and partially phase with the incoming trough, producing a
period of widespread showers and a few scattered thunderstorms
Saturday night across much of the region as the baroclinic wave
enhances frontogenesis and deformation.

Sunday through Sunday night, the organized area of rain from
Saturday night will exit early Sunday. Several additional shortwaves
will move trough the mean trough across the Great Lakes and New
England, bringing a few more rounds of at least scattered showers
Sunday through Sunday night. Modest diurnal instability will
contribute to shower chances Sunday, and modest lake instability
and upslope flow will contribute Sunday night. Temperatures will be
on the cool side, with highs in the mid to upper 60s in most
locations.
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&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
The same general longwave pattern will remain in place across North
America through early next week, with an expansive ridge in the west
and a trough in the east. In fact, the trough in the east will reach
its deepest extent on Monday when 850MB temps drop to around +4C
across the eastern Great Lakes. The trough and associated forcing,
deeper moisture, and cool air aloft will continue to support showers
and cool temperatures through Monday night. Weak diurnal instability
will continue to enhance showers by day, with lake instability
enhancing showers by night.

By Tuesday, the trough will begin to deamplify and drift to along or
just off the east coast. Temperatures aloft are still quite cool,
and this may still support a few spotty showers, but with less
coverage than Monday. Tuesday night height rises will spread across
the Ohio Valley and eastern Great Lakes ahead of another trough
digging into the upper Great Lakes. This will bring a brief
interlude of dry weather.

Model guidance begins to diverge by Wednesday and Thursday with the
handling of the next system. The 00Z GFS develops another closed low
over the Ohio Valley and eastern Great Lakes with increasing rain
chances. Meanwhile, the 00Z ECMWF/GEM are much weaker and farther
north with this shortwave energy, keeping a weak open wave moving
through southern Canada. Given the model spread and weak look of the
ECMWF/GEM solutions, kept POPS low for Wednesday, in the 20-30
percent range.

A warming trend will develop by the middle of next week after a few
cool days, with above average temperatures returning.

&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
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A mix of mainly MVFR/VFR conditions are expected today as scattered
to numerous showers and a few thunderstorms develop through this
evening. Any of the stronger cells may bring brief IFR conditions to
area terminals.

VFR conditions are expected this evening through tonight.

Outlook...

Saturday...Mainly VFR. Chance of showers in the morning at KART.
Saturday night...VFR/MVFR with showers and a slight chance of
thunderstorms.
Sunday...Mainly VFR. Chance of showers.
Monday...Mainly VFR. Chance of showers.
Tuesday and Wednesday...VFR conditions.
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&&

.MARINE...
Fresh southwest to west winds expected on both lakes today producing
modest chop. Small craft advisories and beach hazards are in place
on Lake Erie through Saturday. Small crafts on Lake Ontario for the
eastern portion of Lake Ontario today but will likely be expanded
west to cover the entire lake tonight through Saturday.

Winds relax Saturday night, before increasing again Sunday into
early next week. Small Craft Advisories may be needed during this
time.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
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NY...Beach Hazards Statement until 11 PM EDT this evening for
     NYZ010-019-085.
MARINE...Small Craft Advisory until 8 PM EDT this evening for LEZ020.
         Small Craft Advisory until midnight EDT tonight for LEZ040-
         041.
         Small Craft Advisory from 5 PM this afternoon to 2 AM
         EDT Sunday for LOZ044-045.
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&&

$$

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