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865
FXUS61 KBUF 110725
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
325 AM EDT Tue Jun 11 2024

.SYNOPSIS...
Extensive cloud cover will continue much of today. There may be some
patchy drizzle this morning, then a few isolated showers this
afternoon, but most of the time will be rain free. High pressure
will bring a return to dry weather tonight, with dry weather lasting
Wednesday through most of Thursday. Today will still be cool, but
this will be followed by a notable warming trend through the middle
of the week. A cold front will bring another round of showers and
scattered thunderstorms Thursday night through a portion of Friday.

&&

.NEAR TERM /THROUGH TONIGHT/...
Widespread low stratus will persist this morning across the entire
region. Radar imagery continues to show some weak returns, likely
marking some patchy light drizzle falling from the low overcast.

A deep mid level trough will continue to move slowly east across New
England today through tonight. Moist cyclonic flow on the western
flank of the trough will persist across the eastern Great Lakes
today. The moist northwest flow, enhanced by some lake induced
instability and upslope flow, will continue to produce a wealth of
low clouds through at least the first half of today. The clouds will
start to gradually scatter out later this afternoon, first over and
near Lake Erie and Lake Ontario. The clearing will gradually
progress into the higher terrain of inland areas this evening.

Patchy drizzle will continue in some areas this morning. This
afternoon will be mostly dry, although a few isolated showers are
still possible across the higher terrain of the Southern Tier,
Finger Lakes, and east of Lake Ontario from persistent upslope flow
and modest steepening of low level lapse rates with daytime heating.

High pressure will build over the eastern Great Lakes and Ohio
Valley tonight, supporting the ongoing clearing trend. Expect some
patchy fog overnight, primarily in the Southern Tier valleys.

Temperatures will remain cool. Highs today will range from the mid
60s across lower elevations to around 60 for higher terrain. Lows
tonight will drop back into the 40s across inland areas, with lower
50s along the lakeshores.

&&

.SHORT TERM /WEDNESDAY THROUGH FRIDAY/...
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Quiet, comfortable weather for Wednesday as a ridge of surface high
pressure over the region slowly migrates towards then away from the
East Coast. A weak 500mb shortwave ripple could bring some passing
mid/high clouds during the day, though plenty of dry air in place in
the lower levels should preclude any shower development. High
temperatures will mostly range in the low/mid 70s, though with a few
upper 60s across the Tug Hill.

Dry weather continues through Wednesday night with mostly clear
skies. Warm air advection and a gentle southerly flow developing on
the backside of the high off the coast will result in a broader
range of low temperatures...With low 60s across far western NY and
upper 40s across the higher elevations in the North Country.

Conditions will begin to deteriorate later Thursday afternoon as the
flow aloft becomes nearly zonal out ahead of the next low pressure
system. This will be forced by a mid-level trough pivoting across
the Great Lakes from southern MB/ON provinces. Weak leading
shortwave energy is expected to ripple through the zonal flow over
the Northeast, which combined with growing diurnal instability will
lead to additional clouds and possibly a few showers or an isolated
tstorm, mainly over and in the vicinity of Lake Ontario where
synoptic moisture will be slightly deeper. Otherwise, a briefly
tightening pressure gradient over the region will lead to a breezier
day east/northeast of the lakes as afternoon temps across the area
top out in the low to mid 80s.

Broad surface low pressure ahead of the shortwave to the north will
lift northeast from eastern Ontario to central Quebec Thursday night
while deepening to near 990mb. The system`s trailing cold front will
sag southward through the eastern Great Lakes, leading to greater
chances for showers across the region overnight into Friday morning.
While the 00z suite of model guidance has come into better agreement
on a sharper parent shortwave and the arrival time of the initial
front, there remains greater forecast uncertainty in regards to
shower coverage and QPF overnight and on Friday as remnant moisture
from earlier convection moving east across the Ohio Valley
potentially interacts with the pre-frontal wave. At this juncture,
greatest chances for showers looks to be across the North Country
Thursday night in closer proximity to the surface low though
depending on how the aforementioned convection evolves, more
widespread showers could move through the Southern Tier overnight.
Outside of a spot shower or two, mainly dry weather should arrive
across the western zones by the afternoon. For temperatures, the
ushering in of the cooler overhead airmass should knock highs temps
back into the 70s Friday.
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&&

.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
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Any showers or thunderstorms associated with the earlier frontal
passage on Friday should be well south and east of the area by
Friday night as the axis of the parent upper-level trough will
quickly move east of the Great Lakes overnight. A large area of
surface high pressure and subsidence drying under a building ridge
aloft will expand east across the region through Saturday, then move
off to New England Sunday before settling off the coastline by
Monday. While there could be a few diurnal showers across the area
Monday afternoon, this pattern will otherwise support mainly dry
weather through the weekend.

While shower potential remains uncertain, confidence is much
higher in true summer`s heat building by early next week. Highs
on Saturday in the 70s will warm to the upper 80s and low 90s by
Monday as 850H temps are expected to reach or exceed +20C.
Though beyond the scope of the 7-day forecast...The strong
surface high is expected to remain off the coast through much of
the week which should continue to support warmer than normal
temperatures, as reflected well by CPC`s latest 6-10 and 8-14
temperature outlooks.
-- End Changed Discussion --

&&

.AVIATION /08Z TUESDAY THROUGH SATURDAY/...
A mid level low will continue to spin across New England today, with
cool cyclonic flow in its wake producing extensive stratus and
stratocumulus across the eastern Great Lakes. Widespread MVFR CIGS
will continue through the first half of today.

The system will finally begin to move off the east coast later this
afternoon and tonight, with the cloud deck gradually improving to
VFR and scattering out. VFR will prevail tonight in most areas,
although some patchy river valley fog will develop across the
Southern Tier with local IFR.

Outlook...

Wednesday through Thursday...VFR.

Thursday night and Friday...VFR/MVFR. Showers and thunderstorms
likely.

Friday night through Saturday...VFR.

&&

.MARINE...
Light winds will return today on Lake Erie and Lake Ontario, with
residual wave action gradually settling down after a number of windy
days as of late. Relatively light winds will continue through
Wednesday night.

A cold front will then move across the eastern Great Lakes late
Thursday night and early Friday. Southwest winds will increase ahead
of the front Thursday, with winds remaining elevated through Friday.
This will bring choppy conditions to both lakes.

&&

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

&&

$$

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