654
FXUS61 KBUF 081848
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
148 PM EST Fri Nov 8 2024

.SYNOPSIS...
A cold front will drop southward across the area through this
evening, resulting in clouds and a few showers east of Lake
Ontario. High pressure will then build across the region late
tonight, bringing a return to fair and dry weather for Saturday.
The next chance for rain will be late Sunday through Monday as
low pressure and its associated fronts slide across the Great
Lakes.

&&

.NEAR TERM /THROUGH SATURDAY/...
A cold front just to our north will drop southward across the
region through this evening. Early this afternoon, cloud cover
has developed in advance of the cold front, with radar showing
some light rain showers east of Lake Ontario. These showers will
linger through this evening a cooler air aloft will support lake
enhancement, and as the trough axis digs across northern New
England. Rainfall amounts will be light, generally less than a
tenth of an inch. Meanwhile, winds gusting to 35 mph this
afternoon will diminish through this evening, following the
passage of the front.

Later tonight, high pressure across the central Great Lakes will
expand eastward across our region. Temperatures behind the cold
front will drop into the upper 20s to lower 30s tonight. By
Saturday, this surface high will be across our region resulting
in fair weather and sunny skies. It will be on the cool side
with highs mainly in the mid to upper 40s.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY NIGHT/...
The large, closed off storm system that has been impacting the 4-
Corners region the past couple of days will be in the process of
deepening in the mid-levels as it slowly drifts across the central
Plains Saturday night. It will then reach the Upper Midwest by
Sunday morning, then cross the Great Lakes region and pass just
north of the forecast area through Monday morning. This will then
quickly be followed by a secondary mid-level shortwave sliding out
of Ontario and into Southern Quebec, which will then reach northern
New England by Tuesday morning. While the former has been bringing
portions of Colorado and New Mexico quite a lot of snow, for western
and north-central NY precipitation resulting from the system will
fall in the form of plain rain.

Looking a bit closer at the details...High pressure ridging at all
levels will shift east of the Great Lakes Saturday night and move
off the coast through the day Sunday while continue to provide dry
weather across the forecast area through much of Sunday morning.
Conditions will then quickly deteriorate from west to east with the
arrival of a southwesterly 45-50kt LLJ coupled with continued height
falls/DPVA aloft, resulting in a broad swath of rain that will work
into the region. While there could be a few showers out ahead, the
steadiest rains should arrive in southwestern NY by late Sunday
morning, then shift to the Genesee Valley by Sunday afternoon,
reaching the eastern Lake Ontario region by the evening. A period of
fairly steady rain is expected through at least the first half of
Sunday night as the system`s occluded front treks across the area.
Coverage and intensity should then taper off across western NY as
the system`s dry slot works in behind the front, though 850H temps
dipping to around +2 to +3C will support a limited lake response and
combined with upslope enhancement, rain showers are expected to
continue east/northeast of Lake Erie through the remainder of the
night and through Monday. Once the front clears the North Country by
early Monday morning, a similar setup of lake enhancement and
upsloping will allow showers to continue east of Lake Ontario as
well.

Rainfall Sunday through Sunday night will provide only limited
relief from the D0 (abnormally dry) antecedent conditions found
across from the area...With totals generally around a half inch in
the western Southern Tier and on the southern slopes of the Tug, to
around 0.15" up near the St. Lawrence, with totals of 0.25"-0.5"
elsewhere.

The aforementioned secondary shortwave trough will then send a cold
front through the region Monday night. The colder airmass and brief
uptick in synoptic moisture will likely reinvigorate the shower
activity east of the lakes early in the night, before the airmass
dries out again by Tuesday morning. 850H temps dipping to around -4C
or -5C in the wake of this front could potentially support a few wet
flakes across the higher terrain east of the lakes before daybreak.

&&

.LONG TERM /TUESDAY THROUGH THURSDAY/...
Tuesday, a mid level trough will dig across northern New England,
quickly followed by surface high pressure building into the Great
Lakes later in the day. A northwest flow of cooler air and some
limited wrap around moisture may still support a few lake effect
rain showers southeast of the lakes in the morning, with a drying
trend developing later in the day.

Tuesday night through Wednesday, strong high pressure will build
east across southern Quebec and into New England, providing a
stretch of dry weather through the middle of the week.

Later Wednesday night through the end of the week, a strong mid
level trough will advance out of the mid section of the nation,
reaching the Great Lakes and Ohio Valley Thursday, then diminishing
in amplitude by Friday as it moves into New England. This system
will capture a plume of Gulf of Mexico moisture on its way across
the central CONUS, spreading the likelihood of rain into the eastern
Great Lakes later Wednesday night and Thursday as mid level height
falls and a surface cold front move east across the area.

Model guidance begins to diverge on the details by next Friday, but
in general a secondary coastal system will likely remain too far
east to have a direct impact on our area. The passage of the
weakening mid level trough and cooler air aloft may support a few
more showers, and it may become just cold enough to allow for some
wet snow to mix in across higher terrain, but nothing significant is
expected.

&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
Clouds associated with a cold front dropping southward across
the region will expand across most TAF sites through this
evening. Cloud bases will mainly be 3-4k feet, resulting in MVFR
flight conditions at times, especially across higher terrain. A
few showers can`t be ruled out east of Lake Ontario.

After this, skies will clear out later tonight, giving way to
widespread VFR flight conditions for Saturday.

Outlook...

Saturday night...VFR.
Sunday...MVFR/IFR with showers.
Monday...MVFR with showers likely.
Tuesday...Mainly VFR.
Wednesday...VFR.

&&

.MARINE...
A cold front dropping southward across the area will result in
stronger westerly winds through this evening. Winds will
diminish as they shift to the north following the passage of the
cold front later tonight. This will support high end Small
Craft Advisory conditions on both lakes with sustained winds
approaching 30 knots.

High pressure will build across the lower Great Lakes late
tonight and Saturday, with light winds and negligible waves
developing.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...None.
MARINE...Small Craft Advisory until 7 PM EST this evening for LEZ020.
         Small Craft Advisory until 1 AM EST Saturday for LEZ040-
         041.
         Small Craft Advisory until 4 AM EST Saturday for
         LOZ042.
         Small Craft Advisory until 7 AM EST Saturday for
         LOZ043>045.

&&

$$

SYNOPSIS...Apffel/EAJ
NEAR TERM...Apffel
SHORT TERM...PP
LONG TERM...Hitchcock
AVIATION...Apffel
MARINE...Apffel